what is the pressure of vacuum circuit breaker

can anybody tell me that for p.f. Improvment we use capacitor banks but how to decide its capacitance. As we all know how to calculate kvar but what abt capacitance value

0 Answers

How do you protect your appliances from harm in case of neutral failure in a three phase power supply set up.

4 Answers

Two electronic energy meters are connected to seperate phase wires, but connected to a looped neutral. Are these going to function correctly?

8 Answers DRDO,

Any one can explain if there is any harm from humming noise heard from air circuit breaker : we have 415 switch board having two incomers from transformers 3.3KV/415V , when bus coupler closed, and open one ACB incomer to work in one of the transformers, the current started hunting around 50 Amps, and heard humming noise from the air circuit breaker, although the load current was only 1200 amps while the ACB capacity is 2500 Amps, and the transformer 1600 KVA. The same didn't happen when taken the other transformer offline. Why this humming noise and current fluctuation? is there any implication or danger, bearing in mind that we just returned everything back to normal and stopped the maintenance of the transformer. Shall we go ahead and ignore this noise?

6 Answers

Why AC current leads voltage in capacitor and how?

0 Answers BMB,

we done magnetic balance test for 33KV /440V transformer in our company , but the ratio out is confusing us Voltage applied in RY = 440 , at RB = 320 and YB = 60 RY 440 = ( RB + YB ) 380 only Please let me know what type of problem is it.

2 Answers

What is the difference between single phase, 2phase, and 3 phase motors?

2 Answers

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