Answer / ajit

it is a protective zone relay it sence the vector
difference between two or more similar quantities.
generally it is current operated .at normal operating time
the sum of Ia+Ib+Ic=0 ,but in abnormal conditation the
resultant current will not zero some current will flow
through trip coil & trip the circuit. most differential
relays are baised current differential current.

why should series motor be started with load and shunt motor should be started without load??????

7 Answers  

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why firewall is build up between two transformer (220/11kv,50MVA)?what should be the firewall height?what is the clearance between firewall and transformer?

2 Answers   Siemens, Tous Stadt,

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2 Answers   L&T,

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what is split phase ac system?

3 Answers   AMIE,

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0 Answers  

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4 Answers  

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1 Answers  

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can we step up dc power using transformer?

15 Answers  

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i have one transformer 1000kva, 11/.433kv. we are using 200/5 amp. ct unit for measuring purpose, & one 800 amp. V.C.B Unit for the same t/f operate, i wants to known the primary current of T/F is only 53 amp. why we used 800 amp. V.C.B ? & 200/5 amp. CT Unit.

4 Answers  

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2 Answers  

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4 Answers  

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what is destructive and non-destructive testing of welding

0 Answers  

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