Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
LAB MANUAL UTILIZATION OF ELECTRICAL ENERGY (3340903) th
IV SEMESTER Head of the department: Mrs Hetal Prajapati Prepared Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
This
is
to
certify
that
___________________________ ______________ _____________________ ________
,
_________________________ ______________ ___________
in
studying
Mr./Miss
Enrollment Enrollm ent
number
4th semester of
_______________ ______________ _ department departme nt of Parul Institute of Engineering En gineering and Technology
(Diploma
studies)
______shift,
has
satisfactorily
completed and submitted the course of subject (with code) ___________________________ ______________ _____________________ ________
during the Academic Academi c
year________..
Date of submission:___________. Signature of Subject In charge:_______. Signature of Head of the Department.____________.
Head of the department: Mrs Hetal Prajapati Prepared Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
This
is
to
certify
that
___________________________ ______________ _____________________ ________
,
_________________________ ______________ ___________
in
studying
Mr./Miss
Enrollment Enrollm ent
number
4th semester of
_______________ ______________ _ department departme nt of Parul Institute of Engineering En gineering and Technology
(Diploma
studies)
______shift,
has
satisfactorily
completed and submitted the course of subject (with code) ___________________________ ______________ _____________________ ________
during the Academic Academi c
year________..
Date of submission:___________. Signature of Subject In charge:_______. Signature of Head of the Department.____________.
Head of the department: Mrs Hetal Prajapati Prepared Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
TUT NAME OF TUTORIAL . NO 1
2
3
5
Identify the different lighting accessories required for various types of lamps.
Sign
Prepare a technical report after visiting an industry, manufacturing electrical heating furnaces. (otherwise from internet) Prepare a report of specification of various heating furnaces used in industries.
9
Prepare a report of specification of various electrical welding machines available in college workshop. Prepare a report on various elevators after visiting nearby elevators manufacturing/repairing industry.
10
Compare Compare various Electric Drives for Traction
11
Select the appropriate motors and justify j ustify selection for given different load situations (at least 5)
12
Given a specific load co ndition determine the rating of a motor (motor for a pump, motor for a lift).
13
Prepare a report after visiting nearby electrictraction substation. (otherwise from Internet)
14
Prepare a report /chart on various types traction systems.
15
Prepare a report/chart on speed time curves.
8
Marks
Prepare a survey report after collecting technical information of various lamps available in the local market. Prepare an industrial visit report after visiting nearby lamp manufacturing industry (otherwise from internet) Prepare a report of different luminaries available in the market & collect the technical data.
7
Date
Measure Illumination at different places in college by luxmeter
4
6
PAGE NO.
Head of the department: Mrs Hetal Prajapati Prepared Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Practical:1 Measure Illumination at different places in college by luxmeter.
S.no. 1 2 3 4 5
Location
Head of the department: Mrs Hetal Prajapati Prepared Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
2
Lux(lumen/m )
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 2
Prepare a survey report after collecting technical information of various lamps available in the local market. Types of lamps (I)Incandescent light bulb The modern incandescent lightbulb, with a coiled filament of tungsten, was commercialized in the 1920s developed from the carbon filament lamp introduced in about 1880. As well as bulbs for normal illumination, there is a very wide range, including low voltage, low -power types often used as components in equipment, but now largely displaced by LEDs There is currently interest in banning some types of filament lamp in some countries, such as Australia planning to ban standard incandescent light bulbs by 2010, because they are inefficient at converting electricity to light. Sri Lanka has already banned importing filament bulbs because of high use of electricity and less light. Less than 3% of the input energy is converted into usable light. Nearly all of the input energy ends up as heat that, in warm climates, must then be removed from the building by ventilation or air conditioning, often resulting in more energy consumption. In colder climates where heating and lighting is required during the cold and dark winter months, the heat byproduct has at least some value.
Figure 2.1 Incandescent lamp (II) Halogen lamp
Halogen lamps are usually much smaller than standard incandescents, because for successful operation a bulb temperature over 200 °C is generally necessary. For this reason, most have a bulb of fused silica sili ca (quartz), but sometimes aluminosilicate alumin osilicate glass. g lass. This is i s often sealed inside a n
Head of the department: Mrs Hetal Prajapati Prepared Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering additional layer of glass. The outer glass is a safety precaution, reducing UV emission and because halogen bulbs can occasionally explode during operation. One reason is if the quartz bulb has oily residue from fingerprints. The risk of burns or fire is also greater with bare bulbs, leading to their prohibition in some places unless enclosed by the luminaire. Those designed for 12 V or 24 V operation have compact filaments, useful for good optical control, also they have higher efficiencies (lumens per watt) and better lives than non halogen types. The light output remains almost constant throughout life.
Figure 2.2 Halogen-tungsten lamp
(III) Fluorescent lamp
Fluorescent lamps have much higher efficiency than filament lamps. For the same amount of light generated, they typically use around one-quarter to one-third the power of an incandescent. Fluorescents were mostly limited to linear and a round 'Circline' lamp until the 1980s, with other shapes never gaining much popularity. The compact fluorescent lamp (CFL) was commercialized in the early 1980s. Most CFLs have a built-in electrical ballast and fit into a standard screw or bayonet base. Some make use of a separate ballast so that the ballast and tube can be replaced separately. Typical average lifetime ratings for linear fluorescent tubes are 10,000 and 20,000 hours, compared to 750 hours (110 V) and 1000 hours (240 V) for filament lamps.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Some types of fluorescent lamp ballast have difficulty starting lamps in very cold conditions, so lights used outdoors in cold climates need to be designed for outdoor use to work reliably. Fluorescents come in a range of different color temperatures. In some countries cool white (CW) is most popular, while in some, warmer whites predominate. In the United States, fluorescents most often come in cool white (CW), with some home bulbs being a warm white (WW), which has a pinkish color. In between there is an "enhanced white" (EW), which is more neutral. There is also a very cold daylight white (DW). Compact fluorescent lamps are usually considered warm white, though many have a yellowish cast like an incandescent. "Warm" and "cool" are entirely relative terms and almost arbitrary so color temperature and the color rendering index (CRI) are used as absolute scales of color for fluorescents, and sometimes for other types of lighting.
Figure 2.3 Fluorescent lamp
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 3
Prepare an industrial visit report after visiting nearby lamp manufacturing industry
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 4 Prepare a report of different luminaries available in the market & collect the technical data Different (i) (ii) (iii) (iv) (v)
luminaries available are Incandescent lamp Fluorescent lamps Electronic Ballast Tube light Light emitting diode
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 5
Identify the different lighting accessories required for various types of lamps
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 6 Prepare a technical report after visiting an industry, manufacturing electrical heating furnaces.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 7 Prepare a report of specification of various heating furnaces used in industries Types of heating furnaces used in industries:i) Forging Furnaces The forging furnace is used for preheating billets and ingots to attain a ‘forge’ temperature. The furnace temperature is maintained at around 1200 to 1250 oC. Forging furnaces, use an open fireplace system and most of the heat is transmitted by radiation. The typical loading in a forging furnace is 5 to 6 tonnes with the furnace operating for 16 to 18 hours daily. The total operating cycle can be divided into (i) heat-up time (ii) soaking time and (iii) forging time. Specific fuel consumption depends upon the type of material and number of ‘reheats’ required. ii) Rerolling Mill Furnace a) Batch type A box type furnace is employed for batch type rerolling mill. The furnace is basically used for heating up scrap, small ingots and billets weighing 2 to 20 kg. for rerolling. The charging and discharging of the ‘material’ is done manually and the final product is in the form of rods, strips etc. The operating temperature is about 1200 oC. The total cycle time can be further categorized into heat-up time and rerolling time. During heat-up time the material gets heated upto the required temperature and is removed manually for rerolling. The average output from these furnaces varies from 10 to 15 tonnes / day and the specific fuel consumption varies from 180 to 280 kg. of coal / tonne of heated material. b) Continuous Pusher Type: The process flow and operating cycles of a continuous pusher type is the same as that of the batch furnace. The operating temperature is about 1250 oC. Generally, these furnaces operate 8 to 10 hours with an output of 20 to 25 tonnes per day. The material or stock recovers a part of the heat in flue gases as it moves down the length of the furnace. Heat absorption by the material in the furnace is slow, steady and uniform throughout the cross-section compared with batch type. iii) Continuous Steel Reheating Furnaces The main function of a reheating furnace is to raise the temperature of a piece of steel, typically to between 900°C and 1250oC, until it is plastic enough to be pressed or rolled to the desired section, size or shape, The furnace must also meet specific requirements and objectives in terms of stock heating rates for metallurgical and productivity reasons. In
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering continuous reheating, the steel stock forms a continuous flow of material and is heated to the desired temperature as it travels through the furnace. All furnaces possess the features shown in Figure 4.1
Figure 7.1: Furnace feature
A refractory chamber constructed of insulating materials for retaining heat at the high operating temperatures. A hearth to support or carry the steel. This can consist of refractory materials or an arrangement of metallic supports that may be water-cooled. Burners that use liquid or gaseous fuels to raise and maintain the temperature in the chamber. Coal or electricity can be used for reheating. A method of removing the combustion exhaust gases from the chamber A method of introducing and removing the steel from the chamber. These facilities depend on the size and type of furnace, the shape and size of the steel being processed, and the general layout of the rolling mill. Common systems include roller tables, conveyors, charging machines and furnace pushers.
Types of Continuous Reheating Furnace Continuous reheating furnaces are primarily categorised by the method by which stock is transported through the furnace. There are two basic methods: Stock is butted together to form a stream of material that is pushed through the furnace. Such furnaces are called pusher type furnaces.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Stock is placed on a moving hearth or supporting structure which transports the steel through the furnace. Such types include walking beam, walking hearth, rotary hearth and continuous recirculating bogie furnaces.
The major consideration with respect to furnace energy use is that the inlet and outlet apertures should be minimal in size and designed to avoid air infiltration. i) Pusher Type Furnaces The pusher type furnace is popular in steel industry. It has relatively low installation and maintenance costs compared to moving hearth furnaces. The furnace may have a solid hearth, but it is also possible to push the stock along skids with water-cooled supports that allow both the top and bottom faces of the stock to be heated. The design of a typical pusher furnace design is shown schematically in Figure 4.2
Figure 7.2 Pusher type furnaces
Pusher type furnaces, however, do have some disadvantages, including: Frequent damage of refractory hearth and skid marks on material Water cooling energy losses from the skids and stock supporting structure in top and bottom fired furnaces have a detrimental effect on energy use; Discharge must be accompanied by charge: Stock sizes and weights and furnace length are limited by friction and the possibility of stock pile-ups.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering ii) Walking Hearth Furnaces The walking hearth furnace (Figure.4.3) allows the stock to be transported through the furnace in discrete steps. Such furnaces have several attractive features, including: simplicity of design, ease of construction, ability to cater for different stock sizes (within limits), negligible water cooling energy losses and minimal physical marking of the stock. The main disadvantage of walking hearth furnaces is that the bottom face of the stock cannot be heated. This can he alleviated to some extent by maintaining large spaces between pieces of stock. Small spaces between the individual stock pieces limits the heating of the side faces and increases the potential for unacceptable temperature differences within the stock at discharge. Consequently, the stock residence time may be long, possibly several hours; this may have an adverse effect on furnace flexibility and the yield may be affected by scaling .
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering iii) Rotary hearth furnace The rotary hearth furnace (Figure 4.4) has tended to supersede the recirculating bogie type. The heating and cooling effects introduced by the bogies are eli minated, so heat storage losses are less. The rotary hearth has, however a more complex design with an annular shape and revolving hearth.
Figure 7.4 Rotary hearth type furnace
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering iv) Continuous Recirculating Bogie type Furnaces These types of moving hearth type furnaces tend to be used for compact stock of variable size and geometry. In bogie furnaces (Figure 4.5), the stock is placed on a bogie with a refractory hearth, which travels through the furnace with others in the form of a train. The entire furnace length is always occupied by bogies. Bogie furnaces tend to be long and narrow and to suffer from problems arising from inadequate sealing of the gap between the bogies and furnace shell, difficulties in removing scale, and difficulties in firing across a narrow hearth width.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering v) Walking Beam Furnaces: The walking beam furnace (Figure 4.9) overcomes many of the problems of pusher furnaces and permits heating of the bottom face of the stock. This allows shorter stock heating times and furnace lengths and thus better control of heating rates, uniform stock discharge temperatures and operational flexibility. In common with top and bottom fired pusher furnaces, however, much of the furnace is below the level of the mill; this may be a constraint in some applications.
Figure 7.6 Walking beam furnace
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 8 Prepare a report of specification of various electrical welding machines available in college workshop
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 9 Prepare a report on various elevators after visiting nearby elevators manufacturing/repairing industry
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 10 Compare various Electric Drives for Traction
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 11 Select the appropriate motors and justify selection for given different load situations (at least 5) Sr. no.
Type of Load
1.
Electric fan, blower, pump
2.
Line shaft, conveyer grinder
3.
Conveyer, shearing punching machine
4.
Portable tool, mixer grinder, vacuum cleaner
5.
Electric clock, turn table, table fan
6.
Elevator, crane, hoist
7.
Electric locomotive
8.
Lathe, milling machine
9.
Coil winding machine
10.
Refrigeration and Airconditioning
Load characteristics
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
Type of motor
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 12 Given a specific load condition determine the rating of a motor (motor for a pump, motor for a lift) Sr. no.
Type of Load
1.
Electric fan, blower, pump
2.
Line shaft, conveyer grinder
3.
Conveyer, shearing punching machine
4.
Portable tool, mixer grinder, vacuum cleaner
5.
Electric clock, turn table, table fan
6.
Elevator, crane, hoist
7.
Electric locomotive
8.
Lathe, milling machine
9.
Coil winding machine
10.
Refrigeration and Airconditioning
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
Rating of motor
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 13 Prepare a report after visiting nearby electric-traction substation.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 14
Prepare a report /chart on various types traction systems. DIFFERENT SYSTEMS OF TRACTION
The description of commonly used traction systems is given below. 1. Steam engine drive. Steam engine drive, though losing ground gradually due to various reasons, it is still the amply adopted means of propulsion of railway work in underdeveloped coun-tries. In this type of drive, the reciprocating engine is invariably used for getting the necessary motive power. Advantages. Following are the adtgantagcs of steam engine drive : 1. Simplicity in design. 2. Simplified maintenance. 3. Easy speed control. 4. Simplicity of connections between the cylinders and the driving wheels. 5. No interference with communication network. 6. Low capital cost as track electrification is not required. 7. The locomotive and train unit is self contained, therefore, it is not tied to a route. 8. It is cheap for low density traffic areas and in initial stages of communication by rail. 9. Operational dependability. Disadvantages. This system, because of the followingdisadvantages, is being replaced even by the underdeveloped countries by either diesel electric or straight electric systems : 1. Low thermal efficiency. 2. The steam engine system is available for haulage for about 60 percent of its working time, the remainder of the time is spent in preparing for service, maintenance and overhaul. 3. Owing to unbalanced reciprocating parts there is a considerable wear on the track, and also riding qualities are not good. 4. Due to the reason of low adhesion coefficient, power-weight ratio of steam locomotive is low. 5. It has strictly limited overload capacity. 2. Internal combustion (I.C.) engine drive. This drive is widely used for road transport (buses, trucks, cars etc.). It has an efficiency of about 25 percent when operating at normal speed. Advantage.: 1. Low initial investment. 2. It is self-contained unit and, therefore, it is not tied to any route. 3. Easy speed control. 4. Very simple braking system.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Disadvantages : 1. Limited overload capacity. 2. A gear box is essential for speed control. 3. Higher running and maintenance costs. 4. Operation at any but the normal speed is uneconomical. 5. The life of propulsive equipment is much shorter than that of electrical equipment of a tram car or a trolley bus. 3. I.C. engine electric drive. In an I.C. engine electric drive the reduction gear and gear box are eliminated as the diesel engine is to drive the D.C. generator coupled to it at a constant speed. This type of drive is finding considerable favour for railway work and locomotives of this type are being widely used. Advantages : 1. Low initial investment (since no overhead structure distribution system and equipment are required). 2. No modification of existing tracks is required while converting from steam to diesel electric traction. 3. As the locomotive and train is a self contained unit, therefore, it is not lied to any route. 4. Can be put into service at any moment. 5. Loss of power in speed control is very low (since it can be carried out by the field control of generator). 6. It is available for hauling for about 90% of its working days. 7. Overall efficiency (about 25%) is greater than that of steam locomotives (about 8% or so). Disadvantage: 1. Limited overload capacity (since diesel engine cannot be overloaded). 2. High running and maintenance cost. 3. Higher dead weight of locomotives ; more axles required comparatively (six for diesel electric locomotives in comparison with four for electric locomotive). 4. Comparatively costlier than steam or electric locomotives. 5. In such drives, regenerative braking cannot be used (but there is no bar in making use of rheostatic braking). 6. The life of the diesel engine is comparatively shorter. 4. Petrol-electric traction : • This system, due to electric conversion,provides a very fine and continuous control which makes the vehicle capable of moving slowly at an imperceptible speed and creeping up the steepest slope without throttling the engine. • Petrol-electric traction is employed in heavy lorries and buses.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering 5. Battery electric drive : • In this system the locomotive carries the secondary batteries which supply power to D.C. motors employed for driving the vehicle. • This type of drive is well suited for frequently operated service such as for local delivery of goods in large towns with maximum daily run of 50 to 60 km, shunting and traction in industrial works and mines. • Battery vehicles are sta rted by series-parallel grouping of batteries in parallel for start-ing and running at the speed upto half maximum speed and in series for running at full maximum speed. Advantages : 1. Battery driven vehicle is easy to control and very convenient to use. 2. Low maintenance cost. 3. Absence of fumes. Disadvantages : 1. The major disadvantage of this type of drive is the small capacity of batteries and the necessity for frequent charging. 2. Limited speed range. 6. Electric drive. Here the drive is by means of electric motors which are fed from overhead distribution system. The drive of this type is most widely used. Advantages : 1. As it has no smoke, electric traction is most suited for the underground and tube railways. 2. The motors used in electric traction have a very high starting torque. Hence, it is possible to achieve higher accelerations of 1.5 to 2.5 km/his as against 0.6 to 0.8 km/h/s in steam traction. Consequently, we have the following advantages : (i) High schedule speed ; (ii) Increased traffic handling capacity ; (iii) Due to high schedule speed and high traffic handling capacity, less terminal space is required, this is an important factor in urban areas. Disadvantages: (i)In vincinity it causes interference to the telephone lines. (ii)Whole system becomes standstill in case of power failure. (iii)A very high capital cost is involved for power generation and the associated transmission and distribution.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering Practical: 15
Prepare a report/chart on speed time curves.
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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Parul Institute of Engineering & Technology (Diploma Studies), Limda. Department of Electrical Engineering
Head of the department: Mrs Hetal Prajapati Prepared by: Pinkal Chaudhari st Electrical Engineering, PIET(DS)-1 shift
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