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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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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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ZENER DIODE AND TRANSISTOR

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ZENER DIODE A zener diode is a special type of diode that is designed to operate in the reverse breakdown region. An ordinary diode operated in this region will usually be destroyed due to excessive current. This is not the case for the zener diodA zener diode is heavily doped to reduce the reverse breakdown voltage. This causes a very thin depletion layer As a result, a zener diode has a sharp reverse breakdown voltage Vz This is clear from the reverse characteristic of zener diode that the reverse characteristic drops in an almost vertical manner at reverse voltage Vz As the curve reveals, two things happen when V is reached: The diode current increases rapidly. (i) The reverse voltage Vz across the diode remains almost constant. In other words, the zener diode operated in this region will have a relatively constant voltage across it, regardless of the value of current through the device. This permits the zener diode to be used as a volage regulator For detailed discussio...
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