Answer / gopal agarwal

SURGE arresters are used for arresting i.e. controling
lightining surgs which are accured during clouding.these
lightining surges are of very high voltage ranges such as
many times greater than the rating of equipments ,which will
damage them and hence these are used at both sides end of
electrical equipments for protection.

I am getting above 60 V as open delta voltage against single phase unit ICT at tertiary delta formed and ICT getting trippped on NDR. ICT tested and found in order. PTs provided on tertiary are tested and in order. what may be the reason?

0 Answers  

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When measuring the Insulation resistance of a motor winding (winding to earth) using a megger meter, Applied voltage(1000V) was automatically reduced to 500V. and the measured insulation resistance values are also very low (in Kohm range) Can anyone give me a reason???

3 Answers  

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What happened when voltage will half value of current ...

0 Answers   SCL,

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why is the earthing pin on 3 pin top are big and thick

3 Answers   Marriott,

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if 20 hp motor starts directly delta connection.motor what will be the effect.

3 Answers   HP,

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what is wave trap? And how it works?

3 Answers  

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Explain the working principle of servomotor

20 Answers   ABB, Bhel, FANUC, GE, Jindal Steel and Power, L&T, SIA, Steelco Gujarat Ltd,

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In Energy meter How many rotation Equal to one unit.

3 Answers  

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We have .ht motor which is 60Hz.we run on 50Hz.so that it's speed reduce but we had one prob.that motor winding temp increase up to 135 deg.we want reduce this temp.what to do?we arrange ext.cooling fan but not much effect.we want reduce this temp. Inhouse without affecting much.cost. also don't want reWINDING OF MOTOR?

3 Answers  

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only three phases are coming in step down tranformers.how to get neutral?

5 Answers  

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why potetial transformer primary ground?

1 Answers  

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What is the thumb rule for calculating the P.F correction Capacitor?? Say for 100 hp motor how much micro farad Capacitor is needed .... Thumb rule so quick answer wanted

9 Answers   Bhel, Dubai Group,

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