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LOCO SHED GOMOH

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ACKNOWLEDGEMENT I would like to express my sincere grateful and profound gratitude to LOCO SHED ,GOMOH for providing an opportunity to undergo Vocational Training of 04 weeks in “ELECTRIC LOCO SHED, Gomoh, Jharkhand’’. I bear immense pleasure in expressing my gratitude and thanks to all the Employees of respective shops for their honest teaching, practical demonstration, guidance and suggestion in respective sections. Furthermore, I would like to acknowledge with much appreciation the crucial role of staffs, who gave us the permission to use all required equipment and the necessary materials during our training period. CONTENTS 1. Introduction 2. Locomotives 3. Syntaxs used in Loco 4. Components of Loco 5. Different Sections of Loco 6. Brake Rigging 7. Pantograph 8. Traction Converter 9. Working of Loco 10. Conclusion INTRODUCTION  The ISO-9001-2008 certified Electric Loco Shed, East Central Railway, Gomoh situated in Gomoh. ELECT...
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Hot wire instrument

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                    HOT WIRE INSTRUMENT MAIN PART:-   (1.) Platinum- irridium wire, 2. Thread, 3. Pulley, 4. Spring WORKING PRINCIPLE:- It works on the heating effect of current. WORKING:- As an ammeter it is connected in series of the circuit. The current to be measured is passed through the platinum- irridium wire. • The wire is stretched between two terminals. • To this fine wire one more wire is attached at one end and to the terminals at the other end. • A threat is attached to the second wire. • It's arrangement with pulley and spring is shown in figure (a.)      figure (a.)   Hot wire instrument DEFLECTION:-   When the current is passed through the fine wire due to heating effect      ( directly proportional to I^2 R) it gets heated and hence expands. • The sag of wire is magnified and hence expansion is taken- up by the spring. • This sets- up the motion of pulley. Pul...
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Moving iron instrument

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                   Moving iron instrument    • Most common form of ammeters or voltmeters for use in laboratory etc. Are moving iron type. They can be manufactured at cheaper cost and the required accuracy can be obtained. • There are two types of moving iron instruments. (1.) Attraction type (2.) Repulsion type (1.) Attraction type:  It consists of a fixed coil C of insulated copper wound on the bobbin and an iron disc D. The current to be measured ( or a current proportional to the voltage to be measured ) is passed through a coil of wire , the number of ampere turns are required for the operation of the instrument and this number can be made - up by having few turns and large current or vice versa depending upon whether it is a ammeter or voltmeter . In this form of instrument , a small piece of iron is drawn into the core of the coil when the current flows. Figure. (A) Whatever be the direction of the curre...
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Permanent Magnet Moving Coil

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Permanent Magnet Moving Coil:- *Advantages of permanent magnet moving coil instruments:- (1.) Very small power is required for its operation. Hence,  power consumption is very low. (2.) Torque to weight ratio of movie system is high. (3.) Scale is uniform and long scale is obtained. (4.) It can be used as a ammeter or voltmeter only by using external resistances. (5.) It is free from hysteresis error. (6.) Error due to stray magnetic field is negligible. (7.) Eddy current damping is used to without any extra damping mechanism. (8.) Strong operating magnetic field due to permanent magnet and iron core arrangement. * Disadvantages of permanent magnet moving coil instruments:- (1.) With time the strength of permanent magnets reduces, causing error in reading. (2.) Thermoelectric e.m.f may cause errors when it is used with shunts. (3.) Costly. (4.) Can be used on D.C only and not on A.C. This is because the direction of magnetic field due to permanent magnet is fixed. And if the direct...
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CAPACITOR

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CAPACITANCE:- 5.1. Capacitor A capacitor essentially consists of two conducting surfaces separately,vy a layer of an insulating medium called dielectric. The conducting surfaces may be in the formof eithercircular (or rectangular) plates or be of spherical or cylindrical shape. The purpose of a capacitor . is. to store electrical energy by electrostatic stress in the dielectric (the word 'condenser' is a misnomer since a capacitor does not 'condense' electricity as such, it merely stores it).BA parallel-plate capacitor is shown in Fig. 5.1. One plate isjoined to the positive end of the supply and the other to the negative end or is earthed. It is experimentally found that in the presence of an earthed plate B, plate A is capable of withholding more charge than when B is not there. When such a capacitor is put across a battery, ~ere is a momentary flow of electrons from A to B. As negatively-charged electrons are withdrawn from A, it becomes positive and as ...
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Moving iron

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               MOVING IRON :- my personal notes * moving iron  instrument :- ° Definition:- The instruments in which the         moving iron is used for measuring the flow     of current or voltage is called moving iron       instrument . ° it is most accurate instrument is used for      both A.C & D.C measurement. ° there are two types of moving iron                   instrument. (1.) Attraction type (2.)           Repulsion type.   picture no:- A(चित्र- A) (1)Attraction type Moving iron. °Construction:- attraction type of moving iron instrument the stationary coil of the attraction type instrument is flat and has a narrow opening. The moving  element is the flat dise of iron core. The current flow through the stationary coil produced the mag...
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