Why dc supply is used for closing and tripping coil of ht breakers. What happen if we use only ups ac supply only.

12 Answers   ACC, JLL, ZETDC,

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how we can select a transformer based on a particular load. suppose we have 4 motors of rating 40 h.p , 50 h.p, 80 h.p & 100 h.p. then what rating of transformer we can select. urgent. pls reply

6 Answers  

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how dia of wire and angles are calculated for overhead shielding wire to protect substation equipment from lightening strokes???

0 Answers  

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Do anyone know how can I calculate earthing for substation or do anyone know any software which I can use for this case

1 Answers  

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two 100W/230V bulb are connected in series. what would be the voltage drop across 1 bulb

6 Answers  

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for 8 mva 33/11 kv transformer what will be the setting of differential relay on which it trip & what is the HF setting in this relay

2 Answers  

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I have 800 Amps MG Fix type breaker It is in on line & it has been given only UV (under voltage)coil connection for tripping purpose.now it is not working properly means its getting tripp so how can i replace it or how can i rectify the problem without destrubing my load??????????

2 Answers  

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why did youi choose this career?

0 Answers   KTB, ONGC,

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1.Can we use 6.6/11KV 300sq mm xlpe 3core cable for LT use (415 Volt). 2. If we use it for LT then what is the current rating

0 Answers  

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One VFD is possible to connect two motors at the same time?

2 Answers  

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why C.T secondary are rated 5A generally?

13 Answers   ABC, Bhel,

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what happen when power factor of 2 parallely operated transformer become equle?

0 Answers   Flextronics,

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