BS EN 61557-12-2008

BRITISH STANDARD

Electrical safety in low voltage distribution systems up to 1 000 V a.c. and 1 500 V d.c. — Equipment for testing, measuring or monitoring of protective measures — Part 12: Performance measuring and monitoring devices (PMD)

ICS 17.220.20; 29.080.01; 29.240.01

           

BS EN 61557-12:2008

BS EN 61557-12:2008

National foreword This British Standard is the UK implementation of EN 61557-12:2008. It is identical to IEC 61557-12:2007. The UK participation in its preparation was entrusted to Technical Committee PEL/85, Measuring equipment for electrical and electromagnetic quantities.  A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations.

This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 June 2008

© BSI 2008

ISISBN 978 0 580 56285 3

 Amendments/corrigenda issued since publication Date

Comments

EUROPEAN STANDARD

EN 61557-12

NORME EUROPÉENNE EUROPÄISCHE NORM

May 2008

ICS 17.220.20; 29.080.01; 29.240.01

English version

Electrical safety in low voltage distribution systems s ystems up to 1 000 V a.c. and 1 500 V d.c. Equipment for testing, measuring or monitoring of protective measures Part 12: Performance measuring and monitoring devices (PMD)

(IEC 61557-12:2007) Sécurité électrique dans les réseaux de distribution basse tension de 1 000 V c.a. et 1 500 V c.c. Dispositifs de contrôle, de mesure ou de surveillance de mesures de protection Partie 12: Dispositifs de mesure et de surveillance des performances (PMD) (CEI 61557-12:2007)

Elektrische Sicherheit in Niederspannungsnetzen Niederspannungsnetzen bis AC 1 000 V und DC 1 500 V Geräte zum Prüfen, Messen oder Überwachen von Schutzmaßnahmen Teil 12: Kombinierte Geräte zur Messung und Überwachung des Betriebsverhaltens (IEC 61557-12:2007)

This European Standard was approved by CENELEC on 2008-04-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.

CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels © 2008 CENELEC CENELEC -

All rights of exploitation exploitation in any any form and by any means means reserved worldwide for CENELEC members. Ref. No. EN 61557-12:2008 E

BS EN 61557-12:2008

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Foreword The text of document 85/311/FDIS, future edition 1 of IEC 61557-12, prepared by IEC TC 85, Measuring equipment for electrical and electromagnetic quantities, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61557-12 on 2008-04-01. This standard is to be used in conjunction with EN 61557-1:2007 (unless otherwise specified). The following dates were fixed:  – latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement

(dop)

 – latest date by which the national standards conflicting with the EN have to be withdrawn

(dow) 2011-04-01

2009-01-01

This European Standard has been prepared under a mandate given to CENELEC by the European Commission and the European Free Trade Association and covers essential requirements of EC Directive 2004/108/EC. See Annex ZZ.  Annexes ZA and ZZ have been added by CENELEC.  __________

Endorsement notice The text of the International Standard IEC 61557-12:2007 was approved by CENELEC as a European Standard without any modification.  __________

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BS EN 61557-12:2008

CONTENTS

INTRODUCTION..................................................................................................................... 7 1

Scope ............................................................................................................................... 8

2

Normative references ..................................................................................................... ..9

3

Terms and definitions ..................................................................................................... 10

4

3.1

General definitions ................................................................................................ 10

3.2

Definitions related to uncertainty and performance ................................................ 11

3.3

Definitions related to electric phenomena .............................................................. 14

3.4

Definitions related to measurement techniques ..................................................... 17

3.5

Notations............................................................................................................... 17 3.5.1

Functions .................................................................................................. 17

3.5.2

Symbols and abbreviations ........................................................................ 18

3.5.3

Indices ...................................................................................................... 18

Requirements ................................................................................................................. 18 4.1

General requirements ............................................................................................ 18

4.2

PMD general architecture ...................................................................................... 19

4.3

Classification of PMD ............................................................................................ 19

4.4

List of applicable performance classes .................................................................. 20

4.5

4.4.1

List of applicable function performance classes for PMD without external sensors ........................................................................................ 2 0

4.4.2

List of applicable system performance classes for PMD with external sensors ........................................................................................ 2 1

Operating and reference conditions for P MD ......................................................... 21 4.5.1

Reference conditions ................................................................................. 21

4.5.2

Rated o perating conditions ........................................................................ 21

4.6

Start-up conditions ................................................................................................ 23

4.7

Requirements for PMD functions (except PMD-A) .................................................. 23 4.7.1 4.7.2

 Act ive power (P ) and active energy ( E a ) measurements ............................ 23 Reactive power (Q A, Q V) and reactive energy ( E rA , E rV ) measurements ....28

4.7.3

 Apparent power (S A , S V ) and apparent energy (E ap A , E apV ) measurements ...........................................................................................3 1

4.7.4

Frequency (f ) measurements ..................................................................... 33

4.7.5 4.7.6

R.m.s. phase current (I ) and neutral current ( I N , I Nc ) measurements.......... 34 R.m.s. voltage (U ) measurements.............................................................. 39

4.7.7

Power factor (PF  A , PF V) measurements .................................................... 39

4.7.8

Short term flicker (P st ) and long term flicker (P lt ) measurements............... 39 Voltage dip (U dip ) and voltage swell ( U swl ) measurements ....................... 40

4.7.9

4.7.10 Transients overvoltage (U tr ) measurements .............................................. 42 4.7.11 Voltage interruption (U int ) measurements .................................................. 42 4.7.12 Voltage unbalance (U nb , U nba ) measurements ......................................... 43 4.7.13 Voltage harmonics (U h) and voltage THD (THD u  and THD-R u ) measurements ...........................................................................................4 4

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4.7.14 Current harmonics (I h) and current THD (THD i  and THD-R i ) measurements ........................................................................................... 45 4.7.15 Minimum, maximum, peak, three-phases average and demand measurements ........................................................................................... 46 4.8

Requirements for PMD-A functions ........................................................................ 46

4.9

General mechanical requirements ......................................................................... 47 4.9.1

Vibration requirem ents .............................................................................. 47

4.9.2

IP requirements ......................................................................................... 47

4.10 Safety requirements .............................................................................................. 48 4.10.1 Clearances and creepage distances .......................................................... 48 4.10.2 Connection of a fixed installed PMD with a current transformer ................. 48 4.10.3 Connection of a PMD with a high voltage sensor ....................................... 48 4.10.4  Acc essible parts ... ........ ... ... ........ ... ... ... ........ ... ... ........ ... ... ........ ... ... ... ........ . 48 4.10.5 Hazardous live parts .................................................................................. 49 4.11  Analog outputs ..... ... ... ........ ... ... ... ... ... ........ ... ... ... ... ... ........ ... ... ... ... ... ........ ... ... ... ... .. 49 4.11.1 General requirements ................................................................................ 49 4.11.2 Compliance voltage ................................................................................... 49 4.11.3  Analog output ripple content ... ... ... ... ... ... ... ... ... ........ ... ... ........ ... ... ... ........ ... . 49 4.11.4  Analog output response tim e ..... ... ... ........ ... ... ... ........ ... ... ........ ... ... ........ ... .. 49 4.11.5 Limiting value of the an alog output signal .................................................. 49 4.11.6 Pulse outputs ............................................................................................ 50 5

6

Marking and operating instructions ................................................................................. 50 5.1

Marking ................................................................................................................. 50

5.2

Operating a nd installation instructions ................................................................... 50 5.2.1

General characteristics .............................................................................. 50

5.2.2

Essential characteristics ............................................................................ 51

5.2.3

Safety characteristics ................................................................................ 53

Tests .............................................................................................................................. 53 6.1

Type tests of PMD ................................................................................................. 53 6.1.1

Test of temperature influence .................................................................... 54

6.1.2

 Act ive power ... ... ... ........ ... ... ........ ... ... ........ ... ... ........ ... ... ... ........ ... ... ........ ... . 54

6.1.3

 Apparent power ... ........ ... ... ... ... ... ........ ... ... ... ... ... ........ ... ... ... ... ... ........ ... ... ... 57

6.1.4

Power factor .............................................................................................. 57

6.1.5

Common mode voltage rejection test ......................................................... 57

6.1.6

Frequency ................................................................................................. 58

6.1.7

Measurement of voltage harmonics ........................................................... 58

6.1.8

Measurement of curr ent harmonics ............................................................ 58

6.1.9

Dips an d s wells ......................................................................................... 59

6.1.10 Voltage interr uptions ................................................................................. 59 6.1.11 Outputs tests ............................................................................................. 59 6.1.12 Climatic tests............................................................................................. 60 6.1.13 EMC tests.................................................................................................. 61 6.1.14 Start up tests ............................................................................................. 61 6.2

Type tests of P MD-A ............................................................................................. 61

6.3

Routine tests ......................................................................................................... 61 6.3.1

Protective bonding test .............................................................................. 61

6.3.2

Dielectric strength test ............................................................................... 62

6.3.3

Uncertainty test ......................................................................................... 62

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BS EN 61557-12:2008

 Annex A (informative) Definitions of electrical parameter s ... ... ... ... ... ... ..... ... ... ..... ... ..... ... ..... . 63  Annex B (norm ative) Def ini tions of minim um, maxim um, p eak and demand values ..... ... ... ... 67  Annex C (inform ative) Intri nsic unc ertaint y, operating uncertainty, and overall system uncertainty............................................................................................................................ 69  Annex D (informative) Recomm end ed sensor classes for the dif ferent kinds of PMD.... ... ... .. 7 1  Annex E (normative) Requirements applicable to PMD and to PMD-A ... ... ... ... ..... ... ..... ..... ... . 7 4  Annex ZA (normative) Normative references to international publications with their  corresponding European publications.................................................. ..................................77  Annex ZZ (inf o rmative) Coverage of Essential Requirements of EC Directives......................79

Bibliography..........................................................................................................................75 Figure 1 – PMD generic m easurement chain ......................................................................... 19 Figure 2 – Description of different types of PMD ................................................................... 2 0 Figure 3 – Relationship between ambient air temperature and relative humidity.................... 2 3 Figure 4 – Waveform for odd harmonics influence test on active power measurement .......... 5 4 Figure 5 – Spectral content for odd harmonics influence test on active power measurement. 5 5 Figure 6 – Waveform for sub-harmonics influence test on active power measurement .......... 5 6 Figure 7 – Spectral content for sub-harmonics influence test on active power measurement. 5 6 Figure 8 – Common m ode voltage influence testing ..............................................................5 7 Figure 9 – Waveform for harmonics influence test on frequency measurement...................... 58 Figure A.1 – Arithmetic and vector apparent powers in sinusoidal situation........................... 65 Figure A.2 – Geometric representation of active and reactive power .....................................6 6 Figure B.1 – Thermal current demand ................................................................................... 6 7 Figure C.1 – Different kind of uncertainties ........................................................................... 69 Table 1 – Classification of P MD ............................................................................................ 2 0 Table 2 – List of applicable function performance classes for PMD without external sensors 20 Table 3 – List of applicable system performance classes for PMD with external sensors....... 21 Table 4 – Reference conditions for testing ............................................................................ 2 1 Table 5 – Rated operating temperatures for portable equipment ...........................................2 2 Table 6 – Rated operating temperatures for fixed installed equipment .................................. 2 2 Table 7 – Humidity and altitude operating conditions ............................................................ 2 2 Table 8 – Intrinsic uncertainty table for active power and active energy measurement .......... 2 4 Table 9 – Influence quantities for active power and active energy measurement................... 25 Table 10 – Starting current for active power and active energy measurement ....................... 28 Table 11 – Intrinsic uncertainty table for reactive power and reactive energy measurement . 2 8 Table 12 – Influence quantities for reactive power and reactive energy measurement...........

29

Table 13 – Starting current for reactive energy measurement ...............................................3 1 Table 14 – Intrinsic uncertainty table for apparent power and apparent energy measurement ............................................................................................................31 Table 15 – Influence quantities for apparent power and apparent energy measurement........ 3 2 Table 16 – Intrinsic uncertainty table for frequency measurem ent ......................................... 3 3

BS EN 61557-12:2008

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Table 17 – Influence quantities for frequency mea surement ................................ ................................................ .................. .. 33 Table 18 – Rated range of operation for phase current measurement .............................. ................................... ..... 34 Table 19 – Rated range of operation for neutr al current measurement ............................. .................................. ..... 34 Table 20 – Intrinsic uncertainty table for phase current ................................. ................................................. ........................ ........ 35 Table 21 – Intrinsic u ncertainty table for neutral c urrent measurement ................................ .................................. .. 35 Table 22 – Intrinsic uncertainty table for neutral curre nt calculation ............................... ...................................... ....... 35 Table 23 – Influence quantities for phase current and neutral current measurement ............. 36 Table 24 – Rated r ange of operation for r .m.s. voltage measurem ent................................... ent..................................... 37 Table 25 – Intrinsic uncertainty table for r.m.s. voltage measurement ............................... ................................... .... 37 Table 26 – Influence quantities for r.m.s. voltage m easurement .............................. ............................................ .............. 38 Table 27 – Intrinsic uncertainty table for power factor measurem ent .............................. ..................................... ....... 39 Table 28 – Intrinsic uncertainty table for flicker measurem ent ............................... ............................................... ................ 39 Table 29 – Rated range of operation for voltage dips and swells measurement..................... 40 Table 30 – Intrinsic uncertainty table for voltage dips and swells measurement .................... .................... 40 Table 31 – Influence quantities for dips and swells swells measurement ............................... ......................................... .......... 41 Table 32 – Intrinsic uncertainty table for transient overvoltage measurement........................ 42 Table 33 – Intrinsic uncertainty table for voltage interruption interruption measurement .......................... .......................... 43 Table 34 – Intrinsic uncertainty table for voltage unbalance measurement ............................ ............................ 43 Table 35 – Rated range of operation for voltage harmonics measurement ............................ ............................ 44 Table 36 – Intrinsic uncertainty table for voltage harmonics measurement ............................ ............................ 44 Table 37 – Intrinsic uncertainty table for voltage THD TH D u  or  o r THD-R u measurement measurement ......... .............. ........ ... 44 Table 38 – Rated range of operation for current harmonics measurement............................. 45 Table 39 – Intrinsic Intrinsic uncertainty table for current harmonics measurement ............................ ............................ 45 Table 40 – Intrinsic uncertainty table for current THD TH D i and THD-R i  measurement measurement ......... .............. ........ ... 46 Table 41 – Complementary characteristics of PMD-A ................................. ................................................. ........................... ........... 47 Table 42 – Minimum IP requirements for PMD ................................. .................................................. ................................. .................... .... 48 Table 43 – PMD s pecification form........................................ form......................................................... ................................. ............................... ............... 51 Table 44 – Characterist ics specification template.................................... template..................................................... .............................. ............. 52 Table 45 – Characteristics specification template ............................... ............................................... ................................ ................... ... 5 3 Table A.1 – Symbols definition........................... definition........................................... ................................. ................................. ................................. ................... 63 Table A.2 – Calculation definitions of electrical parameters, for 3 phase unbalanced system with neutral ................................. .................................................. .................................. ................................... ................................... ..........................6 .........6 4 Table D.1 – PMD SD associated to current sensor or PMD DS associated to voltage sensor ................................ ................................................. ................................... ................................... .................................. .................................. .............................7 ............7 1 Table D.2 – PMD SS with Current Sensor an d Voltage Sensor association ........................... ........................... 72 Table D.3 – Range of applicable performance classes for PMD without its associated external sensors ................................. .................................................. .................................. .................................. .................................. ............................... .............. 73 Table D.4 – Range of applicable performance classes when calculating performance class of PMD with its associated external sensors ................................ ................................................. .................................. ............................7 ...........7 3 Table D.5 – List of functions affected by uncertainty of external sensors...............................7 3 Table E.1 – Requirem ents applicable to PMD an d to PMD-A............................................. PMD-A................................................. .... 74

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BS EN 61557-12:2008

INTRODUCTION  As a comp co mp leme le ment nt to pr otec ot ecti tion on me asu res , it bec om es mo re and an d mo re nec essar es sar y to me asur as ur e different electrical parameters, in order to monitor the required performances in energy distribution systems due to:

•

installation standards evolutions, for instance over over current detection is now a new requirement for the neutral conductor due to harmonic content;

•

technological evolutions (electronic loads, electronic measuring methods, etc.);

• • •

end-users needs (cost saving, compliance with aspects of of building regulations, etc..); safety and continuity of service; sustainable development requirements where where energy measurement for instance is recognised as an essential element of energy management, part of the overall drive to reduce carbon emissions and to improve the commercial efficiency of manufacturing, com mer cial organisation organisations s and public services services.

The devices on the current market have different characteristics, which need a common system of references. Therefore there is a need for a new standard in order to facilitate the choices of the end-users in terms of performance, safety, interpretation of the indications, etc. This standard provides a basis by which such devices can be specified and described, and the ir performance performance evaluated. evaluated.

BS EN 61557-12:2008

 – 8 – 

ELECTRICAL SAFETY IN LOW VOLTAGE DISTRIBUTION SYSTEMS UP TO 1 000 V a.c. AND 1 500 V d.c. – EQUIPMENT FOR TESTING, MEASURING OR MONITORING OF PROTECTIVE MEASURES – Part 12: Performance measuring and monitoring devices (PMD)

1

Scope

This part of IEC 61557 specifies requ irements for combined performance measuring and monitoring devices that measure and monitor the electrical parameters within electrical distribution systems. These requirements also define the performance, in single and threephase a.c. or d.c. systems having rated voltages up to 1 000 V a.c. or up to 1 500 V d.c. These devices are fixed installed or portable. They are intended to be used indoors and/or outdoors. This standard is not applicable for:

•

electricity metering equipment t hat complies with IEC 62053-21, IEC 62053-22 and IEC 62053-23. Nevertheless, uncertainties defined in this standard for active and reactive energy measurement are derived from those defined in the IEC 62053 standards series.

•

simple remote relays or simple monitoring relays.

This standard is intended to be used in conjunction with IEC 61557-1 (unless otherwise specified), which specifies the general requirements for measuring and monitoring equipment, as required in IEC 60364-6. The standard does not include the measurement and monitoring of electrical parameters defined in Parts 2 to 9 of IEC 61557 or in IEC 62020. Combined performance measuring and monitoring devices (PMD), as defined in this standard, give additional safety information, which aids the verification of the installation and enhances the performance of the distribution systems. For instance, those devices help to check if the level of harmonics is still compliant with the wiring systems as required in IEC 60364-5-52. The Th e combined performance measuring and monitoring devices (PMD) for electrical parameters described in this standard are used for general industrial and commercial applications. A PMD-A is a specific PMD complying with r equirements of IEC 61000-4-30 class A, which may be used in "power quality assessment" applications. NOTE 1

Generally such types types of devices are used in the following following applications or for the following following general needs:

 –

ene rgy ma nag em ent ins ide th e ins tal lat io n;

 –

mo nit ori ng an d/o r m eas ure me nt of ele ct ric al par am et ers th at ma y b e req ui red or usu al;

 –

me asu rem ent and /o r m oni to rin g of th e q ual it y o f ene rgy .

NOTE 2 A measuring and monitoring device of electrical parameters usually consists of several functional modules. All or some of the functional modules are combined in one device. Examples of functional modules are mentioned below:  –

me asu rem ent and in dic at ion of sev era l ele ctr ica l par am ete rs sim ult ane ous ly;

 – 9 – 

BS EN 61557-12:2008

 –

ene rgy me asu rem ent an d/o r m oni to rin g, an d a lso som et ime s c om pli anc e wit h asp ect s of bui ld ing reg ul ati ons ;

 –

ala rms fun ct ion s;

 –

pow er qua lit y (ha rmo nic s, ove r/u nde rvo lt age s, vol ta ge di ps and swe ll s, et c).

2

Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60068-2-1, Environmental testing – Part 2-1: Tests – Test A: Cold IEC 60068-2-2, Environmental testing – Part 2: Tests – Tests B: Dry heat IEC 60068-2-30, Environmental testing – Part 2-30 – Tests –Test Db: Damp heat, cyclic (12 h + 12 h cycle) IEC 60364-6, Low-voltage electrical installations – Part 6: Verification IEC 60529, Degrees of protection provided by enclosures (IP Code) IEC 61000-4-5, Electromagnetic compatibility (EMC) – Part 4-5: Testing and measurement techniques – Surge immunity test IEC 61000-4-15, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement techniques – Section 15: Flickermeter – Functional and design specifications IEC 61000-4-30:2003, Electromagnetic compatibility (EMC) – measurement techniques – Power quality measurement methods

Part

4-30:

Testing

and

IEC 61010 (all parts), Safety requirements for electrical equipment for measurement, control, and laboratory use IEC 61010-1:2001, Safety requirements for electrical equipment for measurement, control, and laboratory use – Part 1: General requirements IEC 61326-1:2005, Electrical equipment for measurement, control and laboratory use – EMC requirements – Part 1: General requirements IEC 61557-1:2007, Electrical safety in low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. – Equipment for testing, measuring or monitoring of protective measures – Part 1: General requirements IEC 62053-21:2003, Electricity metering equipment (a.c.) – Particular requirements – Part 21: Static meters for active energy (classes 1 and 2) IEC 62053-22:2003, Electricity metering equipment (a.c.) – Particular Requirements – Part 22: Static meters for active energy (classes 0,2 S and 0,5 S) IEC 62053-23:2003, Electricity metering equipment (a.c.) – Particular requirements – Part 23: Static meters for reactive energy (classes 2 and 3) IEC 62053-31:1998, Electricity metering equipment (a.c.) – Particular requirements – Part 31: Pulse output devices for electromechanical and electronic meters (two wires only)

BS EN 61557-12:2008

3

 – 10 – 

Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 61557-1, unless otherwise specified in this standard, and the following terms and definitions apply. 3.1

General definitions

3.1.1 performance measuring and monitoring device PMD combination in one or more devices of several functional modules dedicated to measuring and monitoring electrical parameters in energy distribution systems or electrical installations. A PMD can be used in connection with sensors (see 4.3 )  A PMD that complies wit h class B as defined in IEC 61000-4-30 is als o cover ed by this definition. NOTE 1

Under the generic term “monitoring” are also included functions of recording, alarm management etc.

NOTE 2

These devices may include power quality functions.

3.1.2 PMD-A PMD in which all power quality assessment functions comply with measurement methods and performance requirements according to class A of IEC 61000-4-30 and with complementary requirements (safety, EMC, temperature range, complementary influence quantities, …) of this standard NOTE If this device is used for checking the compliance to the connection agreement with a network operator, it should be installed at the interface point between the installation and the network.

3.1.3 power quality assessment functions power quality functions whose measurement methods are defined in IEC 61000-4-30 3.1.4 specified external sensor sensor that is chosen in such a way that, connected to a PMD without sensors, the system performance class complies with 4.4.2 3.1.5 current sensor CS electrical, magnetic, optical or other device intended to transmit a signal corresponding to the current flowing through the primary circuit of this device NOTE  A c urr ent tra nsf orm er (CT) is in gen era l a ma gne tic cu rre nt se nso r.

3.1.6 compliance voltage value of the voltage that can be developed at the output of a current generator while conforming to the requirement of the uncertainty specification for that output NOTE

This definition applies to current analogue output signals.

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BS EN 61557-12:2008

3.1.7 voltage sensor VS electrical, magnetic, optical or other device intended to transmit a signal corresponding to the voltage across the primary terminals of this device NOTE

A voltage transformer (VT) is in general a magnetic voltage sensor.

3.1.8 self-powered PMD equipment able to work without an auxiliary power supply NOTE 1

Self powered PMD have no provision for power supply terminals.

NOTE 2 Self powered PMD includes equipment powered from measurement inputs, internal batteries, or other internal power sources (internal photo-voltaic sources, etc.).

3.1.9 auxiliary power supply external power supply, either a.c. or d.c. that powers the PMD through dedicated terminals separated from the measurement inputs of the PMD 3.2

Definitions related to uncertainty and performance

3.2.1 reference conditions appropriate set of specified values and/or ranges of values of influence quantities under which the smallest permissible uncertainties of a measuring instrument are specified NOTE The ranges specified for the reference conditions, called reference ranges, are not wider, and are usually narrower, than the ranges specified for the rated operating conditions.

[IEC 60359, definition 3.3.10] 3.2.2 intrinsic uncertainty uncertainty of a measuring instrument when used under reference conditions. In this standard, it is a percentage of the measured value defined in its rated range and with the other influence quantities under reference conditions, unless otherwise stated [IEC 60359, definition 3.2.10, modified] 3.2.3 influence quantity quantity which is not the subject of the measurement and whose change affects the relationship between the indication and the result of the measurement NOTE 1 Influence quantities can o riginate from the measured system, the measuring equipment or the environment [IEV]. NOTE 2 As the calibration diagram depends on the influence quant ities, in order to assign the result of a measurement it is necessary to know whether the relevant influence quantities lie within the specified range [IEV].

[IEC 60359, definition 3.1.14 modified] 3.2.4 variation (due to a single influence quantity) difference between the value measured under reference conditions and any value measured within the influence range NOTE The other performance characteristics and the other influence quantities should stay within the ranges specified for the reference conditions.

BS EN 61557-12:2008

 – 12 – 

3.2.5 (rated) operating conditions set of conditions that must be fulfilled during the measurement in order that a calibration diagram may be valid NOTE Beside the specified measuring range and rated operating ranges for the influence quantities, the conditions may include specified ranges for other performance characteristics and ot her indications that cannot be expressed as ranges of quantities.

[IEC 60359, definition 3.3.13] 3.2.6 operating uncertainty uncertainty under the rated operating conditions NOTE The operating instrumental uncertainty, like the intrinsic one, is not evaluated by the user of the instrument, but is stated by its manufacturer or calibrator. The statement may be expressed by means of an algebraic relation involving the intrinsic instrumental uncertainty and the values of one or several influence quantities, but such a relation is just a convenient means of expressing a set of operating instrumental uncertainties under different operating conditions, not a functional relation to be used for evaluating the propagation of uncertainty inside the instrument.

[IEC 60359, definition 3.2.11, modified] 3.2.7 overall system uncertainty uncertainty including the instrumental uncertainty of several separated instruments (sensors, wires, measuring instrument, etc.) under the rated operating conditions 3.2.8 function performance class performance of a single function without external sensors, expressed as a percentage and depending on function intrinsic uncertainty and on variations due to influence quantities NOTE

In this standard, C  stands for function performance class.

3.2.9 system performance class performance of a single function including specified external sensors expressed as a percentage and depending on function intrinsic uncertainty and on variations due to influence quantities NOTE

In this standard, C  stands also for system performance class.

3.2.10 rated frequency f n

value of the frequency in accordance with which the relevant performance of the PMD is fixed NOTE

f n stands for nominal frequency in IEC 61557-1.

3.2.11 rated current I n

value of current in accordance with which the relevant performance of an PMD operated by an external current sensor (PMD Sx) is fixed [IEV 314-07-02, modified] NOTE

I n stands for nominal c urrent in IEC 61557-1.

 – 13 – 

BS EN 61557-12:2008

3.2.12 basic current I b

value of current in accordance with which the relevant performance of a direct connected PMD (PMD Dx) is fixed [IEC 62052-11, definition 3.5.1.2, modified] 3.2.13 starting current I st

lowest value of the current at which the PMD starts and continues to register [IEC 62052-11, definition 3.5.1.1, modified] 3.2.14 maximum current I max

highest value of current at which the PMD meets the uncertainty requirements of this standard [IEC 62052-11, definition 3.5.2, modified] 3.2.15 rated voltage U n

value of the voltage in accordance with which the relevant performances of the PMD are fixed. Depending on the distribution system and its connection to the PMD, this voltage can be either the phase to phase voltage or the phase to neutral voltage NOTE

U n stands for nominal voltage in IEC 61557-1.

3.2.16 nominal voltage U nom

a suitable approximate value of voltage used to designate or identify a system [IEV 601-01-21] 3.2.17 minimum voltage U min

lowest value of voltage at which the PMD meets the uncertainty requirements of this standard

3.2.18 maximum voltage U max

highest value of voltage at which the PMD meets the uncertainty requirements of this standard 3.2.19 declared input voltage U din

value obtained from the declared supply voltage by a transducer ratio [IEC 61000-4-30, definition 3.2]

BS EN 61557-12:2008

 – 14 – 

3.2.20 residual voltage U resid

minimum value of U recorded during a voltage dip or interruption NOTE The residual voltage is expressed as a value in volts, or as a percentage or per unit value of the rated voltage.

[IEC 61000-4-30, definition 3.25, modified] 3.2.21 demand value average value of a quantity over a specified period of time 3.2.22 peak demand value highest demand value (positive or negative) since the beginning of the measurement or the last reset 3.2.23 thermal demand emulation of a thermal demand meter that provides an exponentially time lagged demand, given a constant load, the indication reading 90% of the actual demand in a specified time NOTE

Time is specified by manufacturer, usually 15 min.

3.2.24 three-phase average value in a three- or four-wire system, the arithmetical average of each phase value 3.2.25 maximum value highest value measured or calculated since the beginning of the measurement or the last reset 3.2.26 minimum value lowest value measured or calculated since the beginning of the measurement or last reset 3.2.27 interval period of time used by the PMD to integrate r.m.s. or instantaneous values in order to calculate demand values 3.3

Definitions related to electric phenomena

3.3.1 phase current I

value of the current flowing in each phase of an electrical distribution system 3.3.2 neutral current I N

value of neutral current of an electrical distribution system

 – 15 – 

BS EN 61557-12:2008

3.3.3 phase to phase voltage line to line voltage U

the voltage between phases [IEV 601-01-29] 3.3.4 phase to neutral voltage line to neutral voltage V

voltage between a phase in a polyphase system and the neutral point [IEV 601-01-30] 3.3.5 frequency f

value of measured frequencies in an electrical distribution system 3.3.6 power factor PF

under periodic conditions, ratio of the absolute value of the active power  to the apparent power NOTE

This power factor is not the displacement power factor.

[IEV 131-11-46, modified] 3.3.7 amplitude of harmonic current I h

value of the amplitude of the current at harmonic frequencies in the spectrum obtained from a Fourier transform of a time function 3.3.8 amplitude of harmonic voltage U h

value of the amplitude of the voltage at harmonic frequencies in the spectrum obtained from a Fourier transform of a time function 3.3.9 stationary harmonics (voltage and current) harmonic content of the signal with the amplitude variation of each harmonic component remaining constant within ± 0,1 % of the amplitude of the fundamental 3.3.10 quasi-stationary harmonics (voltage and current) harmonic content of the signal with the amplitude variation of each harmonic component of each contiguous 10/12 cycles window remaining within ± 0,1 % of the fundamental 3.3.11 sub-harmonics (voltage and current) interharmonic component of harmonic order lower than one NOTE

In this standard sub-harmonic components are restricted to ranks being reciprocal of integers.

[IEV 551-20-10, modified]

BS EN 61557-12:2008

 – 16 – 

3.3.12 flicker impression of unsteadiness of visual sensation induced by a light stimulus whose luminance or spectral distribution fluctuates with time [IEV 161-08-13] 3.3.13 voltage dip temporary reduction of the voltage at a point in the electrical distribution system below a defined threshold NOTE 1 Interruptions are a special case of a voltage dip. Post-processing may be used to distinguish between voltage dips and interruptions. NOTE 2 In some areas of the world a voltage dip is referred to as sag. The two terms are considered interchangeable; however, this standard will only use the term voltage dip.

[IEC 61000-4-30, definition 3.30, modified] 3.3.14 voltage swell temporary increase of the voltage at a point in the electrical distribution system above a defined threshold [IEC 61000-4-30, definition 3.31, modified] 3.3.15 voltage interruption reduction of the voltage at a point in the electrical distribution system below a defined interruption threshold 3.3.16 amplitude and phase unbalanced voltage condition in a three-phase system in which the r.m.s. values of the line voltages (fundamental component), or the phase angles between consecutive line voltages, are not all equal NOTE 1 The degree of the inequality is usually expressed as the ratios of the negative-sequence and zerosequence components to the positive-sequence component. NOTE 2

In this standard, voltage unbalance is considered in relation to three-phase systems.

[IEV 161-08-09, modified] 3.3.17 amplitude unbalanced voltage condition in a three-phase system in which the r.m.s. values of the line voltages (fundamental component) are not all equal. Relative phase between the line voltages is not taken into account. NOTE

In this standard, voltage unbalance is considered in relation to three-phase systems.

[IEV 161-08-09, modified] 3.3.18 transient overvoltage short-duration overvoltage of few milliseconds or less, oscillatory or non-oscillatory, usually highly damped. [IEV 604-03-13] NOTE 1 Transient overvoltages may be immediately followed by temporary overvoltages. In such cases the two overvoltages are considered as separate events.

 – 17 – 

BS EN 61557-12:2008

NOTE 2 IEC 60071-1 defines three types of transient overvoltages, namely slow-front overvoltages, fast-front overvoltages and very fast-front overvoltages according to their time to peak, tail or total duration, and possible superimposed oscillations.

3.3.19 mains signalling voltage signals transmitted by energy suppliers on public networks for network management purposes, such as the control of some categories of load. NOTE Technically, mains signalling is a source of interharmonics voltages. In this case, however, the signal voltage is intentionally impressed on a selected part of the supply system. The voltage and frequency of the emitted signal are pre-determined, and the signal is transmitted at particular times.

3.4

Definitions related to measurement techniques

3.4.1 zero blind measurement measurement technique where the measurement is performed continuously. For digital techniques and for a given sampling rate, no sample shall be missing in the measurement processing. NOTE When zero blind measurement techniques are used, no assumption is made regarding the stability of the signal, in opposition with non-zero blind measurement techniques, where the signal is considered to be stable during the time where no measurement is done.

3.5

Notations

3.5.1 Functions Symbol

Function

P

total active power

E a

total active energy

Q A / Q V

total reactive power arithmetic / total reactive power vector

E rA  / E rV

total reactive energy arithmetic / total reactive energy vector

S A / S V

total apparent power arithmetic / total apparent power vector

E apA  / E apV

total apparent energy arithmetic / total apparent energy vector

f 

frequency

I 

phase current including I p (current on Line p)

I N  / I Nc

measured neutral current / calculated neutral current

U 

voltage including U pg  (line p to line g voltage) and V p  (line p to neutral voltage)

U din

declared input voltage [IEC 61000-4-30]

PF A / PF V

power factor arithmetic / power factor vector NOTE PF V  = cos(ϕ ) when no harmonics are present

P st  / P lt

short term flicker / long term flicker

U dip

voltage dips including U pg dip  (line p to line g) and V p dip  (line p to neutral)

U swl

voltage swells including U pg swl  (line p to line g) and V p swl  (line p to neutral)

U tr 

transients overvoltage including U pg tr  (line p to line g) and V p t r  (line p to neutral)

U int

voltage Interruption including U pg int  (line p to line g) and V p int  (line p to neutral)

U nb

voltage Unbalance phase and amplitude including V p nb  (line p to neutral)

U nba

voltage Unbalance amplitude including V p nba  (line p to neutral)

U h

voltage harmonics including U pg h (line p to line g) and V p h (line p to n eutral)

THD u

total harmonic distortion voltage related t o fundamental

THD-R u

total harmonic distortion voltage related to r.m.s. value

BS EN 61557-12:2008

 – 18 – 

I h

current harmonics including I p h (harmonics on line p)

THD i

total harmonic current related to fundamental

THD-R i

total harmonic current related to r.m.s. value

Msv 

mains signalling voltage

3.5.2 Symbols and abbreviations %U n

percentage of U n

%I n

percentage of I n

%I b

percentage of I b

3.5.3 Indices

4 4.1

a

active

r

reactive

ap

apparent

n

rated

b

basic

nom

nominal

N

neutral

c

calculated

h

harmonic

i

current

u

voltage

dip

dips

swl

swells

tr

transient

int

interruption

nb

unbalance

nba

amplitude unbalance

A

arithmetic

V

vectorial

min

minimum value

max

maximum value

avg

average value

peak

peak value

resid

residual

Requirements General requirements

The following r equirements as well as those given in I EC 61557-1 shall apply unless otherwise specified hereafter. For safety requirements, IEC 61010-1, applicable requirements specified hereafter shall apply.

parts

of IEC 61010 and

additional

 – 19 – 

BS EN 61557-12:2008

For electromagnetic compatibility (E MC) requirements, IEC 61326-1 shall apply unless otherwise specified hereafter. F or imm unity, Table 2 of IEC 61326-1 ( Immunity test requirements for equipment intended for use in industrial locations) shall apply. For emission either class A or class B limits as defined in IEC 61326-1 shall apply. NOTE

Guidance for requirements applicable to PMD-A or/and PMD is given in  Ann ex E.

4.2

PMD general architecture

Organisation of the measurement chain: the electrical quantity to be measured may be either directly accessible, as it is generally the case in low-voltage systems, or accessible via measurement sensors like voltage sensors (VS) or current sensors (CS). Figure 1 below shows the common organisation of a PMD. In some cases when a PMD does not include the sensors, their associated uncertainties are not considered. When a PMD includes the sensors, their associated uncertainties are considered.

Communication protocol

Performance measuring and monitoring devices (PMD)

Measurement sensors (see Note)

 Acquisition unit

Communication management

Processing unit

Evaluation unit

Display unit

Digital I/O management

Electrical input signals

Input signal to be measured

Measurement results

Digital I/O IEC

1272/07

Figure 1 – PMD generic measurement chain NOTE

It is not necessary that the parts in the dotted lines shown in Figure 1 be included in the PMD.

4.3

Classification of PMD

PMD either can have an internal sensor, or may need an external sensor, as shown in Figure 2. Depending on these characteristics, PMD can be split in 4 categories as defined in Table 1.

BS EN 61557-12:2008

 – 20 – 

Table 1 – Classification of PMD Current measurement Sensor operated PMD (current sensors out of PMD)

Direct connected PMD (current sensors in PMD)

PMD Sx Direct connected PMD

   t (voltage sensors in PMD)   n   e   e   m   g  e PMD xD   a   r    t    l   u   o  s Sensor operated PMD    V  a   e (voltage sensors out of PMD)   m

PMD Dx

PMD SD

PMD DD

(Semi-direct insertion)

(Direct insertion)

PMD SS

PMD DS

(Indirect insertion)

(Semi-direct insertion)

PMD xS

U

U 

PMD SD

PMD DD

 Acquisition and processing units

 Acquisition and processing units

I  Current sensor 

I 

U 

U 

Voltage sensor 

PMD SS

Voltage sensor 

PMD DS

 Acquisition and processing units

 Acquisition and processing units

I 

I 

Current sensor 

IEC

1273/07

NOTE  A PMD spe cif ied as a PMD Dx (re spe ct ive ly PMD xD) can som eti me s und er cer tai n con dit ion s be use d as a PMD Sx (respectively PMD xS) when used with external sensors provided that it complies with both requirements of PMD Sx and Dx (respectively PMD xS and xD).

Figure 2 – Description of different types of PMD 4.4

List of applicable performance classes

4.4.1 List of applicable function performance classes for PMD without external sensors Table 2 specifies the list of allowed performance classes for a PMD without external sensors: Table 2 – List of applicable function performance classes for PMD without external sensors 0,02

0,05

0,1

0,2

0,5

1

1,5

2

2,5

3

5

10

20

BS EN 61557-12:2008

 – 21 – 

4.4.2 List of applicable system performance classes for PMD with external sensors Table 3 specifies the list of allowed performance classes for a system including a PMD and its external sensors: Table 3 – List of applicable system performance classes for PMD with external sensors 0,02

0,05

0,1

0,2

0,5

1

1,5

2

2,5

3

5

10

20

It is not allowed to specify a system performance class without specified external sensors. The requirements for the system performance for a PMD with a specified external sensor are the same as for a direct connected PMD. NOTE When a PMD Sx or a PMD xS is used with specified external sensors, the system performance class is based on the measured intrinsic uncertainty. When the sensors are not specified, the system performance class is equal to the uncertainty calculated according to  Ann ex D.

4.5

Operating and reference conditions for PMD

4.5.1 Reference conditions Table 4 gives the reference conditions for testing: Table 4 – Reference conditions for testing Conditions

Reference conditions

Operating temperature

23 °C ± 2 °C or otherwise specified by manufacturer

Relative humidity

40 % to 60 % RH

 Au xili ary sup pl y v olt ag e

Rat ed po wer sup pl y v olt age ±1 %

Phases

Three phases available a

Voltages unbalance

≤  0,1

External continuous magnetic field

≤  40 ≤  3

%a A/m d.c.

A/m ac at 50/60 Hz

D.c. component on voltage and current

None

Waveform

Sinusoidal

Frequency

Rated frequency (50 Hz or 60 Hz) ±0,2 % b

a

Required only in the case of three-phase systems.

b

PMD should use the standard rated frequencies of 50 Hz or 60 Hz, where possible, although other rated frequencies, or rated frequency ranges, including d.c., may be specified.

4.5.2 Rated operating conditions The tables below give the conditions in which functions shall be performed according to their specifications. 4.5.2.1

Rated temperature operating conditions for portable equipment

Table 5 gives the rated operating temperature for portable PMD:

BS EN 61557-12:2008

 – 22 – 

Table 5 – Rated operating temperatures for portable equipment K40 temperature class of PMD Rated operating range (with specified uncertainty)

4.5.2.2

0 °C to +40 °C

Limit range of operation (no hardware failures)

 –10 °C to +55 °C

Limit range for storage and shipping

 –25 °C to +70 °C

Rated temperature operating conditions for fixed installed equipment

Table 6 gives the rated operating temperature for fixed installed PMD: Table 6 – Rated operating temperatures for fixed installed equipment K55 temperature class of PMD

K70 temperature class of PMD

Kx b temperature class of PMD

Rated operating range (with specified uncertainty)

 –5 °C to +5 5 ° C

–25 °C to +7 0 ° C

Abo ve +7 0 ° C a nd/ or under –25 °C a

Limit range of operation (no hardware failures)

 –5 °C to +5 5 ° C

–25 °C to +7 0 ° C

Abo ve +7 0 ° C a nd/ or under –25 °C a

 –25 °C to +7 0 ° C

–40 °C to +85 °C

Acc . to ma nuf act ure r specification a

Limit range for storage and shipping a

Limits are to be defined by manufacturer according to the application.

b

Kx stands for extended conditions.

4.5.2.3

Rated humidity and altitude operating conditions

Table 7 gives the rated operating humidity and altitude for portable and fixed installed PMD: Table 7 – Humidity and altitude operating conditions Standard conditions

Extended conditions

Rated operating range (with specified uncertainty)

0 to 75 % RH b

0 to above 75 % Rh a b

Limit range of operation for30 days/year 

0 to 90 % RH b

0 to above 90 % RH a b

Limit range for storage and shipping

0 to 90 % RH b

0 to above 90 % RH a b

0 to 2 000 m

0 to above 2000 m a

Altitude a

Limits are to be defined by manufacturer according to the application.

b

Relative humidity values are specified without condensation.

The limits of relative humidity as a function of ambient temperature are shown in Figure 3.

BS EN 61557-12:2008

 – 23 – 

Climatic conditions that do not occur in practice

70

   )    C    °    (

50

  u

       θ

  e   r   u    t   a   r   e   p   m   e    t    t   n   e    i    b   m    A

25 23 21 Climatic conditions that do occur in practice

0 0

75

85

95

100

Relative humidity (%)

IEC 1274/07

Figure 3 – Relationship between ambient air temperature and relative humidity 4.6

Start-up conditions

Measurement readings shall be available via communications or local user interface 15 s after applying power supply. If the start-up is longer than 15 s, manufacturers shall specify the maximum time until measurement quantities shall be available via communications or local user interface after power supply is applied. When no communication or local user interface is available, this requirement shall be verified according to the test procedure given in 6.1.14. 4.7

Requirements for PMD functions (except PMD-A)

Subclause 4.7   describes a list of functions. Depending on the purpose of the measurement, all or a subset of the functions listed shall be measured.  Al l functions imple mented in the pro duct and covered by this standard shall comply with the requirements of this standard. 4.7.1 Active power ( P ) and active energy ( E a) measurements 4.7.1.1

Techniques

See  Annex A. Zero blind measurement is required. 4.7.1.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the following rated range: 80 %U n  < U   < 120 %U n

BS EN 61557-12:2008

4.7.1.3

 – 24 – 

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 8: Table 8 – Intrinsic uncertainty table for active power and active energy measurement Specified measuring range Value of current for Direct connected PMD Dx

Value of current for Sensor operated PMD Sx

Power factor d

Intrinsic uncertainty limits for PMD of function performance class C  a b c for C  < 1

for C  ≥  1

× C 

2 % I b

≤

I   < 10 %I b

1 % I n

≤

I  < 5 %I n

1

5 % I b

≤

I   < 10 %I b

2 % I n

≤

I  < 5 %I n

1

I  ≤ I max

1

I   < 10 %I n

0,5 inductive

±(1,7

× C  + 0,15)

No requirement

0,8 capacitive

±(1,7

× C  + 0,15)

No requirement

10 %I b 5 % I b

10 %I b

≤

≤

20 %I b

≤

I  ≤ I max

I   < 20 %I b

I   < 20 %I b

≤

I  ≤ I max

5 % I n 2 % I n

5 % I n

≤

≤

10 %I n

≤

I   < 10 %I n

≤

I  ≤ I max

±2,0

No requirement ±1,0

Unit

× C  

No requirement

%

× C   + 0,5)

%

× C 

%

±(1,0

±1,0

0,5 inductive

No requirement

±(1,0

× C   + 0,5)

0,8 capacitive

No requirement

±(1,0

× C   + 0,5)

0,5 inductive

±(1,0

× C   + 0,1)

±1,0

× C 

0,8 capacitive

±(1,0

× C   + 0,1)

±1,0

× C 

%

%

%

a

The permitted values for active energy function performance class C are: 0,2 – 0,5 – 1 – 2, the permitted values for active power funtion performance class C are: 0,1 – 0,2 – 0,5 – 1 – 2 – 2,5.

b

The permitted values and formula to calculate the system performance class of a PMD with an external current sensor or voltage sensor are given in  Ann ex D.

c

For active energy measurement class 1 and 2 of this standard, the uncertainty limits of classes 1 and 2 defined in Table 6 of IEC 62053-21 can be used as well as the uncertainty limits given in this table. For active energy measurement class 0,2 and 0,5 of this standard, the uncertainty limits of class 0,2S and 0,5S defined in Table 4 of IEC 62053-22 can be used as well as the uncertainty limits given in this table.

d

In reference conditions, signals are sinusoidal, so in this case power factor = cos

4.7.1.4

ϕ.

Limits of variations due to influence quantities

The additional variations due to influence quantities with respect to reference conditions as given in 4.5.1, shall not exceed the limits for the relevant performance class given in the Table 9:

BS EN 61557-12:2008

 – 25 – 

   K    K    /    /    %    %

   t    i   n    U

   t   n   e   m   e   r   u   s   a   e   m   y   g   r   e   n   e   e   v    i    t   c   a    d   n   a   r   e   w   o   p   e   v    i    t   c   a   r   o    f   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I   –    9   e    l    b   a    T

  r   e   o  c   n    f    t   a   n  m   e  r    i   o   c   f    i   r   b    f    f   e  a   e  p   o  n   C   c  o  s    i   s   e   r   t   a   u  c   n   l    t   c   u   a   r   f   e   f   p  o   m    D   e    T   M    P

   f   o    1    C    C    D       ≥   x   x    M  e   c    C    5    7    P  n   r   a    0   r    0  ,  ,   o  m   o    0    0    f    f   r   b   n   f   o  a   o  r   C    i    t   e  s   a  p  s    i   r   n  a   a  o   l    1    C   v   i   c    C    f   t    <   x   x   o  c   n    C    5    1   s  u  ,    i   r    0    t    f  ,   o    0    0    f   m    i    L

   j

  r   o    t   c   a    f   r   e   w   o    P

  e

  r   o    f    d   e    t   t   n  a   r   f   e   x   r   r   e    S   u  p   c  o   D    f   r    M   o  o   s   P   e  n   u  e    l   a   S    V

  e   g   n   a   r   g   n    i   r   u   s   a   e   r   o   m    f    d   e    d    t   t   e    i   n  c   f    f    i   e  e   n  x   c   r   n   D   e   r   u   p   c  o   D    S    f   c   M    t   o  c   P   e  e   r   u   i    l   a   D    V

  e   g   n   a   r   e   c   n   e   u    l    f   n    I   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I

  e   v    i    t   c   u    1    d   n    i    5  ,    0

  x   x   a   a   m   m    I    I        ≤

   I

       ≤

   I

   %    %

   %    %    %    %

   %

   4    6  ,    5  ,    2  ,    4  ,  ,    0    0    0    0    0    C    C    C       ≥    +    +    +    +    +    5   x  ,   x   x    C    C    C    C    C    C    1    1    0    0  ,  ,   x   r  ,   x   x   x   x    2    2   o    0    3    5    3    3    f    2  ,  ,  ,  ,  ,    0    0    0    0    0    1

   4    0  ,    1    0    C    <   x    +    C  ,    C   r    1    0   x   o    f    3  ,    0

   8    0  ,    0    +

   4    0  ,    0    +

   4    0  ,    0    +

   C    C    C

  x   x   x    6  ,    3  ,    3  ,    0    0    0

   2    3    0  ,  ,  ,    2    0    0    0    C    +    +    +   x    C    C    0    C   x   x  ,   x    2    5    5    4  ,  ,    1  ,    1    0    0

  e   e   v   v    i    i    t    t   c   c   u   u    1    1    d    1    d    1    1    1    1   n   n    i    i    5    5  ,  ,    0    0

  n    I

  x   x   x   x   a   a   a   a   m   m   m    I   m    I    I    I        ≤

       ≤

       ≤

       ≤

  x   a   m   n    I   n    I    %    I    %   n    I

  n   n    I    I

   %    %    5    0    1

   %    I    I    I    I    0        ≤        ≤        ≤        ≤    0   n    I   n    I   n    I   n    1    1    I    %    %    %    %    2    5    2    5

  x   x   a   a   m    I   m    I

  x   x   x   x   a   a   a   a   m   m   m    I    I   m    I    I

       ≤

       ≤

   I

       ≤

       ≤

       ≤

   I

       ≤

   b    I    b    I

   %    %    0    0    1    2

   5   e    l    d   b   a   e   T    t   a   r   f   o   6   o  e   l   e    t    b   g  g   n   a   n  a   T    i   r    d   r   g   &   o  n   c   i   c   t   a  a   r   e   p   o

   b    I

       ≤

       ≤

       ≤

       ≤

   0    5

  x   a   m    I

   b    I

   b    I    b    %    I    I    I    I    %    I        ≤        ≤    %    0        ≤    b        ≤    b    0    b    b    I    I    0    1    I    1    I    5    %    %    %    %    0    0    5    1    5    1

  n

   U

   %    %    5    1    0    ±    2   e    1   g    <   a    U    t    l   o    <   v   n    d    U   e    t    %   a   r    0    8

   %    2    ±   y   c   n   e   u   q   e   r    f    d   e    t   a   r

  g   :   :   n   c    i   c    i   s    i   n   s   n    i   o   o   m   m   m   r    %   s   r   a   a   e    0   s    h   %    h   %      1      h    h    0   a    t      t   o    h    5   0    4    t   p  ,    1    5  ,    t    0    2   e   n   r   g   e   a   r   o    t   r    l   e   o   u   c   n   v   o

   l

  e   p   y    t   e   c   n   e   u    l    f   n    I

  e   r   u    t   a   r   e   p   m   e    t    t   n   e    i    b   m    A

  e   g   a    t    l   o   v   y    l   p   p   u   s   r   e   w   o   p   y   r   a    i    l    i   x   u    A

  e   g   a    t    l   o    V

  y   c   n   e   u   q   e   r    F

  e   c   n   e   u   q   e   s   e   s   a    h   p    d   e   s   r   e   v   e    R

  e   c   n   a    l   a    b   n   u   e   g   a    t    l   o    V

   f

  g   n    i   s   s    i   m   e   s   a    h    P

   t   n   e   r   r   u   c   e    h    t   n    i   s    t   n   s   e   t   n   i   o  u   p  c   r    i   m   c   o  e   c   c   g   a    i    l   n   t   o  o   v   m   r   d   a  n    H  a

61557-12 4.7.1.5

�  IEC:2007

BS EN 61557-12:2008

 – 27 – 

Starting and no-load condition

4.7.1.5.1

Start-up of the PMD

See subclause 4.6. 4.7.1.5.2

No load condition (only for energy measurement)

When the voltage is applied with no current flowing in the current circuit, the test output of the PMD shall not produce more than one pulse. For this test, the current circuit shall b e open-circuit and a voltage of 115 % of the rated voltage shall be applied to the voltage circuit. NOTE

In the case of outside shunt, only the input circuit of the PMD shall be opened.

The minimum test period  Δt  shall be: Minimum test period Δ t   for no load condition

PMD types

for C  < 1 PMD

∆t  =

((100 / C ) k  × m

+ 400 ) × 10 6

× U n × I max

for C  ≥  1

min

∆t  =

(( 240 / C )

+ 360 ) × 10 6

k  × m × U n

× I max

min

where C 

is the function performance class;

k 

is the number of pulses emitted by the output device of the PMD per kilowatt-hour (imp/kWh);

m

is the number of measuring elements;

U n

is the rated voltage in volts;

I max

is the maximum current in amperes.

For transformer-operated PMD with primary or half-primary registers, the constant k   shall correspond to the secondary values (voltage and current). 4.7.1.5.3

Starting current

The PMD shall start and continue to register at the starting current values (and in the case of three-phase meters, with balanced load) shown in Table 10. When starting conditions are met (according to Table 10), intrinsic uncertainty shall be between –40 % and +90 % of measured values. If the PMD is designed for the measurement of energy in both directions, then this test shall be applied with energy flowing in each direction.

BS EN 61557-12:2008

 – 28 – 

Table 10 – Starting current for active power and active energy measurement PMD types

Power factor a

Starting current for PMD of function performance class C  for C  < 1

a

PMD Dx

1

PMD Sx

1

for C ≥  1

2 × 10

−3

× I b

(C  + 3 ) × 10

−3

× I b

1 × 10

−3

× I n

(C  + 1) × 10

−3

× I n

In reference conditions, signals are sinusoidal, so in this case power factor = cos

ϕ.

4.7.2 Reactive power ( Q A, Q V ) and reactive energy ( E rA , E rV ) measurements 4.7.2.1

Techniques

See  Annex A. Zero blind measurement is required. 4.7.2.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the following rated range: 80 %U n < U   < 120 %U n 4.7.2.3

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 11: Table 11 – Intrinsic uncertainty table for reactive power and reactive energy measurement Specified measuring range value of current for Direct connected PMD Dx 5 % I b

≤

10 %I b 10 %I b

a

≤

I   < 10 %I b ≤

I  ≤ I max .

I  < 20 %I b

value of current for Sensor operated PMD Sx 2 % I n

5 % I n

≤

Intrinsic uncertaint y limits for PMD of function performance class C  a b c for C  < 3

for C  ≥  3

Unit

I  < 5 %I n

1

±1,25 x C 

±1,33 x C 

%

I  ≤ I max

1

±1,0 x C 

±1,0 x C 

%

I   < 10 %I n

0,5

±1,25 x C 

±1,33 x C 

%

≤

5 % I n

sin φ (inductive or capacitive)

≤

20 %I b ≤ I  ≤ I max

10 %I n

≤

I  ≤ I max

0,5

±1,0 x C 

±1,0 x C 

%

20 %I b ≤ I  ≤ I max

10 %I n

≤

I  ≤ I max

0,25

±1,25 x C 

±1,33 x C 

%

The permitted values for reactive energy function performance class C   are: 2 – 3; the permitted values for reactive power function performance class C are: 1 – 2 – 3.

b   The

permitted values and formula to calculate the system performance class of a PMD with an external current sensor or voltage sensor are given in  Ann ex D.

c

For reactive energy measurement class 2 and 3 of this standard, the uncertainty limits of class 2 and 3 defined in Table 6 of IEC 62053-23 can be used as well as the uncertainty limits given in this table.

4.7.2.4

Limits of variation due to influence quantities

The additional variations due to change of influence quantities with respect to reference conditions as given in 4.5.1, shall not exceed the limits for the relevant performance class given in Table 12:

BS EN 61557-12:2008

 – 29 – 

   K    K    /    /    %    %

   t    i   n    U

   t   n   e   m   e   r   u   s   a   e   m   y   g   r   e   n   e   e   v    i    t   c   a   e   r    d   n   a   r   e   w   o   p   e   v    i    t   c   a   e   r   r   o    f   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I   –    2    1   e    l    b   a    T

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     ×

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  e   g   n   a   r   e   c   n   e   u    l    f   n    I

     ×

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 .    3   –    2   –    1   :   e   r   a    C

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   5  ,    5  ,    1    1

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       ≤

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   %    %    %    %

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   d    d   n   n   a   a    b

  e   e   s

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   b

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  y    b    d   e   c   u    d   n    i  ,   c   s   b   e   c   s   n   d   a   l   e    b   r   i    f   u    t   y   s   c    i    d  n   e    d  u   e  q    t   e   c   f   r   u    d   i   o   n   d   o  a    C  r   a    b

  c

   d

  y   e    t   u   n    l    i   a   a   v    t   r    t   e   u   c   p   n   n    i   u   r   e   e    h    t   w   o   s    l   a    t    l   a    l    t   e   s   w   a   e   s    l   a    t   a    d   e   e   s   n   u   o    d   e    b   e    b   n    l   a    l   c   a    h    3   s    2     s    t    3   s    5   e    0    t    2  ,    6  .  .   c  .   s    C   e    d    E    I   r   g   o  n    f   a   o   c  .   r    8   a  e   e   e  g    l   a   g   t    b    l   a   a    t   o    l   v    T   o  y   v   l   n    i   y   p    l    d   p  p   u   e   p  s   n    i   u   d    f   s   e   e    d   e   i    f    i    h    3    t   c    f   e    d   o  p   n   a   e  s   g  e    2   n   h    t   a   s   r   l    l   s   r   a   a    l   e   r   c   g   o   r   f    f   a   o    l    t   n   s   a  e    t    i    f   m   m   o  e    i    l   r   e   i   n   s   u   a  q   o    i   c   e    t   a    i   e  r   r   e    h    t   h   a    t   v   n    I   h   e  .    t    i    h    t   e  w   g  ,   a  y    d    t   r    l    l   a   o  p    d   v   m   n   y   o   a   c    l    t   p   l   s   p   l   a   s   u   h    i   s   s    h    t   s   D    f   n    i   o   a   M    P    3   m  ,    d   y   e   n   s    b   a    d  a   c    2   e   r   y   s   e   n   s   w  a   a    l   o  n   c   p   I    t  .   n    D  e   e    M  g   m    P  n   a   e   r   a  r   u   s   r   s   o   i    h    f   a    t   e  .    d   f   e    l   m   e  o    l   y   b    t    t   e   a   u   g   r   t   e   s   l   e   i   s   e  a   v   n   h   r   t   e   t   a  u   e   i   n   s   p    t   n   v    i    t   n    i    i   m  r   c   e    i   a   i   v    l   e   e  g   e  p   r   p   r   t   s   s   e  u   o   i    h    F  m    T   d   n    l    f   a   e    i

BS EN 61557-12:2008

4.7.2.5

 – 30 – 

Starting and no-load condition

4.7.2.5.1

Start-up of the PMD

See subclause 4.6. 4.7.2.5.2

No load condition

When the voltage is applied with no current flowing in the current circuit, the test output of the PMD shall not produce more than one pulse. For this test, the current circuit shall b e open-circuit and a voltage of 115 % of the rated voltage shall be applied to the voltage circuit. NOTE

In case of outside shunt, only the input circuit shall be open circuited.

The minimum test period  Δt shall be: Minimum test period Δ t   for no load condition

PMD types

for C  < 3 PMD

∆t  =

(( 240 / C ) k  × m

+ 360 ) × 10 6

× U n × I max

for C  ≥  3

min

∆t  =

((1 080 / C ) – 60 ) × 10 k  × m × U n

× I max

6

min

where C 

is the function performance class;

k 

is the number of pulses emitted by the output device of the PMD per kilovar-hour (imp/kvarh);

m

is the number of measuring elements;

U n

is the rated voltage in volts;

I max

is the maximum current in amperes.

For transformer-operated PMD with primary or half-primary registers, the constant k   shall correspond to the secondary values (voltage and current). 4.7.2.5.3

Starting current

The PMD shall start and continue to register at the starting current values (and in case of three-phase meters, with balanced load) shown in Table 13. When starting conditions are met (according to Table 13) intrinsic uncertainty shall be between –40 % and +90 % of measured values. If the PMD is designed for the measurement of energy in both directions, then this test shall be applied with energy flowing in each direction.

BS EN 61557-12:2008

 – 31 – 

Table 13 – Starting current for reactive energy measurement PMD types

sin φ  (inductive or capacitive)

Starting current for PMD of function performance class C  for C  < 3  

for C  ≥  3

PMD Dx

1

(C   + 3)

×  1 0 –3 × l b

(5

× C   – 5) ×  1 0 –3 × l b

PMD Sx

1

(C   + 1)

×  1 0 –3 × l n

(2

× C   – 1) ×  1 0 –3 × l n

4.7.3 Apparent power ( S A, S V ) and apparent energy ( E ap A, E apV ) measurements 4.7.3.1

Techniques

See  Annex A. Zero blind measurement is required. 4.7.3.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the following rated range: 80 %U n  < U   < 120 %U n 4.7.3.3

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed the limits given in Table 14: Table 14 – Intrinsic uncertainty table for apparent power and apparent energy measurement Specified measuring range

a

Intrinsic uncertaint y limits for PMD of function performance class C  a b

Value of current for Direct connected PMD Dx

Value of current for Sensor operated PMD Sx

5 % I b  < I  ≤  10 %I b

2 % I n < I  ≤  5 %I n

±2,0

× C  

10 %I b  < I  ≤ I max .

5 % I n < I  ≤ I max

±1,0

× C  

for C  < 1

Unit

for C  ≥  1 ±(1,0

× C + 0,5)

%

× C 

%

±1,0

The permitted values for function performance class C are: 0,2 – 0,5 – 1 – 2

b  The

permitted values and formula to calculate the system performance class of a PMD with an external current sensor or voltage sensor are given in Ann ex D.

4.7.3.4

Limits of variation due to influence quantities

The additional variations due to change of influence quantities with respect to reference conditions as given in 4.5.1, shall not exceed the limits for the relevant performance class given in Table 15:

BS EN 61557-12:2008

   K    /    %

   t    i   n    U

   t   n   e   m   e   r   u   s   a   e   m   y   g   r   e   n   e    t   n   e   r   a   p   p   a    d   n   a   r   e   w   o   p    t   n   e   r   a   p   p   a   r   o    f   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I   –    5    1   e    l    b   a    T

 – 32 – 

  r   e   o  c   n    f    t   a   n  m   e  r    i   o   c   f    i   r    f    f   e  a   e  p   C   o  n   c  o  s    i   s   e   a   r   t    l   u  c   n  c    t   u   a   r   f   e   f   p  o   m    D   e    T   M    P

   1    C       ≥

   C

     ×

   5   r    0  ,   o    f    0

   1    C    <      ×    C    5   r    0  ,   o    0    f

  e

  r   o    t   c   a    f   r   e   w   o    P

   1

  r   o   d    f   e    t   t   n  a   e   r   r   x    d   r   e    S   p   e   u   c  o    D   g    f   r   n   o  o    M    P   a   r   e  s   n   u  e   g    l   n   a   S    i   r    V   u   s   a   e   r   o   m   f    d   e    d    t    t   e    i   n   c    f   x    i   e   e   n   D   c   r   n   e   r    D   p   u   c   o   c    S   f    t   M   o   c   P   e   e   r   u    i    l   a    D    V

  e   g   n   a   r   e   c   n   e   u    l    f   n    I   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I

  x   a   m    I        ≤

   I

       ≤

  n    I

   %    5

  x   a   m    I        ≤

   I

       ≤

   b    I

   %    0    1

   5   e    l    d   b   e  a    t    T   a    6   r   f   o  e   o    t   e   l    b   a   g  g   n   T   n    i   a   r    d   r   g   d   o  n  n   c   i   a   c   t    A  a   r   e   p   o

   %    %    f   o    D    M  e   c    P  n   r   a   o  m    f   r   b   n   f   o  a   o  r   C    i    t   e  s   a  p  s    i   r   n  a   a  o   l   v   i   c    f   t   o  c   n   s  u    t    f    i   m    i    L

   1       ≥

   %

   %    %

   4  ,    5  ,    0  ,    0    0    1    C    +    +    +

   0  ,    0  ,    1    1    +    +    C    C

     ×

   C    C    C  ,      ×      ×      ×   r    1   o    0    3    5    0    f  ,  ,  ,    0    0    1    C

   4    0  ,    1    0    C    <      ×    +    C    C  ,   r    1    0      ×   o    f    3  ,    0

  e   p   y    t   e   c   n   e   u    l    f   n    I

     ×

  n    I

       ≤

     ×

   f

   1    1

  n    I   n    I

  x   x   a   a   m   m    I    I        ≤

   I

       ≤

   I

   b    I    b    I

  n

  e   g   a    t    l   o   v   y    l   p   p   u   s   r   e   w   o   p   y   r   a    i    l    i   x   u    A

  e

     ×

       ≤

   b    %    I        ≤    0        ≤    b    b    I    1    I    %    %    5    0    1

   %    5    1    ±   e   g   a    t    l   o   v    d   e    t   a    R

  s   o   c   =   r   o    t   c   a    f   r   e   w   o   p   e   s   a   c   s    i    h    t   n    i   o   s  ,    l   a    d    i   o   s   u   n    i   s   e   r   a   s    l   a   n   g    i   s  ,   s   n   o    i    t    i    d   n   o   c   e   c   n   e   r   e    f   e   r   n    I

   3  ,    3  ,    0    0    +    +    C    C

  x   x   a   a   m    I   m    I

  n    %    I    I    I    0        ≤        ≤    1    I   n    I   n    %    %    2    5

   b    I

     ×

   0  ,    0  ,    1    1

   4  ,    4  ,    3    3

   6  ,    0

  e   v    i    t   c   u    1    1    d    1   n    i    5  ,    0

   U

   %    0    2    1    <    U    <   n    U

   d

   d

   d   n   a

   d    d   n   n   a   a

  c

  c

  c

  e   e   s

  e   e   s

  e   e   s

   %    0    8

   f

  e   r   u    t   a   r   e   p   m   e    t    t   n   e    i    b   m    A

   8    0  ,    0    +    0  ,    C    2

     ×

   t   u   p   n    i   r   e   w   o    l    t   a    t   s   a   e    l    t   a   e   n   o    d   e    b    l    l   a    h   s   s    t   s  .   e  s    t   e  ,   g  .   n   c  .   a    d  r   r   e   o  g   a   c    l  .    t   a  o   v   e  y   g   l   a  p    t    l   p   o  u   v   s   y   d    l   e   p   i   p   f    i   u  c   s   e   e  p   s    h    t   e    f   h   o   t    l   e   l   g  a   n  r   o   a   r   f    t   r   n   e  e   g   r   m   a  e    l   r    i   a  u    f   q   o  e   r   e  e   s   h   a   t   c    h   e   t    i    h    t   w   y   n   l    I  .   p   e  m   g  o   a  c    t    l    l    l   o  a   v   h   y   s    l   p   D   p   M   u   P   s  ,   s   e   n  s    i   a  a   c   m  y   y   n    b  a    d   I   n   e   r  .   e  e   w  g   o  n   p  a   r   s    D   i    h    M    t    P   f   a  o   r   e   u   o   l    f   a    d  v   e    t    l    t   u    t   e  p   n   s   i   r   e   r   e   a  p   s   p    t    i   u    d   m    i    l   n   a   e  e   s   u   e   l    h  a    T  v

  e   g   a    t    l   o    V

   f   o   n   o    d    i    t   c   c   u   s    d   d    d    l   n    i   c    i   e   c   T    f    i    t   m    F   e   5    R   n  ,   g   0    i   c   a  n    t    i   m  g   e   n   s   i   r   g   u  o   a   o   l   m   u  a   o   n  n   r    i    t   r    t   e   c   n   t   e   o  x    l    C  e    E

   d

 .   n   o    i    t   a   c   o    l    l   a    i   r    t   s   u    d   n    i  .   o  .    2    t   s   –   g    t   n   n    1    i    t   e   a   m   –    l   e   e    5  ,   r   r    0    d   u   s   –   r   a   a   e    2  ,    d   m   n    0   a   y   :    t   g   s   e   r    6   r   a    2   e   n    C    3   e   r   s    1   o   s    6    f  .   a    l    C    l   y    d   c    I   e    E   n    i    i   e   n   o    f   c    i   e   c   e   n    l   a    d    b   p   e   a   s   m   n    i   r    i   c   e    f   o   e    l    i   s    f   r    d   p   p   w   e   a   r   p   e   e   r    h   n   a   e   r    t   o   a   o    i    t   s   s   s   c   n   o    i   e   s   n    i    t   e    t   u    i    i    l    f    t   n    d   r   n   n   u   o   o   a    f   c   u    d   s    t   q   e   e   s   e   c   u   e   c   n    l   a   a    t   n    l   v    d   e   a   u    b    d   n    l   e   a    f    t   n   e   r   s    i    t    i    l   a   e    C    t   m   s   r   v   e    M   n   e    l   p    E   e   r   e    C   e   r    h    M    h   u    T    E    T    C

  y    b    d   e   c   u    d   n    i  ,   s   d   e  c   c   s   n   d   a   l   e    b   r   i    f   u    t   y   s   c    i    d  n   e    d  u   e  q    t   e   c   f   r   u    d   i   o   n   d   o  a    C  r   a    b

  c

   d

 .      ϕ

BS EN 61557-12:2008

 – 33 – 

4.7.4 Frequency (f ) measurements 4.7.4.1

Techniques

Zero blind measurement is not required. 4.7.4.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the following rated range:  –

Voltage:

50 %U n  to U ma x; or

 –

Cur re nt:

for PMD Dx:

20 %I b to I max, for PMD Sx:

10 %I n to I ma x

NOTE Frequency is usually measured from voltage function of PMD; current rated range of operation has to be considered only if this function does not exist in the PMD.

4.7.4.3

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 16: Table 16 – Intrinsic uncertainty table for frequency measurement Intrinsic uncertainty limits for PMD of function performance class C  a b

Specified measuring range 45 Hz to 55 Hz or 55 Hz to 65 Hz

±1,0

× C 

Unit %

a

The permitted values for function performance class C   are: 0,02 – 0,05 – 0,1 – 0,2 – 0,5.

b

The permitted values and formula to calculate the system performance class of a PMD with an external CS or VS are given in  Ann ex D.

4.7.4.4

Limits of variation due to influence quantities

The additional variations due to change of influence quantities with respect to reference conditions as given in 4.5.1, shall not exceed the limits for the relevant performance class given in Table 17: Table 17 – Influence quantities for frequency measurement Influence quantities Influence type  Am bie nt tem per at ure

Influence range or influence level Acc ord ing to rat ed operating range of Table 5 and Table 6

Temperature coefficient for PMD of function performance class C  a 0,1

× C 

Unit

%/K

Limits of variation for PMD of function performance class C  a

Voltage Harmonics in the voltage circuits b

50 %U n t o U max

0,2

× C 

%

3rd  harmonic 10 %

0,2

× C 

%

5 th  harmonic 12 % 7 th  harmonic 10 % 9th  harmonic 3 % 11 th  harmonic 7 % 13 th  harmonic 6 % 15 th  harmonic 1 % a b

The permitted values for function performance class C   are: 0,02 – 0,05 – 0,1 – 0,2 – 0,5  All h armonic s com ponent s ha ve th e same relati ve ph ase, but i n opp osite phase referre d to the f undam ental .

BS EN 61557-12:2008

 – 34 – 

4.7.5 R.m.s. phase current (I ) and neutral current (I N , I Nc ) measurements 4.7.5.1

Techniques

See  Annex A. Zero blind measurement is not required. 4.7.5.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the rated ranges given in Table 18 and Table 19: 4.7.5.2.1

Rated range of operation for phase current Table 18 – Rated range of operation for phase current measurement

PMD types

Specified measuring range

Minimum bandwidth (harmonic)

PMD Sx

10 %I n to 120 %I n

45 Hz to 15 times rated frequency or

Crest factor 2

d.c. and 45 Hz to 15 times rated frequency PMD Dx

20 %I b  t o I max

45 Hz to 15 times rated frequency or

2

d.c. and 45 Hz to 15 times rated frequency

4.7.5.2.2

Rated range of operation for measured neutral current (with a sensor) and calculated neutral current (from phase currents) Table 19 – Rated range of operation for neutral current measurement

PMD types

Specified measuring range

Minimum bandwidth (harmonic)

PMD Sx

10 %I n to 120 %I n

45 Hz to 15 times rated frequency or

Crest factor 2

d.c. and 45 Hz to 15 times rated frequency PMD Dx

20 %I b  t o I max

45 Hz to 15 times rated frequency or

2

d.c. and 45 Hz to 15 times rated frequency

NOTE

The nominal current of the neutral current sensor may be different from the one for phase current sensor.

4.7.5.3

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 20, Table 21 and Table 22.

BS EN 61557-12:2008

 – 35 – 

4.7.5.3.1

Intrinsic uncertainty table for phase current Table 20 – Intrinsic uncertainty table for phase current Specified measuring range value of current for Direct connected PMD Dx 20 %I b

≤

I  ≤ I max

value of current for Sensor operated PMD Sx 10 %I n

≤

Intrinsic uncertainty limits for PMD of function performance class C  a b

Unit

±1,0 x C 

%

I  ≤ I max

a

The permitted values for function performance class C   are: 0,05 – 0,1 – 0,2 – 0,5 – 1 – 2.

b

The permitted values and formula to calculate the system performance class of a PMD with an external current sensor are given in  Ann ex D.

4.7.5.3.2

Intrinsic uncertainty table for measured neutral current (with a sensor) Table 21 – Intrinsic uncertainty table for neutral current measurement Specified measuring range value of current for Direct connected PMD Dx 20 %I b

≤ I N ≤ I max .

value of current for Sensor operated PMD Sx 10 %I n

Intrinsic uncertainty limits for PMD of function performance class C  a b

≤ I N ≤ I max

±1,0

× C 

Unit

%

a

The permitted values for function performance class C   are: 0,2 – 0,5 – 1 – 2.

b

The permitted values and formula to calculate the system performance class of a PMD with an external current sensor are given in  Ann ex D.

4.7.5.3.3

Intrinsic uncertainty table for calculated neutral current (from phase currents) Table 22 – Intrinsic uncertainty table for neutral current calculation Specified measuring range value of current for Direct connected PMD Dx 20 %I b

4.7.5.4

≤ I p c ≤ I max .

value of current for Sensor operated PMD Sx 10 %I n ≤ I p c

Intrinsic uncertainty limits for PMD of function performance class C  a b d

≤ I max

±1,0

× C 

Unit

%I c

a

The permitted values for function performance class C   are: 0,1 – 0,2 – 0,5 – 1 – 2.

b

The permitted values and formula to calculate the system performance class of a PMD with an external current sensor are given in  Ann ex D.

c

Uncertainty shall be expressed as a percentage of the phase current, whose current is the largest.

d

Performance class C  refers to Phase current performance class.

Limits of variation due to influence quantities

The additional variations due to change of influence quantities with respect to reference conditions as given in 4.5.1, shall not exceed the limits for the relevant performance class given in Table 23:

BS EN 61557-12:2008

   t    i   n    U

   t   n   e   m   e   r   u   s   a   e   m    t   n   e   r   r   u   c    l   a   r    t   u   e   n    d   n   a    t   n   e   r   r   u   c   e   s   a    h   p   r   o    f   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I   –    3    2   e    l    b   a    T

  r   e   o  c   n    f    t   a   n  m   e  r    i   o   c   f    i   r    f    f   e  a   e  p   C   o  n   c  o  s   s   e   i   a   r   t   c   l   u    t   n  c   a   u   r   f   e   f   p  o   m   e   D    T   M    P

   b

  r   o  x   s   S   n   e   D    S   M    t   P   n   d   e  e   r   r   t   u  a   c  r   e   r   p   o  o    F

  e   g   n   a   r   g   n    i   r   u   s   a   e   x   m    t   c   D    d   e   r   D   e    i    i    f    i    D   M   c    t   P   e   n   d   p   e  e    S   r   r   t   u  c   c  e   r   n   o  n    F  o   c

  e   g   n   a   r   e   c   n   e   u    l    f   n    I   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I

   K    /    %

   C      ×

   5    0  ,    0

  x   a   m    I        ≤

   I

       ≤

  n    I

   %    0    1

  x   a   m    I        ≤

   I

       ≤

   b    I

   %    0    2

   5   e    l    d   b   e  a    t    T   a    6   r   f   o  e   o  e   l    t    b   a   g  g   n   T   n    i   a   r    d   r   g   d   o  n  n   c   i   a   c   t    A  a   r   e   p   o

 – 36 – 

   %

   f   C   o    D  s   s   a    M    l    P  c   r   e   o  c    f   n   n  a   o    i    t   m   r  a   a  o    i    f   r   r   a  e   v    f   p   o  n   o   s   i    t    i   t   c   m  n    i   u    L   f

   C      ×

   1  ,    0

  n    I

   %    0    1

   b    I

   %    0    2

   %    5    1    ±   e   g   a    t    l   o   v    d   e    t   a    R

  c

  e   p   y    t   e   c   n   e   u    l    f   n    I

  e   r   u    t   a   r   e   p   m   e    t    t   n   e    i    b   m    A

  e   c   n   a   m   r   o    f   r   e   p   n   o    i    t   c   n   u    f   r   o    f   s   e   u    l   a   v    d   e    t    t    i   m   r   e   p   e    h    T    2   –    1   –    5  ,    0   –    2  ,    0   :   e   r   a    t   n   e   r   r   u   c    l   a   r    t   u   e   n    d   e   r   u   s  .   a   2   e  –   m   r   1   o  –    f    5  ,    C    0   s   –   s   a   2    l  ,   c   0   e  –   c   1   n  ,   a   0   :   m   r   e   r   o    f   a   r   t   e  n   p  e   n  r   o  r   u    i    t   c   c   l   n  a   r   u   t    f   r   u   o  e    f   n   s   d   e   e   t   u  a    l    l   a  u   v   c    d   l   e  a   c    t    t    i   r   o    f   m   r   e   C   p  s   e  s   a    h   l    T  c

  e   g   a    t    l   o   v   y    l   p   p   u   s   r   e   w   o   p   y   r   a    i    l    i   x   u    A   a

   t  .   a  s   e  e   n  g   o  n    d  a   r   e    b  e    l   g   a    l    l   a   t    h  o   s   v   y   s   l    t   s   p   e  p    t   u  ,  .   s   c  .   d   e    d   i    f   r   i   o  c   e   c  .   p   s   a   e   e   h   g   t    l   a   l    t    l   a   o  r   v   o   y   f    t    l   p  n   p  e   u  m   s   e  .   r   e   i   m    h   u    t   e   q    t    f   s   o  e   r   y   s   e  e    h   n   g   t   o   n   h    i    t   a    t   u   r   i   r   w    b    i   r   e   l   y    t   g   s   r   p    i   a    d    l   m   e   a  o   c   s    f   l   a    l    h   o  a   p    h   -   e   s   e   s   a   e   c    D   r    h    t   e   M    t   P   n    h  ,    i   n  e   s    I   s    t   n  .   a   e  c   e   r   r   g   a  y   n   u    t   c    l   o  a   n    d   v   I   e   y  .   c    l   e   n   p  g   a   p  n    l   a   u  a    b   s   r   s   i   s    h    t   n   h    i    i    t   a   w    f    d   m  o   e   y   e   n    i   u    f    b   l   e    d  a   v    d   e   r   t   e   u   r   e   a   w  p   n    t   o    i   n   p  r   e   e   r   r    D   p   u    M  p   c    P  u   e   a   d   s   r   n   a   o  a    h    f   e   p   u   r    d    l   e   o    l   a    f    t    t   v   s   e   t   e   s   u    i    t    i   e  p    t   n    i   n   r   a   a  r   s   e   u    t   q    i   w   o   m    l   e    i   c    l    t   n   e  a   e   s   t   u   e  s    l    f    h   a   n    T   l   e    I    b

  c

BS EN 61557-12:2008

 – 37 – 

4.7.6 R.m.s. voltage ( U ) measurements 4.7.6.1

Technique

See  Annex A. Zero blind measurement is not required. 4.7.6.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the rated ranges given in Table 24: Table 24 – Rated range of operation for r.m.s. voltage measurement PMD types

Specified measuring range

Minimum bandwidth (harmonic)

PMD xS

20 %U n  to 120 %U n

45 Hz to 15 times rated frequency or

Crest factor 1,5

see NOTE

d.c. and 45 Hz to 15 times rated frequency PMD xD

As specified by manufacturer

45 Hz to 15 times rated frequency or

1,5

d.c. and 45 Hz to 15 times rated frequency NOTE Between 20% of U n   and 50% of U n , PMD using frequency detection circuits not operating in all the rated range can measure voltage with the last consistent measured value of frequency.

4.7.6.3

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 25: Table 25 – Intrinsic uncertainty table for r.m.s. voltage measurement Specified measuring range Value of voltage for Direct connected PMD xD U mi n

4.7.6.4

≤

U  ≤ U max c

Value of voltage for Sensor operated PMD xS U mi n

≤

Intrinsic uncertainty limits for PMD of function performance class C  a b

U  ≤ U max c

±1,0

× C 

Unit

%

a

The permitted values for function performance class C   are: 0,05 – 0,1 – 0,2 – 0,5 – 1 – 2

b

The permitted values and formula to calculate the system performance class of a PMD with an external CS or VS are given in  Ann ex D.

c

Manufacturer can define U max and U mi n, taking into account minimum measuring range of Table 24.

Limits of variation due to influence quantities

The additional variations due to change of influence quantities with respect to reference conditions as given in 4.5.1, shall not exceed the limits for the relevant performance class given in Table 26:

C BS EN 61557-12:2008

   K    /    %

   t    i   n    U   r   e   o  c   n    f    t   a   n  m   e  r    i   o   c   f    i   r    f    f   e  a   e  p   C   o  n   c  o  s   s   e   i   a   r   t    l   c   u  n  c    t   a   u   r   f   e   f   p  o   m   e   D    T   M    P

   t   n   e   m   e   r   u   s   a   e   m   e   g   a    t    l   o   v  .   s  .   m  .   r   r   o    f   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I   –    6    2   e    l    b   a    T

   b

  e   g   n   a   r

   C      ×

   5    0  ,    0

  r   o   d   x    f   a   e   e   t   m   g  a   r   S    U   a    t   x        ≤    l   e   o  p   o    U    D   v        ≤    f   r    M   o  o   s   P    i   n   e  n   m   u   e    l    U   a   S   v

  g   n    i   r   u   s   a   e   r   m    f   o   d   x   e   a    d   e   t   e   g  c   m    i    f   e   a    D    U    i    t   n   c    l   x        ≤   e   o  n   p   v  o   D    U    S    f   c   M        ≤   o   t   n   c   P    i   e  e   m   r   u    l   i    U   a   D   v

  e   g   n   a   r   e   c   n   e   u    l    f   n    I   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I

  e   p   y    t   e   c   n   e   u    l    f   n    I

   5   e    l    d   b   e  a    t    T   a    6   r   f   o   e   o    t   e   l    b   a   g  g   n   T   n    i   a   r    d   r   g   d   o  n   n   c   i   a   c   t    A  a   r   e   p   o

  e   r   u    t   a   r   e   p   m   e    t    t   n   e    i    b   m    A

   f   o    D    M  e   c    P  n   r   a   o  m    f   r  a   n   f   o   C   o   r    i    t   e  s   a  p  s    i   a   r   n   l   a  o  c   v   i    f   t   o  c   n   s  u    t    i   f   m    i    L

 – 38 – 

   t   a    t   s    %   a   e    l    t   a   e   n  .   o  s    d  e   e  g    b  n   a    l    l   r   a  e    h  g    C   s   t   a      ×   s   l    t   o    1   s   v  ,   e   y    0    t   l  ,  .   p   p   c  .   u    d  s   r   d   o  e    i   c    i  .    f   a  c   e   e  p   g  s   a  e    t    l   o   h   x   a   v   t    l    l   m   y   a    l    U   p  r   o   p   f        ≤   u   t   s   n    U  .   c   e        ≤    4    i   m   n   m  e    2    i   r   e   a   m    l   n   i    U    b   y   u   a    d  q    T   e  e   r    f   g   o   r   e    h   a   t   e    l   g   a   h   x   n    f   t    i   a   a   m  .   r   o   w    U    2   g   e   l   y   n   s   p   –    i        ≤   a   r    U    1   u   c   m   s   e  o   –        ≤   c   a    h   l    5    t   l   n  ,   e    i    0   m   n  a    I   m   –    d  .    h   s    U   e    2    i   e  ,    f    D   g    0    i   c   a   M    l    P   –   e    t   p   o  ,    1  ,   s   v   e    0    t    l   y   s   a    %   :   n   u   p   c   e    5   r   o   p  y    1   a   c   u   s   n    ±   c   a   e    C   a   s   n   I   n   g   s   o    i    t   a   a   s  .    t   n   a    l    l    i   m  e   o   c   g   g   v   e   n   y   n    b  a    d   c    i   e   n    k    d  r   a    t   e  s   a   a    t  ,   r   i    R   m   n   e   h    t   r    i   o   m   w   f    f   o   o   r    U   p  e   e   p    d    D   l   u   n   n   a   a    M   o   c    i   v    P   t    t   x   e   c   a   a  u   g   n   m   r   p   a   u    t   n    U    f   o   i    l    f   o   r   e   r   v    f   o   n    d  e    i   e   p   y   s    f    l    l   e    t    t   p   p   e    d   u   e   p    l   u   u   a   n   s   d   s   v   a   e  n   r   c   r   a   e    d   r   a  e   e   w    t   e   s   l   u    t   o    t    i   r   u    i   a   p   m    t   m  v   c    i    l    t   y   a   r   r   e   u   a   p    f   u   e  p    i    l    i   e   n   s   n   e    i   x    h   a    h   u    T    M    T  r   e    A   w   o   a    b   c    l

BS EN 61557-12:2008

 – 39 – 

4.7.7 Power factor (PF A, PF V) measurements 4.7.7.1

Techniques

See  Annex A. 4.7.7.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the following rated ranges:  –

Voltage:

50 %U n to U ma x or;

 –

Cur re nt:

for PMD Dx: for PMD Sx:

4.7.7.3

20 %I b to I max 10 %I n to I max

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 27: Table 27 – Intrinsic uncertainty table for power factor measurement

Specified measuring range

Intrinsic uncertainty limits for PMD of function performance class C  a b

From 0,5 inductive to 0,8 capacitive

±0,1

Unit c

× C 

a

The permitted values for function performance class C   are: 0,5 – 1 – 2 – 5 – 10.

b

The permitted values and formula to calculate the system performance class of a PMD with an external current sensor or voltage sensor are given in  Ann ex D.

c

No units.

4.7.7.4

Limits of variation due to influence quantities

The additional variations from intrinsic uncertainties shall be calculated according to Table 9 and Table 15 for power factor 1 and 0,5 inductive, within the rated ranges of operation, taking into account the worst case combination of uncertainties. 4.7.8 Short term flicker (P st ) and long term flicker ( P lt ) measurements 4.7.8.1

Techniques

See IEC 61000-4-15. 4.7.8.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the following rated range:  –

Voltage:

4.7.8.3

80 %U n  to U ma x

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 28: Table 28 – Intrinsic uncertainty table for flicker measurement Specified measuring range

From 0,4 to 2 a

Intrinsic uncertain ty limits for PMD of function performance class C  a ±1,0

× C 

The permitted values for function performance class C   are: 0,5 – 1 – 2 – 5 – 10.

Unit

%

BS EN 61557-12:2008

 – 40 – 

4.7.9 Voltage dip ( U dip ) and voltage swell ( U swl ) measurements 4.7.9.1

Techniques

See  Annex A. Zero blind measurement is required. Requirements in 5.4 of IEC 61000-4-30 apply, with the following modifications:  –

in this par t, either a fixed reference vol tage or a slidi ng refere nce voltage with a oneminute time constant first order filter are required as threshold value for voltage dips or voltage swells detection;

 –

in this part, a synchronisation on zer o cross ing of voltage fundament al is not require d.

4.7.9.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the rated ranges given in Table 29: Table 29 – Rated range of operation for voltage dips and swells measurement PMD types

Minimum threshold range settable for voltage dip

Minimum threshold range settable for voltage swell

PMD xS

From 5 %U n to 100 %U n

from 100 %U n to 120 %U n

PMD xD

As specified by manufac turer

as specified by manufactu rer

Minimum detectable duration shall be equal at least to one period of the measured voltage. 4.7.9.3

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 30: Table 30 – Intrinsic uncertainty table for voltage dips and swells measurement

Specified measuring range

Intrinsic uncertainty limits for PMD of function performance class C  a b c

Dips, residual voltage and s wells overvoltage Dips duration and swells duration

±1,0

× C 

One period at the network frequency

Unit %U n ms d

a

The permitted values for function performance class C   are: 0,1 – 0,2 – 0,5 – 1 – 2.

b

The permitted values and formula to calculate the system performance class of a PMD with an external voltage sensor are given in  Ann ex D.

c

The uncertainty of a dip or swell duration is equal to the dip or swell commencement

uncertainty (half a cycle) plus the dip or swell conclusion uncertainty (half a cycle). d

4.7.9.4

This is a fixed uncertainty.

Limits of variation due to influence quantities

The additional variations due to change of influence quantities with respect to reference conditions as given in 4.5.1, shall not exceed the limits for the relevant performance class given in Table 31:

 – 41 – 

   K    /    %

   t    i   n    U   r   e   o  c   n    f    t   a   n  m   e  r    i   o   c   f    i   r    f    f   e  a   e  p   C   o  n   c  o  s   s   e   i   a   r   t    l   c   u  n  c    t   a   u   r   f   e   f   p  o   m   e   D    T   M    P

   t   n   e   m   e   r   u   s   a   e   m   s    l    l   e   w   s    d   n   a   s   p    i    d   r   o    f   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I   –    1    3   e    l    b   a    T

   b

  e   g   n   a   r

   C      ×

   5    0  ,    0

  r   o   d   x    f   a   e   e   t   m   g  a   r   S    U   a    t   x        ≤    l   e   o  p   o    U    D   v        ≤    f   r    M   o  o   s   P    i   n   e  n   m   u   e    l    U   a   S   v

  g   n    i   r   u   s   a   e   r   m    f   o   d   x   e   a    d   e   t   m   e   g  c    i    f   a  e   D    U    i    t   c    l   n  x        ≤   e   o  n   p   v  o   D    U    S    f   c   M        ≤   o   t   c   P    i   n   e  e   r   m   u    l   i    U   a   D   v

  e   g   n   a   r   e   c   n   e   u    l    f   n    I   s   e    i    t    i    t   n   a   u   q   e   c   n   e   u    l    f   n    I

  e   p   y    t   e   c   n   e   u    l    f   n    I

   5   e    l    d   b   a   e   T    t   a    6   r   f   o  e   o  e   l    t    b   a   g  g   n   T   n    i   a   r    d   r   g   d   o  n  n   a   c   t    i   c   a  a   r   e   p   o

  e   r   u    t   a   r   e   p   m   e    t    t   n   e    i    b   m    A

   t  .   a  s   e  e    U    U   n  g    %    %   o  n    d  a   r   e  e    b  g    l   a    l    t   a   l    h  o   s   v   y   s   l    t   s   p   e  p    t   u  ,    C    C  .   s    d   c      ×      ×  .   e    d   i    f    1  ,    5  ,   r   i    0    0   o  c   e   c  .   p   s   a   e   e   h   g   t   a   l    l    t    l   a   o  r   v   o   y   f    t    l   p  n   p  e   x   x   u  m   a   a   s   e   m   m   r   e   i    U    U   u    h    t   q        ≤        ≤    f   e   o  r    U    U   e        ≤        ≤  .   e   h    t    9   g   n   n   n    i    i    2   a   h    t   m   m   e   r   i    l    U    U   r    b   e  w   y   a   r   l    T   g   p   a    f    l   m   o   a  o   e    f   c   g   o   l   x   x    l   n   a   a   a   m   m  .   a    h   r   e   s   s    U    U    2   a   –   g        ≤        ≤   n   c   D    i   r    1   e   M    U    U    P   –   u   s    h        ≤        ≤    t  ,   a    5   e  ,   n   e   n    i   n    I    i   s    0   m  .   a   m   m   –   e  c    U    U   m   g  y    2  ,   u   a  n    0   m    t    l   a   –    i   n   o   n   v   I    i    1  ,   m    l   y  .    %    0    t   p  e    %    0   :   p  g   e   n   u   u  n    5    1   r   s   a   r    1    ±   a   o    ±   y    C   c   c   s   i   s   n   h   e   c   s   a    i   a   t   g   n   s    t   o    f   a   e   a   n   m    t   o   u    l    i    l   c   q   o   y   e   g   v   e    b   u   r   e    i   n    l    d    f   c   a   n    k    d   e    d   v   e    t   e   a    t   a   r   t   a   e   r    t   m  ,   u   a   n   r   r   p   o    i   w   o   i   n    f   m   r   p   r   e    U   p    d    D  e   n   n    M  p   o   a    P  p   u    i    t   x   a    d   c   a   c   n   m   r   n   u    U   o  a   e    f    f   e   g   r   e   a   u    t   o    l   n    f    i    d   e   l    l   o    f    t   s   e    t   a   v   v   e    d   e   t   y   u    l   s   u    l   p   p   a   n   e   p   n   v   a    i   c   r   u   a    d   r   r   s   e   e   s   e   r    t    t   r    t    i   w   e    i   u   o    t   m   w    l   m    i   c   r   a    l    t   o   p   y   e    f   a   c   p   u   e   y   s   t   r   n   n   s   e   e   a   e    h   a    h  a    i    l   e    i   u    T    M    T    l   x   q   u   e   r    A    F   a    b   c   n

   f   o    D    M  e   c    P  n   r   a   o  m    f   r  a   n   f   o   C   o   r    i    t   e  s   a  p  s    i   a   r   n   l   a  o  c   v   i    f   t   o  c   n   s  u    t    i   f   m    i    L

  n

BS EN 61557-12:2008

BS EN 61557-12:2008

 – 42 – 

4.7.10 Transients overvoltage (U tr ) measurements 4.7.10.1

Techniques

See Annex A of IEC 61000-4-30. Zero blind measurement is required. Reference waveform: 1,2/50 µs as defined in IEC 61000-4-5 4.7.10.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the rated ranges given in Table 32. 4.7.10.3

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 32: Table 32 – Intrinsic uncertainty table for transient overvoltage measurement Specified measuring range for PMD of function performance class C 

0 to U tr

a

Intrinsic uncertainty limits for PMD

Resolution for duration measurement  b

±3,0 % x U tr 

5 µs

a

The recommended values for the specified measuring range are 6 kV – 4 kV – 2,5 kV – 1,5 kV – 0,8 kV.

b

Duration measurement is optional. If it is provided, it shall be made at 50 % of the peak value of the transient.

4.7.11 Voltage interruption (U in t) measurements 4.7.11.1

Techniques

See  Annex A. Zero blind measurement is required. Subclause 5.4 of IEC 61000-4-30 applies excepted that, in this part, a synchronisation on zero crossing of voltage fundamental is not required. NOTE

This measurement is p ossible only if the neutral wire is connected to the PMD.

4.7.11.2

Rated range of operation

The manufacturer shall choose at least one value for the threshold of voltage interruption detection included in the range 1 % to 5 % of U n. Minimum detectable duration shall be equal at least to one period of the measured voltage. 4.7.11.3

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 33:

BS EN 61557-12:2008

 – 43 – 

Table 33 – Intrinsic uncertainty table for voltage interruption measurement Intrinsic uncertainty limits for PMD of function performance class C  a b

Specified measuring range Interruptions from 0 % to 5 % of U n

±1,0

Interruption duration a

× C 

Unit %U n

Less than two periods at the network frequency

ms c

The permitted values for function performance class C   are: 0,1 – 0,2 – 0,5 – 1 – 2.

b   The

permitted values and formula to calculate the system performance class of a PMD with an external voltage sensor are given in  Ann ex D.

c  This

is a fixed uncertainty.

4.7.12 Voltage unbalance (U nb , U nba ) measurements 4.7.12.1

Techniques

Zero blind measurement is not required.  According to manufacturer specifica tion, one of the f ollowin g funct ion s shall be implemented:

• •

amplitude voltage unbalance (U nba ): see  Annex A amplitude and phase voltage unbalance (U nb ): see IEC 61000-4-30

4.7.12.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the following rated range:  –

between 80 % and 120 % of U n

4.7.12.3

Intrinsic uncertainty table

The intrinsic uncertainty under reference conditions shall not exceed limits given in Table 34: Table 34 – Intrinsic uncertainty table for voltage unbalance measurement Intrinsic uncertainty limits for PMD of function performance class

Indicated range of U nb  or U nb a

Resolution

Unit

±0,1

%

C  a

0 % to 10 %

±1

× C  b

a

The permitted values for function performance class C   are: 0,2 – 0,5 – 1.

b

The diagram below shows an example of uncertainty limits for class 0,5: Intrinsic uncertainty limits for PMD offunctionperformanceclass0,5

0%

1%

2%

3%

4%

Truevalue

4,5%

5,5% 5%

6%

7%

8%

9%

10%

BS EN 61557-12:2008

 – 44 – 

4.7.13 Voltage harmonics (U h ) and voltage THD ( THD u  and THD-R u ) measurements 4.7.13.1

Techniques

Manufacturer shall specify sampling frequency, number of ranks, windows and filtering methods, aggregation method. NOTE 1

IEC 61000-4-7 compliance is not mandatory.

Zero blind measurement is not required. NOTE 2 When zero blind measurement is not implement ed, only stationar y and quasi-stat ionary harmonics can be measured.

4.7.13.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the rate d range given in Table 35: Table 35 – Rated range of operation for voltage harmonics measurement

4.7.13.3

PMD types

Minimum bandwidth

Fundamental frequency range

PMD

15 times rated frequenc y

45 Hz to 65 Hz

Intrinsic uncertainty table

The uncertainty indicated in Table 36  and Table 37  applies for a single tone stationary harmonic signal over the whole working conditions. Table 36 – Intrinsic uncertainty table for voltage harmonics measurement

Specified measuring range U h  > 3

× U n × C  / 100

≤  3

× U n × C / 100

U h

Intrinsic uncertainty limits for PMD of function performance class C  a b

Unit

±5,0

%U h

±0,15

× C 

%U n

a

The permitted values for function performance class C   are: 1 – 2 – 5.

b

The permitted values and formula to calculate the system performance class of a PMD with an external voltage sensor are given in  Ann ex D.

Table 37 – Intrinsic uncertainty table for voltage THD u  o r THD-R u  measurement Specified measuring range for voltage THD 0 % to 20 %

Intrinsic uncertainty limits for PMD of function performance class C  a b ±0,3

×C

c

Unit point c

a

The permitted values for function performance class C   are: 1 – 2 – 5.

b

The permitted values and formula to calculate the system performance class of a PMD with an external voltage sensor are given in  Ann ex D.

c

0,3 x C   is a constant uncertainty. For example with 10 % of THD, if C   = 1, the m easured value may be between 9,7 and 10,3.

BS EN 61557-12:2008

 – 45 – 

4.7.14 Current harmonics (I h ) and current THD ( THD i  and THD-R i ) measurements 4.7.14.1

Techniques

 According to manuf acturer specification : samplin g frequenc y, num ber of ranks, win dows and filtering methods, aggregation method. Zero blind measurement is not required. NOTE When zero blind measurement is not implemented, only stationary and quasi-stationary harmonics can be measured.

4.7.14.2

Rated range of operation

The intrinsic uncertainty requirements shall apply within the rate d range given in Table 38: Table 38 – Rated range of operation for current harmonics measurement

4.7.14.3

PMD types

Minimum bandwidth

Fundamental frequency range

PMD

15 times rated frequenc y

45 Hz to 65 Hz

Intrinsic uncertainty table

The uncertainty indicated in Table 39 and Table 40 apply for a single tone stationary harmonic signal over the whole working condition. Table 39 – Intrinsic uncertainty table for current harmonics measurement

PMD types PMD-Sx

PMD-Dx

a b

Specified measuring range I h > 10

× I n × C  / 100

I h ≤  1 0

× I n × C / 100

I h > 10

× I b × C  / 100

I h ≤  1 0

× I b × C / 100

Intrinsic uncertainty limits for PMD of function performance class C  a b

Unit

±5,0

%I h

±0,5

× C 

±5,0 ±0,5

× C 

%I n %I h %I b

The permitted values for function performance class C   are: 1 – 2 – 5. The permitted values and formula to calculate the system performance class of a PMD with an external current sensor are given in  Ann ex D.

BS EN 61557-12:2008

 – 46 – 

Table 40 – Intrinsic uncertainty table for current THD i  and THD-R i  measurement Specified measuring range

Intrinsic uncertainty limits for PMD of function performance class C  a b

0 % to 100 % 100 % to 200 %

±0,3 ±0,3

× C 

point  c

c

× C  × THD  / 100

Unit

d

point  c

a

The permitted values for function performance class C   are: 1 – 2 – 5.

b

The permitted values and formula to calculate the system performance class of a PMD with an external current sensor are given in  Ann ex D.

c

0,3 x C   is an absolute uncertainty. For example with 10 % of THD, if C   = 1, the measured value may be between 9,7 and 10,3.

d

THD  is the measured value of current THD expressed in %.

4.7.15 Minimum, maximum, peak, three-phases average and demand measurements 4.7.15.1

Rated range of operation

Manufacturer shall specify rated range of operation. 4.7.15.2

Intrinsic uncertainty table

Uncertainty on these values (minimum, maximum, …) shall be the same as those from the corresponding measurements used to calculate these values. For instance, a PMD claiming a class C   performance on power measurement shall have to comply with the same performance class C   for the power demand measurement if any. Calculation methods are specified in  Annex B. 4.8

Requirements for PMD-A functions

Measuring uncertainties, measuring methods, measuring ranges, testing methods shall comply with IEC 61000-4-30 class A, and the complementary characteristics given in Table 41 below. Depending on the purpose of the measurement, all or a subset of the functions listed in Table 41 shall be measured. NOTE

For contractual applications, all functions listed in Table 41 may be necessary.

 An y "powe r quality assessment functio n" of a PMD-A shall comply wit h the measurement methods and measurement uncertainty defined for class A in IEC 61000-4-30. Each function shall comply with IEC 61000-4-30 within operating conditions specified in 4.5.2 of this standard.

 – 47 – 

BS EN 61557-12:2008

For PMD-A, the maximum variation caused by change of ambient temperature within the specified temperature operating range according to 4.5  shall not exceed 1,0 x measuring uncertainty as specified in IEC 61000-4-30. Manufacturer s shall specify the variation as required in Note 2, subclause 4.1 of IEC 61000-4-30. Table 41 – Complementary characteristics of PMD-A Function Other complementary characteris tics f

Range of operation: 50 % U din to U max or 1 % U din to U max if dips and swells are in concern. See Note.

U

No complementary characteristics.

P st , P lt

No complementary characteristics.

U di p

Threshold settable from 50 % to 120 % of U di n; Hysteresis: 2 % of U di n

U swl

Threshold settable from 50 % to 120 % of U di n; Hysteresis: 2 % of U di n

U int

Threshold settable from 0,5 % to 10 % of U di n; Duration measurement uncertainty < 2 c ycles

U nb

Limit settable from 0 % to 5 %; Resolution: 0,05 % minimum

U h

Requirement is to measure up to 50th  rank, consequently minimum frequency bandwidth shall be at least 51 times the rated frequency.

I h

No complementary characteristics.

Msv 

Threshold settable from 0,1 % to 10 % of U di n

NOTE Between 1% of U di n  and 50% of U di n, PMD using frequency detection circuits can measure voltage with the last consistent measured value of frequency.

4.9

General mechanical requirements

4.9.1 Vibration requirements Requirements for portable equipment are described in IEC 61557-1. For fixed installed equipment the requirement is as below:  –

ampli tude: 0,35 mm ;

 –

frequency: 25 Hz;

 –

dur ation: 20 min in each 3 directions;

 –

PMD under test must be power ed on.

The PMD functions shall remain in their specifications during the test. 4.9.2 IP requirements Manufacturer s hall d ocument e quipment IP according t o IEC 60529. The minimum requirements are given in Table 42, which specifies minimum IP requirements for the different kind of housings of PMD:

BS EN 61557-12:2008

 – 48 – 

Table 42 – Minimum IP requirements for PMD Kind of PMD Fixed installed PMD   panel

Front panel

Housing, except front panel

IP 40

IP 2X

IP 40

IP 2X

IP 2X

IP 2X

IP 40

IP 40

mounted devices.

Fixed installed PMD   modular

devices snapped on DIN rails within distribution panel. Fixed installed PMD   housing

devices snapped on DIN rails within distribution panel. Portable PMD

4.10

Safety requirements

PMD shall com ply with s afety requirements requirements of the following subclauses.

of IEC 61010, and in addition with the

NOTE 1

Class II requirement as stated in IEC 61557-1 is not mandatory.

NOTE 2

Protection classes are defined in IEC 61140.

4.10.1 Clearances and creepage distances Clearances and creepage distances shall be selected at least in accordance with:  –

pollution degree 2;

 –

measu rement category III f or measuring input c irc uits;

 –

ove rvoltage categor y I II for mains circuits.

NOTE 1

Measurement category is defined in IEC 61010-2-030.

NOTE 2 For portable equipment, overvoltage category II is acceptable only for mains circuits powered from socket outlets.

4.10.2 Connection of a fixed installed PMD with a current transformer When a hazardous situation can be the result of an unintended disconnection of a current transformer from its PMD, connections of the current inputs shall be designed in such a way to prevent open circuit condition. This condition may be achieved either by removable auto short-circuiting connectors or screwable connectors or fixed connections or external protective devices, or protective devices integrated in the current transformer. 4.10.3 Connection of a PMD with a high voltage sensor The connection of a PMD xS or a PMD xD with external high voltage sensors (e.g. for systems with rated voltages higher than 1 000 V a.c. and 1 500 V d.c.) is allowed, provided that design features of such sensors prevent any hazards. 4.10.4 Accessible parts Requirements for accessible parts as defined in IEC 61010 apply.

 – 49 – 

BS EN 61557-12:2008

Circuits intended to be connected to an external accessible circuit shall be considered as accessible conductive parts, e.g. communication circuits.  A communica tion port that ma y be connect ed to a data system sha ll als o be conside re d as an accessible conductive part. These accessible conductive parts require protection against single fault condition. NOTE Basic insulation is not a sufficient protection against single fault condition. Examples of relevant insulation is double insulation or reinforced insulation, etc., see IEC 61010.

4.10.5 Hazardous live parts In a distribution system, neutral conductor shall be considered as a hazardous live part. 4.11

Analog outputs

4.11.1 General requirements The global uncertainty of each analogue output representing a measured parameter shall be in the uncertainty limits specified for the measurement of that parameter in Clause 4 unless otherwise specified. NOTE 1 For testing of analog outputs, see 6.1.11. For a PMD fitted with analog outputs the requirements specified in 4.11.5 shall apply. NOTE 2

The current analog output signal should be 4 mA to 20 mA, but 0 mA to 20 mA is also possible.

NOTE 3 The preferred volt age output sign al is 0 V to 10 V. Voltages 0 V to ±1 V and 0 V to -10 V are also possible.

4.11.2 Compliance voltage Current output signals shall have a compliance voltage of at least 10 V. The actual compliance voltage shall be specified in the accompanying documentation (see 5.2). When tested in accordance with the compliance voltage tests of 6.1.11.2  the uncertainty of the analog output shall not exceed (2 × C ) % of full scale for a PMD with an analog output of performance class C . 4.11.3 Analog output ripple content When tested in accordance with 6.1.11.3 the maximum ripple content in the output signal for an output of performance class C   shall not exceed (2  × C ) % of full scale of the maximum specified output signal. 4.11.4 Analog output response time The response time of the analog output, in accordance with 6.1.11.4, for both increasing and decreasing inputs if different, shall be specified in the accompanying documentation (see 5.2). 4.11.5 Limiting value of the analog output signal The output signal shall be limited to a maximum of twice the rated maximum output signal. For bipolar outputs, this shall apply in both directions.

BS EN 61557-12:2008

 – 50 – 

When tested in accordance with 6.1.11.5 when the measurement is not between the lower and upper values represented by the maximum and minimum output signals, the meter shall not, under any conditions of operation except loss of auxiliary power, produce an output having a value between its maximum and minimum output signals. 4.11.6 Pulse outputs For those outputs, subclause 4.1 of IEC 62053-31 (functional requirements) shall apply.

5

Marking and operating instructions

Marking and operating instructions shall comply with IEC 61010 and IEC 61557-1, unless otherwise specified in this standard. 5.1

Marking

Marking requirements as defined in IEC 61010 shall apply. In addition, but not in contradiction, the following markings shall be clearly readable and indelible:  –

wir ing diagrams or Sym bol 14 according to IEC 61010-1;

 –

if nec ess ar y, als o inside the devic e, serial number, year of manufacturing or typ e designation.

5.2

Operating and installation instructions

Operating instructions defined in IEC 61010 shall apply. In addition, but not in contradiction, the following requirements apply: 5.2.1 General characteristics The following characteristics shall be documented:  –

calibration per iod, if a calibration is nec essary;

 –

the r ated voltage in one of the followi ng forms:  –

the number of active conductor s of the connecting system if more than one, and the applicable voltage at the PMD terminals of the voltage circuit(s);

 –

the nominal voltage of the system or the se con dar y volta ge of the ins trument transformer to which the PMD is intended to be connected;

 –

for direct connect ed PMD, the basic current (I b) and the maximum current (I ma x) expressed. For example: 10-40 A or 10(40) A for a PMD having a basic current of 10 A and a maximum current of 40 A;

 –

for current trans former-operated PMD, the rated secondary current (I n) of the transformer(s) and the maximum secondary current ( I ma x) of the transformer which the PMD should be connected to. For example: /5 (6,5) A.

 –

for sensor- operated PMD, the main characteris tics of the corr esponding PMD input. For example: 1 V / 1 000 A;

 –

the r ated fr equency o r frequency r ange in Hz;

 –

for energy measurement , the meter constant if any;

 –

start-up tim e, if it is longer tha n 15 s.

BS EN 61557-12:2008

 – 51 – 

5.2.2 Essential characteristics 5.2.2.1

Characteristics of PMD

Characteristics of the PMD shall be specified in a table as specified in Table 43  with the following items: a) power quality assessment function (if any); b) classification of PMD according to 4.3; c) temperature according to 4.5.2.1 and 4.5.2.2; d) humidity and altitude conditions according to 4.5.2.3; e) active power or active energy function (if existing) performance class according to 4.7.1. The sequence of function symbols shall be the following: Table 43 – PMD specification form Type of characteristic

NOTE

Examples of possible characteristic value

Power quality assessment function (if any)

-A or blank

Classification of PMD according to 4.3

SD or DS or DD or SS

Temperature

K40 or K55 or K70 or Kx

Humidity + altitude

Blank or extended values

 Act ive pow er or act ive energy function (if function available) performance class

0,1 or 0,2 or 0,5 or 1 or 2

Other complementary characteristics

It is strongly recommended that all items be listed, and only e xisting ones be specified.

5.2.2.2

Characteristics of functions

Characteristics of functions of the PMD shall be specified in a table as specified in Table 44 with the following items: a) function symbols as defined in Table 44; b) function performance class according to this standard; c) measuring range for the specified performance class; d) other complementary characteristics. The sequence of function symbols shall be the following:

BS EN 61557-12:2008

 – 52 – 

Table 44 – Characteristics specification template function symbols

Function performance class according to IEC 61557-12

Measuring range

Other complementary characteristics

P  Q A, Q V S A, S V E a E rA , E rV E apA , E apV f  I  I N , I Nc U  PF A, PF V P st , P lt U dip U swl U tr  U int U nba U nb U h THD u THD-R u I h THD i THD-R i Msv

NOTE

It is strongly recommended that all functions be listed, and only existing ones be specified.

5.2.2.3

Characteristics of "Power quality assessment functions"

Characteristics of the "power quality assessment functions" of the PMD shall be specified in a table as specified in Table 45 with the following items: a) function symbols as defined in Table 45; b) function performance class according to this standard; c) measuring range for the specified performance class; d) other complementary characteristics; e) measurement method class according to IEC 61000-4-30. The sequence of function symbols shall be the following:

BS EN 61557-12:2008

 – 53 – 

Table 45 – Characteristics specification template function symbols

Function performance class according to IEC 61557-12

Measuring range

Other complementary characteristics

Class acc. to IEC 61000-4-30 if any

f  I  I N , I Nc U  P st , P lt U dip U swl U int U nba U nb U h I h Msv 

NOTE

It is strongly recommended that all functions be listed, and only existing ones be specified.

5.2.3 Safety characteristics 5.2.3.1

Insulation between circuits

For safety reasons, accessible parts shall be defined and documented. Manufacturer shall state t he type of insulation accordin g to IEC 61010 used between each independent circuit (e.g. basic insulation, double or reinforced insulation, etc. )

6

Tests

Measuring equipment shall be tested in accordance with IEC 61557-1 unless otherwise specified.  Al l tests shall be carr ied out under reference con dit ions unles s otherwise specified. Th e reference conditions are stated in 4.5.1 of this standard. 6.1

Type tests of PMD

Type tests shall be executed to check the compliance with the requirements of 4.7, 4.6 and 4.5. For some of them, tests of the influence quantities on several functions can be combined if applicable (e.g. test of influence of temperature done on active power measurement can be done at the same time as those of voltage and current).

BS EN 61557-12:2008

 – 54 – 

6.1.1 Test of temperature influence The temperature coefficient shall be determined for the whole operating range. The operating temperature range shall be divided into 20 K wide ranges. The temperature coefficient shall then be determined for each of these ranges, by taking measurements 10 K above and 10 K below the middle of the range. During the test, the temperature shall be in no case outside the specified operating temperature range. The indicated temperature coefficient shall be the greatest one. 6.1.2 Active power 6.1.2.1

Influence of harmonics in current and voltage circuits

Test conditions shall be:  –

fundamental frequenc y current: I 1 = 50 % of I ma x;

 –

fundamental frequenc y voltage: U 1 = U n ;

 –

fundamental frequenc y p ower factor: 1;

 –

content of 5 th  harmonic voltage: U 5 = 10 % of U n;

 –  –

content of 5 th  harmonic current: I 5 = 40 % of I 1 ; har mo nic power factor: 1;

 –

fundamental and harmonic volta ges are in phase, at positive zero crossing;

 –

the total act ive power is 1,04

6.1.2.2

× P 1 = 1,04 × U 1 × I 1 .

Influence of odd harmonics in the current circuit

The peak value of the test waveform shall be equal to

√ 2 × I b or to √ 2 × I n.

The following current test waveform shall be generated: Test waveform 1 Rise time 200 µs ± 100 µs Start 5 ms ± 0,1 ms   e    d   u    t    i    l   p   m   a   e   v    i    t   a    l   e    R

0,5

0

 –0,5 Reference waveform: I rms = 0,5 I b or 0,5 I n  –1 0

2

4

6

8

10 12 Time (ms)

14

16

18

20 IEC 1275/07

Figure 4 – Waveform for odd harmonics influence test on active power measurement

BS EN 61557-12:2008

 – 55 – 

Harmonic content 70

60    ) 50    %    (   e    d   u    t    i    l 40   p   m   a   c    i   n 30   o   m   r   a    H

20

10

0 0 50

250

500

750

1 000 1 250 1 500 Frequency (Hz)

1 750

2 000

2 250

2 500 IEC 1276/07

Figure 5 – Spectral content for odd harmonics influence test on active power measurement NOTE 1

The reference waveform and the distorted waveform result in the same active power or active energy.

NOTE 2 The curve, diagram and values are given at 50 Hz. For other frequencies, they must be adapted accordingly.

6.1.2.3

Influence of sub-harmonics

The peak value shall be equal to √ 2 × I b   or to waves followed by 2 non-signal periods. The following test waveform shall be generated:

√ 2 × I n. Cycle of the signal is made of 2 full

BS EN 61557-12:2008

 – 56 – 

Test waveform 1 Reference waveforme: I rms = 0,5 I b or 0,5 I n   e 0,5    d   u    t    i    l   p   m   a   e 0   v    i    t   a    l   e    R

 –0,5

 –1 0

10

20

30

40 Time (ms)

50

60

70

80 IEC 1277/07

Figure 6 – Waveform for sub-harmonics influence test on active power measurement Spectral content 50 45 40    )    %    (   e    d   u    t    i    l   p   m    A

35 30 25 20 15 10 5 0 0 12,5

37,5 50 62,5

87,5

112,5

137,5

162,5

187,5

212,5

237,5

2 62,5

Frequency (Hz)

2 87,5 IEC 1278/07

Figure 7 – Spectral content for sub-harmonics influence test on active power measurement NOTE 1

The reference results in the same active power or active energy.

NOTE 2 The curve, diagram and values are given at 50 Hz. For other frequencies, they must be adapted accordingly.

 – 57 – 

6.1.3

BS EN 61557-12:2008

Apparent power

Test on apparent power is not mandatory if two at least of the following functions are tested:  –

act ive power ;

 –

reactive power ;

 –

power factor.

6.1.4 Power factor Test on power factor is not mandatory if two at least of the following functions are tested:  –

act ive power ;

 –

reactive power ;

 –

apparent power .

6.1.5 Common mode voltage rejection test For each isolated current input, the following test (as described in Figure 8) shall be made. It consists in calculating the difference between two measurements, P1 without common mode voltage and P2 with a common mode voltage applied between the current inputs and the reference ground.

Current generator: 10 %I b for PMD DD 5 % I n for PMD SD

Current Input

Power factor = 1 between current and voltage  Active power measurement (display, or any output)

Common mode voltage generator at f n

U n

P 1 without common  mode voltage then P 2 with common mode voltage

Voltage Input

Common mode voltage rejection = (P 1 – P 2) / P 1

Reference ground

 A conductive foil shall be connected to earth in case of equipment whose enclosure is not connected to ground IEC

Figure 8 – Common mode voltage influence testing

1279/07

BS EN 61557-12:2008

 – 58 – 

6.1.6 Frequency With the set-up of Table 17, the following waveform is generated: Test waveform

150

100   e    d   u 50    t    i    l   p   m   a   e 0   v    i    t   a    l   e    R

 –50

 –100

 –150 0

2

4

6

8

10

12

14

16

Time (ms)

18

20

IEC 1280/07

Figure 9 – Waveform for harmonics influence test on frequency measurement NOTE 1

The relative amplitude is expressed in % of fundamental peak value.

NOTE 2

The curve is given at 50 Hz. For other frequencies, it must be adapted accordingly.

6.1.7 Measurement of voltage harmonics The following tests shall be performed at rated voltage U n   at 45 Hz, 50 Hz and 55 Hz for 50 Hz rated frequency, and at 55 Hz, 60 Hz and 65 Hz for 60 Hz rated frequency. 6.1.7.1

Test with a sinusoidal waveform

Test shall be performed with a pure sinusoidal voltage waveform, with frequencies taken from 6.1.7. PMD shall not measure any voltage harmonics component with amplitude above 0,0015 × C  × U n  (C   is the function performance class). 6.1.7.2

Test with a square waveform

Test shall be performed with a square voltage waveform with frequencies taken from 6.1.7. PMD shall measure the voltage harmonics components within the uncertainty limits defined in Table 36. The spectral content of the square waveform shall include at least the upper limit of the bandwidth specified in 4.7.13 without alteration. 6.1.8 Measurement of current harmonics The following tests shall be performed at rated current I n  o r I b and at 45 Hz, 50 Hz and 55 Hz for 50 Hz rated frequency, and at 55 Hz, 60 Hz and 65 Hz for 60 Hz rated frequency.

 – 59 – 

6.1.8.1

BS EN 61557-12:2008

Test with a sinusoidal waveform

Test shall be performed with a pure sinusoidal current waveform, with frequencies taken from 6.1.8. PMD shall not measure any current harmonics component with amplitude above 0,005 × C  x I n (or I b). (C   is the function performance class). 6.1.8.2

Test with a square waveform

Test shall be performed with a square current waveform with frequencies taken from 6.1.8. PMD shall measure the current harmonics components within the uncertainty limits defined in Table 39. The spectral content of the square waveform shall include at least the upper limit of the bandwidth specified in 4.7.14 without alteration. 6.1.9 Dips and swells Tests shall at least be done with rectangular dip or swell modulation and with a dip or swell duration of one full cycle. Test of the influence quantities can be omitted if this test has been done during the voltage r.m.s. measurements. 6.1.10 Voltage interruptions Tests shall at least be done for a voltage interruption of one full cycle. 6.1.11 Outputs tests 6.1.11.1

General

PMD shall be tested under reference conditions. 6.1.11.2

Test of compliance voltage and effect of variation of load.

This test shall only be carried out on PMD with analogue outputs that are a current signal. Testing shall be carried at the minimum and maximum (low and high) values of the analogue output. At each point the output load resistance shall be set at 10 % and 90 % of its specified maximum value:  –

the supply voltage for the analogue output, if supplie d from a source external to the PMD, shall be set to its minimum and maximum specified values;

 –

the supply of the PMD sha ll be set to its specified minim um and maximum values or in accordance with the rated voltage ±15%.

The worst case maximum and minimum readings at the low and high outputs shall be noted. The percentage uncertainty E   shall be determined using the following equation:

E =

N − W  × 100 U 

where N  is the rated signal, W  is the worst case signal and U  is the output span.

BS EN 61557-12:2008

6.1.11.3

 – 60 – 

Test of ripple content

The ripple content of the analogue output shall be tested at rated minimum and maximum values of the output. The ripple content shall be measured as a peak-to-peak value. 6.1.11.4

Tests of analogue output response time

The response time for an increasing input shall be determined for an input step intended to produce a change in output signal from 0 % to 100 % of the output range as the time for the output to reach 90 % of the output range. The response time for a decreasing input shall be determined for an input step intended to produce a change in output signal from 100 % to 0 % of the output range as the time for the output to reach 10 % of the output range. 6.1.11.5

Test of limit value of analogue output

The limiting value of the analogue output shall be tested by varying the input parameter between minimum and maximum values. Any programmable features of the output, such as input offset or full-scale value, shall be set so as to provide the maximum overloads. 6.1.12 Climatic tests

 Aft er an appr opriat e rec overing tim e aft er each climatic tes t, the PMD shall show no damage or change of the information and shall operate within its specifications. 6.1.12.1

Dry heat test

The test shall be carried out according to IEC 60068-2-2, under the following conditions:  – P MD in non-operating condit ion;  – t emperature:

+70 °C ±2 °C for K40 PMD and K55 PMD, +85 °C ±2 °C for K70 PMD;

 – duratio n of tes t: 6.1.12.2

16 h.

Cold test

The test shall be carried out according to IEC 60068-2-1, under the following conditions:  –

PMD in non-operating condition;

 –

temperature:

–25 °C ±3 °C for K40 PMD and K55 PMD ,  –40 °C ±3 °C for K70 PMD;

 –

durati on of tes t:

6.1.12.3

16 h.

Damp heat cyclic test

The test shall be carried out according to IEC 60068-2-30, under the following conditions:  –

voltage and auxiliar y c irc uits energised wit h rate d v olt age;

 –

wit hout any cur rent in the current cir cuits ;

 –

var iant 1;

 –

upper temperature:

+40 °C ±2 °C for K40 PMD, +55 °C ±2 °C for K55 PMD, +70 °C ±2 °C for K70 PMD;

 – 61 – 

BS EN 61557-12:2008

 –

no special precautions shall be tak en regarding t he rem oval of surface moisture;

 –

durati on of the test: 6 c ycl es.

The damp heat test also serves as a corrosion test. The result is judged visually. No trace of corrosion likely to affect the functional properties of the PMD s hall be apparent. 6.1.13 EMC tests

The PMD shall be tested in accordance with IEC 61326-1 Table 2 (industrial location). For EM RF field and conducted RF the following requirements apply:  –

auxiliar y circ uits of PMD shall be energised with the rat ed vol tage;

 –

PMD shall be tes ted in their operat ing con dit ions wit h basic current I b , respectively rated current I n , rated voltage, power factor equal to 1 (or equal to 0 for reactive power) whichever is applicable.

Variations due to the EM influence quantities as defined in the previous tables (Limits of variation due to influence quantities) apply. 6.1.14 Start up tests

Starting time of PMD without communication or local user interface shall be tested with the following procedure:  – configure P MD scales to max imum poss ible values wit hout c aus ing calculation overflows;  – set up kW h/pu lse v alue t o the minimum possible value;  – set up optical pick up probe or other pulse pic k-up device; a solid state relay or a mechanical relay may be used as the energy pulse output device;  –

power down the PMD;

 –

apply U ma x and I ma x, PF=1,0 on all voltage and current measurement inputs;

 – power up the PMD and measur e tim e from the applicat ion of power until the first ener gy pulse registered by the probe. 6.2

Type tests of PMD-A

Tests shall be done according to Clause 6 of IEC 61000-4-30 and if necessary according to this standard. 6.3

Routine tests

6.3.1 Protective bonding test

PMD shall be tested in accordance with Annex F of IEC 61010-1.

BS EN 61557-12:2008

 – 62 – 

6.3.2 Dielectric strength test

PMD shall be tested in accordance with Annex F of IEC 61010-1. 6.3.3 Uncertainty test

Every basic measurement function (e.g. current, voltage, power, etc.), which is accessible to the user, shall be submitted to a routine test. NOTE

It is strongly recommended that the results of this test should be recorded.

BS EN 61557-12:2008

 – 63 – 

Annex A (informative) Definitions of electrical parameters

This informative annex gives the preferred definition and method for calculating quantities. Manufacturers using other methods will have to specify their own method in technical documentation. This informative annex cannot be considered as a requirement for PMD-A. See definitions for PMD-A in this standard which refer only to IEC 61000-4-30 concerning measuring aspects. Table A.1  gives the list of symbols used in this annex. Table A.2  specifies how to calculate par ameters. Table A.1 – Symbols definition Symbol

Definition

U resid N

Total number of samples by period (period 20 ms for instance)

k

Number of sample in the period (0

 p

Number of phase ( p = 1, 2 or 3; or  p = a, b, c; or  p = r, s, t; or  p = R, Y, B) a

g

Number of phase (g = 1, 2 or 3; or g   = a, b, c; or g   = r, s, t; or g   = R, Y, B) a

i p k  

Phase p current sampling number k 

v pN k  

Phase p to Neutral voltage sampling number k 

v gN k  

Phase g  to Neutral voltage sampling number k 

ϕ p h i  a  p an d g  are

Residual voltage

≤ k  < N )

Phase angle between current and voltage for phase p, see Figure A.2 Harmonic component of rank i  variable meaning a number of phase.

BS EN 61557-12:2008

 – 64 – 

Table A.2 – Calculation definitions of electrical parameters, for 3 phase unbalanced system with neutral

These methods are derived from IEEE Std 1459-2000: Item

Definition

R.m.s current for phase  p

N −1

Not relevant method

2

∑ i pk 

k =0

I p =

N 

R.m.s neutral current

N −1

∑ (i 1k  + i 2k  + i 3 k )

2

Vectorial sum of phase currents.

2

Vectorial difference of line L voltage and neutral

k = 0

I N =

N 

Lp-N r.m.s. voltage

N −1

2

∑ v pNk 

k = 0

V pN =

N 

Lp -Lg r.m.s. voltage

N −1

∑ (v gNk  − v pNk )

U pg =  Act ive pow er for pha se  p

voltage:

k = 0

N  N −1 1 ⋅ ∑ (v pNk  × i p k ) N  k  0 =

P p

=

 App are nt pow er fo r p has e p

Sp

= V pN × I p

Sign of reactive power (SignQ)

SignQ(ϕ p ) = +1 if ϕ p ∈ [0° − 180°]

a

SignQ(ϕ p ) = −1 if  ϕ p ∈ [180° − 360°] Reactive power for phase p

Qp

= SignQ(ϕ p ) × Sp2 − P p 2

Total active power

P  = P 1 + P 2 + P 3

Total reactive power (vector)

QV

= Q1 + Q 2 + Q3

SV

= P 2 + QV 2

S A

= S1 + S 2 + S3

Q A

= S A 2 − P 2

Total apparent power (vector)

Total apparent power (arithmetic) Total reactive power (arithmetic) b

Power factor (vector)

PF V

=

P  SV

PF   A

=

P  S A

Power factor (arithmetic)

b

a

U pg = V pN − V gN

BS EN 61557-12:2008

 – 65 – 

Table A.2 (continued) Item

Definition

Voltage dips

Voltage swells

U dip (%) =

U n − U resid U n

U swl (%) =

U resid − U n U n

 Am pli tud e v ol tag e unb ala nce

U nba = U avg =

max U 12

Not relevant method

− U avg , U 23 − U avg , U 31 − U avg U avg

where

U 12 + U 23 + U 31 3

Total Harmonic Distortion referring to r.m.s. value

2

∑ hi THD − R (%) =

(THD-R u for voltage and THD-R i for current).

i= 2

rms value

r.m.s. value = U rms  for THD-R u I rms  for THD -R i total harmonic distortion referring to fundamental

2

∑ hi THD(%) =

(THD u for voltage and THD i  for current). a

i=2

h1

See Figure A.2.

b  This

power is unsigned.

Sv

Sc

Qc

P c Sb P b

Qb

Sa Qa P a Sv S A IEC 1281/07

Figure A.1 – Arithmetic and vector apparent powers in sinusoidal situation

BS EN 61557-12:2008

 – 66 – 

Export active power 

Import active power 

 –

+ II

Import reactive power  Export reactive power 

I

S

+ Q

ϕ 

P

I 

 –

III

IV

IEC

NOTE 1

Diagram in accordance with clauses 12 and 14 of IEC 60375.

NOTE 2

Reference of this diagram is the current vector (fixed on right-hand line).

NOTE 3

The voltage vector V  varies its direction according to the phase angle

NOTE 4 The phase angle (counter clockwise)

1282/07

ϕ.

ϕ  between voltage V   and current I   is taken to be positive in the mathematical sense

Figure A.2 – Geometric representation of active and reactive power

 – 67 – 

BS EN 61557-12:2008

Annex B (normative) Definitions of minimum, maximum, peak and demand values

B.1

Demand quantities

 A d emand is the average val ue of a q uantity over a s pecified period of time. B.1.1

Power demand

Power demand is calculated using arithmetical integration of power values during a period of time divided by the length of the period. The result is equivalent to the energy accumulated during the period of time divided by the length of the period. B.1.2

Current demand

Current demand is calculated using arithmetical integration of the current r.m.s. values during a period of time, divided by the length of the period. B.1.3

Thermal current demand (or bi-metal current demand)

Thermal current demand calculates the demand based on a thermal response, which mimics the analog thermal demand meters as described in Figure B.1. Source input

Thermal demand

100 % Defined by time const setup register

0%

Interval

Defined by interval setup register

NOTE

Time

IEC 1283/07

n value usually is 90 %, time interval usually is 15 min.

Figure B.1 – Thermal current demand B.1.4

Specified intervals for demand calculation

The PMD handle the intervals duration to calculate the demand. PMD can implement several methods:

•

fixed block interval: the intervals are consecuti ve; the PMD calculates and updates the demand at the end of each interval;

BS EN 61557-12:2008

 – 68 – 

Demand value is the average for last completed interval

Calculation updates at the end of t he interval

15-minute interval

15

15-minute interval

30

15-minute

Time (min)

45

Fixed block IEC 1284/07

NOTE

•

15 min is only an example.

sliding block interval: the intervals are sliding; the PMD calculates and updates the demand at the sliding speed. Calculation updates 15-minute interval

Sliding block

Demand value is the average for last completed interval

Time (s)

IEC

NOTE

15 min is only an example.

B.2

Peak demand quantities

1285/07

Peak demand is the highest demand value (positive or negative) since the beginning of the measurement or the last reset.

B.3

Three-phases average quantities

In a three or four wire system, the average value of a quantity is the arithmetical average of each phase value: Example: 3-phase average line to neutral voltage = ( V1  r.m.s. voltage + V2   r.m.s. voltage + V3 r.m.s. voltage) / 3

B.4

Maximum and minimum quantities

The maximum value of a quantity is the highest value measured or calculated since the beginning of the measurement or the last reset. The minimum value of a quantity is the lowest value measured or calculated since the beginning of the measurement or the last reset.

 – 69 – 

BS EN 61557-12:2008

Annex C (informative) Intrinsic uncertainty, operating uncertainty, and overall system uncertainty

Figure C.1 below describes different kind of uncertainties:

Uncertainty and variations due to external sensors accuracy and to impedance of wires

Variations due to influence quantities

Overall system uncertainty according to IEC 61557-12 Uncertainty under reference conditions

Operating uncertainty according to IEC 61557-1 Measurement uncertainty according to IEC 61000-4-30

Intrinsic uncertainty IEC

1286/07

Figure C.1 – Different kind of uncertainties

C.1

Operating uncertainty

Operating uncertainty shall include intrinsic uncertainty (under reference conditions) and variation due to influence quantities. N 

Operating uncertainty = Intrinsic uncertainty

+ 1,15 ×

2

∑ (variation due to influence quantities) i =1

with N   = number of influence quantities.

C.2

Overall system uncertainty

Overall system uncertainty shall include operating uncertainty, uncertainty due to impedance of wires and uncertainty due to sensors. For PMD DD: Overall system uncertainty = operating uncertainty

BS EN 61557-12:2008

 – 70 – 

For PMD xS and PMD Sx: The formula given below is a simplified approach, and applies only to voltage, current, active power and active energy measurements:

Overall system uncertainty

2

N 

= 1,15 × (PMD operating uncertainty) + ∑ (sensoruncertainty + wirings uncertainty) 2 i =1

with N   = number of kind of external sensors (voltage or current). NOTE N   = 1 when only a current (or voltage) sensor is used, N = 2 when a current sensor and a voltage sensor are used.

BS EN 61557-12:2008

 – 71 – 

Annex D (informative) Recommended sensor classes for the different kinds of P MD

D.1

General considerations

The association of a PMD Sx, PMD xS or PMD SS with external current and/or voltage sensors builds a complete system. The system performance class depends on the sensor class and the PMD performance class (See Clauses D.2 and D.3 for evaluation of the s ystem performance class). However, this system performance class is only applicable for the range where the sensor intrinsic uncertainty is within the limit of its performance class, and is not equivalent to the performance class of a PMD DD. Current sensors that comply with IEC 60044-1 for example, have only a limited specified range compared to a PMD DD of the same performance class. Special considerations must be taken for power and energy measurements, because phase error of the sensor affects the measurements for non unity power factor: a phase error of 20 min adds 1 % error for active power measurement at PF = 0,5. For this reason, if improved performance class is required, it is strongly recommended to use class 0,2S or class 0,5S sensors for power or energy measurement.

D.2

PMD with external current sensor or voltage sensor

Table D.1 gives some recommendations when associating a PMD with an external sensor. Table D.1 – PMD SD associated to current sensor or PMD DS associated to voltage sensor Performance class of the PMD without external sensors

Recommended sensor class to associate to the PMD b c

Expected performance class for PMD-Sx or PMD-xS including their external sensors

maximum possible sensor class to associate to the PMD a

0,1

0,1 or below

0,2

0,2

0,2

0,2 or below

0,5

0,5

0,5

0,5 or below

1

1

1

1 or below

2

2

2

2 or below

5

5

5

5 or below

10

a

This induces an acceptable loss of performance of the system.

b

For power and energy measurements 0,2 S and 0,5 S class sensors are usually required.

c

Class sensor refers to classes defined in IEC 60044-1, IEC 60044-2, IEC 60044-7 and IEC 60044-8. When transducers replace sensors, class sensor refers to intrinsic uncertainty of the transducer.

BS EN 61557-12:2008

 – 72 – 

Overall system performanc e class = 1,15 x  Class(sensor ) 2

+ Performanc e class(PMD SS) 2

NOTE In a three-phase system, the class of the three sensors is equal to the class of one sensor provided that the three sensors have the sam e class.

The overall system performance class is rounded up to the closest standard default value (see Table D.4). For example, a class 1 PMD and a class 1 CS will give an overall system performance class equivalent to c lass 2.

D.3

PMD with external current sensor and voltage sensor

Table D.2 gives some recommendations when associating a PMD with an external current sensor and an external voltage sensor. Table D.2 – PMD SS with current sensor and voltage sensor association Performance class of the PMD without external sensors

Recommended sensor class to associate to the PM D  b c

Expected performance class for PMD-SS including their external sensors

maximum possible sensor class to associate to the PMD a

0,1

0,1 or below

0,2

0,2

0,2

0,2 or below

0,5

0,5

0,5

0,5 or below

1

1

1

1 or below

2

2

2

2 or below

5

5

5

5 or below

10

a

This induces an acceptable loss of performance of the system.

b

For power and energy measurements, 0,2 S and 0,5 S class sensors are usually required.

c

Class sensor refers to classes defined in IEC 60044-1, IEC 60044-2, IEC 60044-7 and IEC 60044-8. When transducers replace sensors, class sensor refers to intrinsic uncertainty of the transducer.

Overall system performanc e class = 1 ,15 x  Class( current   _ sensor  ) 2

+ Class( voltage _ sensor  ) 2 + Performanc e class( PMD SS) 2

NOTE In a three-phase system, the class of the three sensors is equal to the class of one sensor provided that the three sensors have the sam e class.

The system performance class is rounded up to the closest standard default value (see Table D.4). For example, a class 1 PMD with a class 0,5 CS and a class 0,5 VS will give a system performance class equivalent to class 2.

D.4

Range of applicable performance classes

Each applicable performance class for each specific function of PMD is given in Clause 0 of this standard.

BS EN 61557-12:2008

 – 73 – 

Table D.3 gives a summary of all applicable performance classes. Table D.3 – Range of applicable performance classes for PMD without its associated external sensors 0,02

0,05

0,1

0,2

0,5

1

2

2,5

3

5

10

20

Table D.4 gives the list of applicable performance classes resulting from the calculations given in Clauses D.2 and D.3. Table D.4 – Range of applicable performance classes when calculating performance class of PMD with its associated external sensors 0,2

D.5

0,3

0,5

0,75

1

1,5

2

2,5

3

5

7,5

10

15

20

List of functions affected by uncertainty of external sensors

Table D.5 defines the influence of each kind of sensor on each function of a PMD. Table D.5 – List of functions affected by uncertainty of external sensors Symbol

Function

Current sensor

Voltage sensor

P a

Total active power

x

x

Q A, Q V

Total reactive power (arithmet ic or vector)

x

x

S A, S V

Total apparent power (arithmetic or vector)

x

x

E a

Total active energy

x

x

E rA, E rV

Total reactive energy (arithmeti c or vector)

x

x

E apA, E apV

Total apparent energy (arithmet ic or vector)

x

x

f

Frequency

-

-

I

Phase current

x

-

I N, I Nc

Neutral current (measured, calculated )

x

-

U

Voltage (L p -L g  o r L p -N)

-

x

PF A, PF V

Power factor (arithmeti c, vector)

x

x

P st , P lt

Flicker (short term, long term)

-

-

U dip

Voltage dips (L p -L g  or Lp -N)

-

x

U swl

Voltage swells (L p -L g  or Lp -N)

-

x

U int

Voltage Interruption (Lp -L g  o r L p -N)

-

x

U nba

Voltage Unbalance amplitude (Lp -N)

-

x

U nb

Voltage Unbalance phase and amplitude (Lp -L g  o r L p -N)

-

x

U h

Voltage harmonics

-

x

THD u , THD-R u

Voltage THD (refered to fundamental, refered to r.m.s. value)

-

x

I h

Current harmonics

x

-

THD i THD-R i

Current THD (refered to fundamental, refered to r.m.s. value)

x

-

Msv 

Mains signalling voltage

-

x

NOTE

"x" means "affects the function", "-" means “does not affect the function”

BS EN 61557-12:2008

 – 74 – 

Annex E (normative) Requirements applicable to PMD and to PMD-A

Table E.1 gives a summary of all applicable requirements for each kind of PMD. Table E.1 – Requirements applicable to PMD and to PMD-A Requirements applicable to PMD including PMD-A Scope

Clause 1

Normative references

Clause 2

Definitions

Clause 3

General requirements

Requirements applicable to PMD except PMD-A

Requirements applicable to PMD-A only

Subclause 4.7

Subclause 4.8

Subclause 6.1

Subclause 6.2

Subclause 4.1 Subclause 4.2 Subclause 4.3 Subclause 4.4 Subclause 4.5 Subclause 4.6

Performance requirements Mechanical requirements

Subclause 4.9

Safety requirements

Subclause 4.10

 Ana lo g o ut put s

Sub cla use 4.11

Marking and operating instruction

Clause 5

Type test

Subclause 6.1.14

Climatic tests

Subclause 6.1.12

EMC tests

Subclause 6.1.13

Routine Test

Subclause 6.3

Definitions of electrical parameters

 Ann ex A

Definitions of minimum, maximum, peak and demand measurements

 Ann ex B

Intrinsic uncertainty, operating uncertainty, and overall system uncertainty

 Ann ex C

Recommended sensors classes for the different kind of PMD

 Ann ex D

BS EN 61557-12:2008

 – 75 – 

Bibliography IEC 60044-1:1996, Instrument transformers – Part 1: Current transformers NOTE Harmonized as EN 60044-1:1999 (modified).

IEC 60044-2:1997, Instrument transformers – Part 2: Inductive voltage transformers NOTE Harmonized as EN 60044-2:1999 (modified).

IEC 60044-7:1999, Instrument transformers – Part 7: Electronic voltage transformers NOTE Harmonized as EN 60044-7:2000 (not modified).

IEC 60044-8:2002, Instrument transformers – Part 8: Electronic current transformers NOTE Harmonized as EN 60044-8:2002 (not modified).

IEC 60050-131:2002, International Electrotechnical Vocabulary – Part 131: Circuit theory IEC 60050-161:1990, International Electromagnetic compatibility

Electrotechnical

Vocabulary

–

Chapter

161:

IEC 60050-300:2001, International Electrotechnical Vocabulary – Electrical and electronic measurements and measuring instruments – Part 311: General terms relating to measurements – Part 312: General terms relating to electrical measurements – Part 313: Types of electrical measuring instruments – Part 314: Specific terms according to the type of instrument  IEC 60050-551-20:  International Electrotechnical Vocabulary – Part 551-20: Power electronics  – Harmonic analys is IEC 60050-601:1985,  International Electrotechnical Vocabulary – Chapter 601: Generation, transmission and distribution of electricity – General  IEC 60050-604:1987, International Electrotechnical Vocabulary – Chapter 604: Generation, transmission and distribution of electricity – Operation IEC 60071-1:2006, Insulation co-ordination – Part 1: Definitions, principles and rules NOTE Harmonized as EN 60071-1:2006 (not modified).

IEC 60359:2001,  performance

Electrical

and

electronic

measurement

equipment

–

Expression

of

NOTE Harmonized as EN 60359:2002 (not modified).

IEC 60364-5-52:2001, El ectrical installations of buildings – Part 5-52: Selection and erection of electrical equipment – Wiring systems IEC 61000-4-7:2002, Electromagnetic compatibility (EMC) – Part 4-7: Testing and measurement techniques – General guide on harmonics and interharmonics measurements and instrumentation, for power supply systems and equipment connected thereto NOTE Harmonized as EN 61000-4-7:2002 (not modified).

IEC 61140:2001, Protection against electric shock – Common aspects for installation and equipment NOTE Harmonized as EN 61140:2002 (not modified).

BS EN 61557-12:2008

 – 76 – 

IEC 61010-2-030:___  1 ), Safety requirements for electrical equipment for measurement, control, and laboratory use – Part 2-030: Special requirements for testing and measuring circuits IEC 62052-11:2003, Electricity metering equipment (AC) – General requirements, tests and test conditions – Part 11: Metering equipment  NOTE Harmonized as EN 62052-11:2003 (not modified).

IEEE 1459-2000: IEEE Standard Definitions for the Measurement of Electric Power Quantities Under Sinusoidal, Nonsinusoidal, Balanced, or Unbalanced Conditions  ___________

——————— 1) In preparation.

 – 77 – 

BS EN 61557-12:2008

Annex ZA

(normative) Normative references to international publications with their corresponding European publications The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies.

Publication IEC 60068-2-1

Title EN/HD Environmental testing EN 60068-2-1 Part 2-1: Tests - Test A: Cold IEC 60068-2-2 Environmental testing EN 60068-2-2 Part 2-2: Tests - Test B: Dry heat IEC 60068-2-30 Environmental testing EN 60068-2-30 Part 2-30: Tests - Test Db: Damp heat, cyclic (12 h + 12 h cycle) IEC 60364-6 (mod) Low voltage electrical installations HD 60364-6 Part 6: Verification IEC 60529 Degrees of protection provided by enclosures EN 60529 (IP Code) + corr. May IEC 61000-4-5 Electromagnetic compatibility (EMC) EN 61000-4-5 Part 4-5: Testing and measurement techniques - Surge immunity test IEC 61000-4-15 Electromagnetic compatibility (EMC) EN 61000-4-15 Part 4-15: Testing and measurement techniques - Flickermeter - Functional and design specifications IEC 61000-4-30 2003 Electromagnetic compatibility (EMC) EN 61000-4-30 Part 4-30: Testing and measurement techniques - Power quality measurement methods IEC 61010 Series Safety requirements for electrical equipment EN 61010 for measurement, control, and laboratory use IEC 61010-1 2001 Safety requirements for electrical equipment EN 61010-1 for measurement, control, and laboratory + corr. June use Part 1: General requirements IEC 61326-1 2005 Electrical equipment for measurement, control EN 61326-1 and laboratory use - EMC requirements Part 1: General requirements IEC 61557-1 2007 Electrical safety in low voltage distribution EN 61557-1 systems up to 1 000 V a.c. and 1 500 V d.c. Equipment for testing, measuring or monitoring of protective measures Part 1: General requirements

1)

Year - 1)

 Undated reference.  Valid edition at date of issue.

2)

Year 2007 2) 2007 2005 2007 1991 1993 2006

1998

2003

Series 2001 2002

2006

2007

BS EN 61557-12:2008

Publication IEC 62053-21

Year 2003

IEC 62053-22

2003

IEC 62053-23

2003

IEC 62053-31

1998

 – 78 – 

Title Electricity metering equipment (a.c.) Particular requirements Part 21: Static meters for active energy (classes 1 and 2) Electricity metering equipment (a.c.) Particular requirements Part 22: Static meters for active energy (classes 0,2 S and 0,5 S) Electricity metering equipment (a.c.) Particular requirements Part 23: Static meters for reactive energy (classes 2 and 3) Electricity metering equipment (a.c.) Particular requirements Part 31: Pulse output devices for electromechanical and electronic meters (two wires only)

EN/HD EN 62053-21

Year 2003

EN 62053-22

2003

EN 62053-23

2003

EN 62053-31

1998

 – 79 – 

BS EN 61557-12:2008

Annex ZZ

(informative) Coverage of Essential Requirements of EC Directives This European Standard has been prepared under a mandate given to CENELEC by the European Commission and the European Free Trade Association and within its scope the standard covers all relevant essential requirements as given in Annex I of the EC Directive 2004/108/EC. Compliance with this standard provides one means of conformity with the specified essential requirements of the Directive concerned. WARNING: Other requirements and other EC Directives may be applicable to the products falling within the scope of this standard.  __________