Answer / santhosh (sggi)

Insulation failure of machine coil due to over load,
It can be prevented by using better cooling arrangements
and overloads.

Answer / chand

most common reason is failure of coil insulation due to heat and ageing factor.

Hi, I've just got into my electrical engineering course and I need some help with a question of mine here. During a site visit, we were shown a main LT panel which has switchgears, ammeters and different kinds of relays and the distribution network from that panel. In the main LT panel I've noted down the current readings as Ir - 163A, Iy - 150A and Ib - 147A. The Line to Line voltage is 415 V at 50 Hz and Line to Neutral voltage is 230V at 50 Hz. From the above details, how would I calculate the kVA rating of transformer? The primary side voltage of the transformer is 11 kV and the secondary side voltage is 415V and the frequency is 50 Hz.

2 Answers  

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when running 2 nos 450kva dg sets in parallel operation ,in one Dg set power factor and Kvar going to lagging and ampere suddenly going high,please give me suggestion to correct the same.

2 Answers  

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Transformer how to maintaince a check b check c check d check

0 Answers   DIC India,

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what is the purpose of vector group in a transformer ? if 2 tranaformers r connected in parallel the vector group is same or not? for parallel operation 2 transformers of different manufacturers maintain same vector group or not?

3 Answers   Orchid,

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diff. between star, delta connection?

4 Answers  

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present we are having 0.8pf but I want increase it up to 0.99 so what is the formula for it and how can i calculate?

3 Answers   ABB,

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What is A.C Resistance for Earthing ?

2 Answers  

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what is difference between tension tower and suspension tower?

8 Answers  

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why two contacts(in series) are using in closing circuit

3 Answers  

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if a train is running on a speed of 40 K MPH and crosses a individual passing by him in 48 secs who is riding a horse with a speed of 25 K MPH. what is the length of the train?

2 Answers  

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what deffrence between KW $ KVA ?

7 Answers  

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What is the tolerence limit between neutral and earth in 230 V AC System?

7 Answers   NTPC,

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