Answer Posted / rabi

Ac-1 contactor is used for "Non-inductive or slightly
inductive loads, resistance furnaces".

Ac-3-contactor is used "Squirrel-cage motors: starting,
switching off motors during run-ning."

what is meant by directional earth fault and non directional earth fault? describe both.

1840

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Why it is necessary to isolate fire fighting when you are taking shutdown for lv board.

1582

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What is core CT & it's function?

2104

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Why does the speed regulating system adopting I controller have no steady-state error? In this single closed-loop speed regulating system, when the input of the I controller Un=0, what is the output voltage of the regulator? What factors do the output voltage depend on?

1816

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Q: How to calculate Transformer losses , tell us by Formula.

1994

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how to select electronic timer(Star-Delta) setting for diff. rating motors

1907

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What is the difference between relays and contactor construction wise?

2154

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Determine the BTU size of an aircon for 20 sq metre room

1819

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and gate circuit diagram,amplifier circuit diagram

2019

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What is the alternate solution for testing of polarity by using polarity tester while its milli ammeter does not works?

1981

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In case of HV test on medium voltage cables, BS is asking for 4 U0 where as IEC is asking for 3.5 U0. Can any one advise me how this 3.5 times or 4 times U0 is derived?

1643

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I have a relay contact rated at 220v dc which is supplied with a 24vdc from the panel,for it to trip the dampers(24vdc).What if the application of the relay changes so that it should work at its rated 220vdc then will it work at 24vdc supply given or any other consideration needs to be taken .....

2017

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What is called grain-oriented laminations?

1076

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Whar is the KvA rating of 33Kv substation & actual kv rating of power generaating station.

2333

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How do apply electrical 'c'license......pls advice

1640

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