Bansal Institute of Science &Technology Kokta, Anand nagar, Bhopal (M.p )
(RGPV, BHOPAL)
PRESENTATION SYNOPSIS PRESENT PRESE NTA ATION ON:
―3
Phase Fault Detection ’
Department of electrical & Department Electronics (EX) SUBM I TTED TO: TO: -
SUBM I TTED BY:- BY:-
Prof.:- Ra Ravi vi Ve Verm rm a
Ni raj kumar
H ead of th e elec electr tr ical & elec lectr tr oni cs Dep Department:- artment:-
Mr. Ravi Verma
DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING BANSAL INSTITUTE OF SCIENCE & TECHNOLOGY, BHOPAL (M.P)
May, 2012
I hereby certify that the work which is being presented in the B.E. Minor Project Report entitled “3 PHASE FAULT DETECTION” DETECTION ” , in partial fulfillment of the requirements for the award of t he degree of Bachelor of Engineering in Electrical and Electronics Engineering and submitted to the Department of
Electrical and Electronics Engineering , Bansal Institute of Science and Technology , Bhopal (M.P.) is is an authentic record of my team work carried out out during the period from Jan Jan 2012 to April 2012 under the supervision of Prof. Ravi Verma EX Department. The content presented in this project has not been submitted by my team for the award of any other degree elsewhere. Signature of Candidate
Niraj Kumar
This is to certify that the above statement made by the candidates is correct to the best of my knowledge.
Date:
Project Coordinator
HOD
Principal
Prof. – Prof. – Ravi Verma
Ravi Verma
prof. A.M Jain
DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING BANSAL INSTITUTE OF SCIENCE & TECHNOLOGY, BHOPAL (M.P)
May, 2012
I hereby certify that the work which is being presented in the B.E. Minor Project Report entitled “3 PHASE FAULT DETECTION” DETECTION ” , in partial fulfillment of the requirements for the award of t he degree of Bachelor of Engineering in Electrical and Electronics Engineering and submitted to the Department of
Electrical and Electronics Engineering , Bansal Institute of Science and Technology , Bhopal (M.P.) is is an authentic record of my team work carried out out during the period from Jan Jan 2012 to April 2012 under the supervision of Prof. Ravi Verma EX Department. The content presented in this project has not been submitted by my team for the award of any other degree elsewhere. Signature of Candidate
Niraj Kumar
This is to certify that the above statement made by the candidates is correct to the best of my knowledge.
Date:
Project Coordinator
HOD
Principal
Prof. – Prof. – Ravi Verma
Ravi Verma
prof. A.M Jain
ACKNOWLEDGMENT
This project involved the collection and analysis of information from a wide variety of sources and the efforts of many people beyond us. Thus it would not have been possible to achieve the results reported in this document without their help, support and encouragement. encouragement. I would like to express my gratitude to the following people for their help in the work leading to this report:
Prof. A.M Jain sir Principal BIST Bhopal (M.P) for providing us with an environment to complete our project successfully.
Prof. Ravi Verma Head, Department of Electrical and Electronics branch, who modeled us both technically and morally for achieving the greater success to complete the project and for organizing and coordinating the B.E. Projects’ 2012.
Prof. Ravi Verma Project Coordinator for their useful comments on the subject matter and for the knowledge I gained by sharing ideas with them. We also thank all the staff members of our department, college and technicians for their help in making this project a successful one. Finally, we take this opportunity to extend our deep appreciation to our family and friends, for all that they meant to us during the crucial times of the
completion of our project.
Niraj Kumar
CONTENTS 1. INTRODUCTION
2. CIRCUIT DIAGRAM
3. P.C.B LAYOUT
4. WORKING
5. APPLICATIONS
6. LIMITATION
7. FUTURE ENHANCEMENT
8. COMPONENT LIST
9. COMPONENT DESCRIPTION
10.
SOFTWARE
11.
REFERENCES
INTRODUCTION Three phase fault detector projects equipments mostly motors from destructive line conditions. When one of the 3 phases goes off the 3 phase fault detector/analyzer detects and the buzzer starts operating and the relay gets connected to the motor and the motor is prevented from getting damaged.
The output of the relay can be used either in set mode or reset mode , as well as the output of the relay can be used any where 3 phase supply is needed like heavy machines , power supplies etc.
The linear advantage of this circuit is that it cans automatically saves the complete system being get damaged automatically as well as it also provides a check on the phase which gets start after the disruption.
+5V
1K
+5V
L
1
4N35 N
1K
10k
5
2
103 4
+5V
+5V
1K
+5V
L
14 9
1
4N35 N
1K
10k
5
2
103
5
8
+5V
7 4075
1K
+5V 1
4N35 N
1 2 6
4
4
L
BUZZER
3
1K
10k
+5V
5
2
103 4
8
4
220K
555 2,6
3
+12V
100UF 5
4.7K
103
1K
CIRCUIT DIAGRAM
1
PCB LAYOUT
WORKING The ckt consists of 3 optopccouplers which are connected to the main supply. The 230v main ac supply is step down to the required level by the use of step down transformer. The optocouplers consist of a LED and an open transistor. The transistor and LED are optically coupled. When the +ve of ac supply is applied a large reverse voltage appears across the opt coupler which may damage the LED, thus to avoid this LED in opposite polarity is connected in parallel to the opt coupler LED. Which operates for the negative pulse? A capacitor is connected in series to the opt coupler this capacitor gets charged for the negative cycle but the charge is not the large enough to cross the threshold level. So that it can show logic 1. Therefore both the positive and negative logic 0 appears at the or gate so the output of or gate is low and the 555 timer does not operate. But when any one of phase goes off at that time the optocoupler corresponding to that phase does not operate and the capacitor connected begins to charge and when it cross the threshold value the corresponding input to the OR gate becomes high and thus the o/p of OR gate is high. As a result the capacitor connected to the OR gate starts charging and after the time period of 1.1 RC gets fully charged. During this duration the 555 timer does not operate as the required voltage level does not appear across the pins 2 & 6 of the 555 timer.
After this duration voltage at pin 2&6 becomes equal to the desired voltage as the capacitor starts discharging. And till the duration the i/p across the pin 2&6 does not becomes less than 2/3 vcc, the o/p of pin 3 of 555 timer becomes high as a result the transistor whose collector is connected to the relay starts operating and the relay also starts operating and the buzzer is on and hence we get the indication that all the 3 phases of the supply are not present…
COMPONENT LIST
1. IC’s
Number
Quantity
Rate/P.
CD4075
1
22.00
NE555
1
12.00
LM7805 4N35
1 3
10.00 30.00
1
3.00
2. Transistors
BC548B
3. Light Emitting Diodes (LED’s)
Red
4
1.50
4. Diodes
1N4007
3
1.50
5. Electrolytic Capacitors
1000F/25V
1
7.00
100F/25V
1
4.00
1F/25V
3
3.00
6. Ceramic Capacitors
104pf
1
1.00
7. Carbon Resistors (0.25W)
220K 1K
7 3
0.25 0.25
3.3k
1
0.25
100E
1
0.25
1
25.00
1
40.00
8. Relays
12V/200E 9. Transformers
9/0/9 500mA
10. PCB
3” X 4”
1
90.00
11. Miscellaneous
IC Base (14 pin)
1
6.00
IC Base (8 pin) Mains Cable
4 1
3.00 15.00
Ferric Chloride
100gms.
40.00
Soldering Wire
20gms.
12.00
2mtrs.
10.00
10gms.
5.00
Connecting wires Soldering Paste
COMPONENT DESCRIPTION
RESISTORS: The electrical resistance of a circuit component or device is defined as the ratio of the voltage applied to the electric current which flows through it:
If the resistance is constant over a considerable range of voltage, then Ohm's law, I = V/R, can be used to predict the behavior of the material. Although the definition above involves DC current and voltage, the same definition holds for the AC application of resistors.
A Resistor is a heat-dissipating element and in the electronic circuits it is mostly used for either controlling the current in the circuit or developing a voltage drop across it, which could be utilized for many applications. There are various types of resistors, which can be classified according to a number of factors depending upon: (I)
Material used for fabrication
(II) Wattage and physical size (III) Intended application (IV) Ambient temperature rating (V) Cost Basically the resistor can be split in to the following four parts from construction viewpoint.
the
(1) Base (2) Resistance element (3) Terminals (4) Protective means. The following characteristics are inherent in all resistors and may be controlled by design considerations and choice of material i.e. Temperature co – efficient of resistance, Voltage co – efficient of resistance, high frequency characteristics, power rating, tolerance & voltage rating of resistors. Resistors may be classified as (1)Fixed (2)Semi variable (3)Variable resistor. Resistor Combinations :The combination rules for any number of resistors
in series or parallel can be derived with the use of Ohm's Law , the voltage
law ,
and
the
current
law
In our project carbon resistors are being used
CAPACITORS
The fundamental relation for the capacitance between two flat plates separated by a dielectric material is given by:-
C=0.08854KA/D Where: -
C= capacitance in pf. K= dielectric constant A=Area per plate in square cm. D=Distance between two plates in cm
Design of capacitor depends on the proper dielectric material with particular type of application. The dielectric material used for capacitors may be grouped in various classes like Mica, Glass, air, ceramic, paper, Aluminum, electrolyte etc. The value of capacitance never remains constant. It changes with temperature, frequency and aging. The capacitance value marked on the capacitor strictly applies only at specified temperature and at low frequencies.
LED (Light Emitting Diodes)
As its name implies it is a diode, which emits light when forward biased. Charge carrier recombination takes place when electrons from the N-side cross the junction and recombine with the holes on the P side. Electrons are in the higher conduction band on the N side whereas holes are in the lower valence band on the P side. During recombination, some of the energy is given up in the form of heat and light. In the case of semiconductor materials like Gallium arsenide (GaAs), Gallium phosphate (Gap) and Gallium arsenide phosphate (GaAsP) a greater percentage of energy is released during recombination and is given out in the form of light. LED emits no light when junction is reversing biased.
TRANSISTOR: -
A transistor consists of two junctions formed by sandwiching either p-type or n-type semiconductor between a pair of opposite types. Accordingly, there are two types of transistors namely: (1) n-p-n transistor
(NPN)
(2) p-n-p transistor
(PNP)
An n-p-n transistor is composed of two n-type semiconductors separated by a thin section of p type. However a p-n-p transistor is formed by two p sections separated by a thin section of n-type. In each type of transistor the following points may be noted.
1.
There are two p-n junctions; therefore a transistor may be regarded as combination of two diodes connected back to back.
2.
There are three terminals taken from each type of semiconductor.
3.
The middle section is a very thin layer, which is the most important factor in the functioning of a transistor.
4.
Transistor can be used as an Amplifier also. A transistor raises the strength of a weak signal and thus acts as an
amplifier. The weak signal is applied between emitter base junction and output is taken across the load RC connected in the collector circuit (in common emitter configuration). In order to achieve faithful amplification, the input circuit should always remain forward biased. To do so, a dc voltage is applied in the input in addition to the signal. This dc Voltage is known as biasing voltage and its magnitude and polarity should be such that it always keeps the input circuit forward biased regardless of the polarity to the signal to be amplified. As the input circuit has low resistance a small change in signal voltage causes an appreciable change in emitter current. This causes change in collector current (by a factor called current gain of transistor) due to transistor action. The collector current flowing through a high load resistance RC produces a large voltage across it. Thus a weak signal applied to the input circuit appears in the amplified form in the collector circuit. This is how a transistor acts as an amplifier.
Transistor may be used in different configuration like CB (common base) & CC (common collector) according to requirements of amplifier (impedance matching, buffer amplifier etc.).
TRANSFORMER
Definition: The transformer is a static electro-magnetic device that transforms one alternating voltage (current) into another voltage (current). However, power remains the some during the transformation. Transformers play a major role in the transmission and distribution of ac power.
Principle: -
Transformer works on the principle of mutual induction. A transformer consists of laminated magnetic core forming the magnetic frame. Primary and secondary coils are wound upon the two cores of the magnetic frame, linked by the common magnetic flux. When an alternating voltage is applied across the primary coil, a current flows in the primary coil producing magnetic flux in the transformer core. This flux induces voltage in secondary coil.
Transformers are classified as: (a)
(b)
Based on position of the windings with respect to core i.e. (1)
Core type transformer
(2)
Shell type transformer
Transformation ratio: (1)
Step up transformer
(2)
Step down transformer
(a)
Core & shell types: Transformer is simplest electrical machine, which consists of windings on the laminated magnetic core. There are two possibilities of putting up the windings on the core.
(1)
Winding encircle the core in the case of core type transformer
(2)
Cores encircle the windings on shell type transformer.
(b)
Step up and Step down: In these Voltage transformation takes place according to whether the Primary is high voltage coil or a low voltage coil.
(1)
Lower to higher-> Step up
(2)
Higher to lower-> Step down
DIODES -
+
It is a two terminal device consisting of a P-N junction formed either of Ge or Si crystal. The P and N type regions are referred to as anode and
cathode respectively. Commercially available diodes usually have some means to indicate which lead is P and which lead is N.
RELAY
In this circuit a 12V magnetic relay is used. In magnetic relay, insulated copper wire coil is used to magnetize and attract the plunger .The plunger is normally connected to N/C terminal. A spring is connected to attract the plunger upper side. When output is received by relay, the plunger is attracted and the bulb glows.
Dip Trace is a complete state-of-the-art PCB Design System. It includes:
PCB Layout — PCB designs with an easy to use manual routing tools, auto-router and auto-placer. Schematic — Schematic Capture and export to PCB or Spice. Pattern Editor — allows you to create part footprints. Component Editor — allows you to draw parts and make components.
Dip Trace provides the following features:
Easy to learn user interface
To design a schematic, simply select and place components onto your document and connect them together using the wire and bus tools. Multisheet design is supported. Then select the menu option 'Convert to PCB' to convert the schematic to PCB. Layout can be updated from Schematic in a few clicks at anytime. When you create or edit design objects they are highlighted to improve your work. Step-by-step tutorial
available from web-site guides you through the design process and allows to get started with ease. Smart placement and auto-placement features
After converting Schematic to PCB layout, place board outline and arrange components. Then use "placement by list" for chips/connectors and auto-placement for other components to get acceptable result in a few minutes and start routing. Easy to use manual and powerful automatic routing
Dip Trace PCB software includes an advanced automatic router that is able to route single-layer and multi-layer boards. It is available with a 'rip-up and retry' algorithm. Auto router achieves high completion rates by going back and re-routing nets to make space for connections that could not be routed on a previous pass. Intelligent manual routing tools allow you to create and edit traces by 90, 45 degree or without any limitations. Through, blind or buried visa can be used in automatic and manual routing. Unlimited board size is supported. Shape-based copper pour
Powerful copper pour system can help to reduce your manufacturing costs by minimizing the amount of etching solution required. To use it, all you have to do is insert a copper area on your board in the PCB Layout program and any pad or trace inside the selected area will be automatically surrounded with a gap of the desired size. Using copper pour you can also create planes and connect them to pads and visa (different thermal types are supported).
Advanced Verification Features
Schematic and PCB design modules have number of verification features that help control project accuracy on different design stages: The ERC function shows possible errors in Schematic pin connections using defined rules and allows you to correct errors step-by-step. DRC function checks the clearance between design objects, minimum size of traces, and drills. Errors are displayed graphically and you can fix them step-by-step and rerun the DRC in one click after any corrections. Net Connectivity Check verifies if all nets of PCB are electrically connected. This feature uses traces; copper pour filled area and shapes to control connectivity, and then reports broken and merged nets with area details. Comparing to Schematic allows you to check if routed PCB is identical with Schematic. Spice Support
Using Dip Trace Schematic or Component Editor specify spice settings or attach models to the components. Then export .cir net-list of your Schematic to LT Spice or another simulation software to verify how it works. Import/Export Features
Package modules allow you to exchange schematics, layouts and libraries with other EDA and CAD packages. Dip Trace Schematic Capture and PCB Layout also support Accel, Allegro, Mentor, PADS, PCAD, Protel and Tango net list formats. Manufacturing output formats
Dip Trace provides support for a number of different manufacturing output formats. Using this PCB software you can produce N/C Drill files for numerically controlled (N.C.) drilling machines and RS-274X Gerber files for sending to board manufacturers. Vector zing function allows exporting true-type fonts and raster images. Also Dip Trace supports DXF output.
Standard component libraries
Dip Trace package includes component and pattern libraries, which contain 50.000+ components from different manufacturers. Creation of your own libraries
Component and Pattern Editors allow designing your own symbols and patterns. To create complete components simply connect them together using Component Editor.
PCB Design Service We recognize that there may come a time when you need to get a project urgently completed or just don't have the resources to do it. So our Engineering Department offers the following services:
Designing single-, double- and multilayer printed circuit boards; High density of component layout, subject to assembly conditions; Designing boards with analog, digital and mixed components; PCB routing for high-speed, including routing of differential pairs and impedance control routing; RF Circuits; Designing boards for high voltage; Flex Circuits; Library creation.
Design process includes:
Creation of schematic file (if it's not provided by the customer); Creation of a library with missing components; Schematic verification (ERC); Importing Schematic or Net list into PCB Layout; Routing the layout (automatic and/or manual); Comparing PCB Layout to existing Schematic; Routing quality analysis (DRC, Connectivity check, Impedance control, etc.), making necessary changes; Adjustment of Dip Trace PCB Layout file based on customer comments; Creation of Gerber/Drill/DXF files for PCB manufacturing, checking files using Dip Trace and third-party viewers; Preparing all the documents needed.
When design is finished, the customer receives the following files:
Dip Trace Schematic and PCB files; Gerber and Drill files, DXF file (all files formatted to meet your PCB manufacture’s requirements); Bill of materials (Excel compatible format); Layout chart to assemble components, Pick and Place report (Excel compatible format and/or text file); Other documents, if needed.
Please provide the following details to get final quote and start working:
Dip Trace Schematic (.dch file), Schematic picture (JPEG, GIF or PNG) or net list (Accel, Allegro, Mentor, PADS, P-CAD, Protel 2.0 or Tango).
Size of PCB, the drawing is preferred for complex board outline (DXF or picture); mounting hole diameters and positions, component positions if required, areas free from traces (if such exist), etc. Trace width, clearance, via size, ring size, etc. Number of layers (fixed or preferred). Datasheets or drawings for non-standard components. Your PCB manufacturer or his requirements. Your other requirements.
P.C.B. MANUFACTURING PROCESS It is an important process in the fabrication of electronic equipment. The design of PCBs (Printed Circuit Boards) depends on circuit requirements like noise immunity, working frequency and voltage levels etc. High power PCBs requires a special design strategy. The fabrication process to the printed circuit board will determine to a large extent the price and reliability of the equipment. A common target aimed is the fabrication of small series of highly reliable professional quality PCBs with low investment. The target becomes especially important for customer tailored equipments in the area of industrial electronics.
The layout of a PCB has to incorporate all the information of the board before one can go on the artwork preparation. This means that a concept which clearly defines all the details of the circuit and partly defines the final equipment, is prerequisite before the actual lay out can start. The detailed circuit diagram is very important for the layout designer but he must also be familiar with the design concept and with the philosophy behind the equipment.
BOARD TYPES:
The two most popular PCB types are: 1.
Single Sided Boards
The single sided PCBs are mostly used in entertainment electronics where manufacturing costs have to be kept at a minimum. However in industrial electronics cost factors cannot be neglected and single sided boards should be used wherever a particular circuit can be accommodated on such boards. 2.
Double Sided Boards
Double-sided PCBs can be made with or without plated through holes. The production of boards with plated through holes is fairly expensive. Therefore plated through hole boards are only chosen where the circuit complexities and density of components does not leave any other choice.
DESIGN SPECIFICATION
(I)
STEPS TAKEN WHILE PREPARING CIRCUIT
(A)
PCB DESIGNING
The main purpose of printed circuit is in the routing of electric currents and signal through a thin copper layer that is bounded firmly to an insulating base material sometimes called the substrate. This base is manufactured with integrally bounded layers of thin copper foil which has to be partly etched or removed to arrive at a pre-designed pattern to suit the circuit connections or other applications as required. The term printed circuit board is derived from the original method where a printed pattern is used as the mask over wanted areas of copper. The PCB provides an ideal baseboard upon which to assemble and hold firmly most of the small components. From the constructor’s point of view, the main attraction of using
PCB is its role as the mechanical support for small components. There is less need for complicated and time consuming metal work of chassis contraception except perhaps in providing the final enclosure. Most straight forward circuit designs can be easily converted in to printed wiring layer the thought required to carry out the inversion cab footed high light an possible error that would otherwise be missed in
conventional point to point wiring .The finished project is usually neater and truly a work of art.
Actual size PCB layout for the circuit shown is drawn on the copper board. The board is then immersed in FeCl3 solution for 12 hours. In this process only the exposed copper portion is etched out by the solution.
Now the petrol washes out the paint and the copper layout on PCB is rubbed with a smooth sand paper slowly and lightly such that only the oxide layers over the Cu are removed. Now the holes are drilled at the respective places according to component layout as shown in figure.
(B)
LAYOUT DESIGN:
When designing the layout one should observe the minimum size (component body length and weight). Before starting to design the layout we need all the required components in hand so that an accurate assessment of space can be made. Other space considerations might also be included from case to case of mounted components over the printed circuit board or to access path of present components.
It might be necessary to turn some components around to a different angular position so that terminals are closer to the connections of the components. The scale can be checked by positioning the components on the squared paper. If any connection crosses, then one can reroute to avoid such condition. All common or earth lines should ideally be connected to a common line routed around the perimeter of the layout. This will act as the ground plane. If possible try to route the outer supply line to the ground plane. If possible try to route the other supply lines around the opposite edge of the layout through the center. The first set is tearing the circuit to eliminate the crossover without altering the circuit detail in any way. Plan the layout looking at the topside to this board. First this should be translated inversely; later for the etching pattern large areas are recommended to maintain good copper adhesion. It is important to bear in mind always that copper track width must be according to the recommended minimum dimensions and allowance must be made for increased width where termination holes are needed. From this aspect, it can become little tricky to negotiate the route to connect small transistors.
There are basically two ways of copper interconnection patterns underside the board. The first is the removal of only the amount of copper necessary to isolate the junctions of the components to one another. The second is to make the interconnection pattern looking more like conventional point wiring by routing uniform width of copper from component to component.
(C)
ETCHING PROCESS:
Etching process requires the use of chemicals. Acid resistant dishes and running water supply. Ferric chloride is mostly used solution but other etching materials such as ammonium per sulphate can be used. Nitric acid can be used but in general it is not used due to poisonous fumes. The pattern prepared is glued to the copper surface of the board using a latex type of adhesive that can be cubed after use. The pattern is laid firmly on the copper using a very sharp knife to cut round the pattern carefully to remove the paper corresponding to the required copper pattern areas. Then apply the resistant solution, which can be a kind of ink solution for the purpose of maintaining smooth clean outlines as far as possible. While the board is drying, test all the components.
Before going to next stage, check the whole pattern and cross check With the circuit diagram. Check for any free metal on the copper. The etching bath should be in a glass or enamel disc. If using crystal of ferricchloride these should be thoroughly dissolved in water to the proportion suggested. There should be 0.5 lt. of water for 125 gm of crystal. To prevent particles of copper hindering further etching, agitate the solutions carefully by gently twisting or rocking the tray. The board should not be left in the bath a moment longer than is needed to remove just the right amount of copper. Inspire of there being a resistive coating there is no protection against etching away through exposed copper edges. This leads to over etching. Have running water ready so that etched board can be removed properly and rinsed. This will halt etching immediately. Drilling is one of those operations that call for great care. For most purposes a 0.5mm drill is used. Drill all holes with this size first those that need to be larger can be easily drilled again with the appropriate larger size.
(D) COMPONENT ASSEMBLY: From the greatest variety of electronic components available, which runs into thousands of different types it is often a perplexing task to know which is right for a given job.
There could be damage such as hairline crack on PCB. If there are, then they can be repaired by soldering a short link of bare copper wire over the affected part. The most popular method of holding all the items is to bring the wires far apart after they have been inserted in the appropriate holes. This will hold the component in position ready for soldering. Some components will be considerably larger .So it is best to start mounting the smallest first and progressing through to the largest. Before starting, be certain that no further drilling is likely to be necessary because access may be impossible later. Next will probably be the resistor, small signal diodes or other similar size components. Some capacitors are also very small but it would be best to fit these afterwards. When fitting each group of components mark off each one on the circuit as it is fitted so that if we have to leave the job we know where to recommence.
Although transistors and integrated circuits are small items there are good reasons for leaving the soldering of these until the last step. The main point is that these components are very sensitive to heat and if subjected to prolonged application of the soldering iron, they could be internally damaged. All the components before mounting are rubbed with sand paper so that oxide layer is removed from the tips. Now they are mounted according to the component layout.
(E) SOLDERING: This is the operation of joining the components with PCB after this operation the circuit will be ready to use to avoid any damage or fault during this operation following care must be taken.
1. A longer duration contact between soldering iron bit & components lead can exceed the temperature rating of device & cause partial or total damage of the device. Hence before soldering we must carefully read the maximum soldering temperature & soldering time for device. 2. The wattage of soldering iron should be selected as minimum as permissible for that soldering place.
3. To protect the devices by leakage current of iron its bit should be earthed properly. 4. We should select the soldering wire with proper ratio of Pb & Tin to provide the suitable melting temperature. 5. Proper amount of good quality flux must be applied on the soldering point to avoid dry soldering.
APPLICATIONS:
Identify and locate – Faults & defects in any of the 3 on line phases. Condition based monitoring of faults, in line variations, during commissioning And while in-service. It can be used by itself or in conjunction with Other in-service test results for assisting in decision makeIng process or switching.
ADVANTAGES:
Rapid Results – It is quick and easy to Configure, giving results in seconds Reliability and Ease of Use – It produces High quality results with high repeatability allowing for Rapid and reliable decision making Rugged and Reliable – It is a circuit with outstanding durability for field use Simple User-friendly interface
LIMITATIONS:
It is only useful for house-hold or low voltages up to 230 volts It is not usable for H.T Lines FUTURE PROSPECTIVE:
It can be made more reliable and useful by employing microcontroller LCD displays & Sensors. It can be employed for Hotlines with the use of high ratings relays, in conjunction with Instrument Transformers.
CHRONOLOGY The following steps have been followed in carrying out the project. 1.
Study the books on the relevant topic.
2.
Understand the working of the circuit.
3.
Prepare the circuit diagram.
4.
Prepare the list of components along with their specification. Estimate the cost and procure them after carrying out market survey.
5.
Plan and prepare PCB for mounting all the components.
6.
Fix the components on the PCB and solder them.
7.
Test the circuit for the desired performance.
8.
Trace and rectify faults if any.
9.
Give good finish to the unit.
10.
Prepare the project report.
