please send me previose rrb junior engineer qustion papers

0 Answers   RRB,

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Whether the LIGHTNING is AC or DC?

9 Answers   Bhel, IEEE,

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What is switch gear? How it is work ?

1 Answers   AbaQulusi Municipality, Lupin,

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will aqatic animal die if we ground the wire of three phase instead of grounding to earth

2 Answers  

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Why mostly GT(Generating Transformer)has only Ynd1 Vector Group?

1 Answers   Essar,

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What is the polarization index value ? (Pi value)and simple definition of polarization index ?

0 Answers  

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What is meant by positive and negative feedback?

0 Answers  

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I want to know Electrical Circuit?

0 Answers  

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why 30 ma elcb is used ?why cant 100 ma?

3 Answers  

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I have carried out wiring for lighting in a shed in Industrial area which contains Metal halide lamps & have balanced in 3ph.Now when we put all the lines on in the daytime the current taken at 3phases at MCB comes to be equal i.e.28,29,28Amps respectively but in the night time i.e between 7p.m.to 11p.m. at the same MCb the current is 52,59,62Amp, though I have fit 63A MCB it is tripping in the above period.What may be the reason.? Note: This industry is located in industrial area where majority of steel ingot manufacturing plants are there. Whether this may be due to harmonic? what should I do to overcome above problem.pl suggest urgently.

4 Answers  

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What is method of calculating the fault current for a MDB, 50KW, 3PH, 415V, 50HZ?

0 Answers   L&T,

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How will you justify IR value and Charging voltage of any motor,transformer and Cables.......???? . . . . . . . . Plz tell me any body Baljeet Singh, engineer_89@refiff.com

0 Answers  

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