Answer / linu mohan

RELAY CODE NO.-32
DIRECTIONAL POWER RELAY

Answer / sanjay d. dabli

DPR IS DIFFERENTIAL PROTECTION RELAY & IT IS USED FOR FAULT CURRENT PROTECTION.WEATHER IT MAY EARTH FAULT OR PHASE TO PHASE FAULT. IT'S NO IS 64.

is it necessary to earth the rmu before cutting off the transformer winding?if yes why?

0 Answers  

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why 3 phase induction motor only need starter ? why not other motors need starter ?(like synchronous motor,single phase induction motors & their types) ?

3 Answers  

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what do you mean by earth fault in transformer?

2 Answers   L&T, UPL,

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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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when we are going to higher voltage level in substations why we are using Sf6 circuit breakers instead of Vacuum circuit breakers.

3 Answers  

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How to calculate the Harmonics losses in terms of cost/unit.

0 Answers  

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Advantages of Induction Motors

2 Answers  

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aternator every parts and its working

0 Answers   adag,

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How to test Alternator stability test for REF relay

0 Answers   Amprotec,

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Explain the terms real power, apparent power and reactive power for ac circuits and also the units used.

0 Answers  

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how to check capacitor in general

1 Answers  

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What is FM200 Fire Supresion System??

3 Answers   Emerson,

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