1. name the relay for protecting transformer 2. Current Transformer 3. potential Transformer

1 Answers  

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How to control motor gearbox speed and friquency? If length of cable and dia given, how to measure the voltage drop?

0 Answers  

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how much earthings are mendatory at a 25kva sub station?

3 Answers   Bhel,

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In power plant synchronizing time (synchroniging meter should be 12'o clock position only. why not 6'o clock position not possible.

1 Answers   ITC Infotech,

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What is the test block protection relay if any body know plz explained

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What is meant by reactance voltage?

0 Answers  

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capacitor is load free component but why ampare meter shows current when capacitor bank breaker close?

5 Answers   Bhel, OPS,

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-----------means a source which can supply a constant voltage to aload irrespective of the valu of load resistance.

2 Answers  

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My question is whether bellow formula is correct to find bus size for 46kA for 0.5 second & what is RT in bellow formula. formula to calculate the size of busbar to withstand the thermal stresses due to currents with duration of 0.2 sec to 5 sec. Sp = RT( I x I x t) / K Where Sp – is the cross sectional area of bus bar in millimeters. I -    is the value of AC fault current. t -    is the operating time of disconnecting device in seconds. K –  is the factor depending on the material of the conductor, insulation and initial and final temperature. Value of ‘k’ for copper is 143.

0 Answers   Premier,

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What are the common sources of energy?

0 Answers  

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how is choose &depending upon the load why?

1 Answers   HCL,

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why the excitation is necessary to produce the reactive power

2 Answers  

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