Answer / parthasarathy c

Diffrential protection is used to protect internal fault
like winding faults,it is used to protect the the
equipments like Generator,Transformer and bus bars.

If CT polarity changed in Directional type releys it will
give trip command when normal operating condition.

Brfore giving connection we must read name plate details to
avoid polarity change.

please tell me when we start motor without load in star or delta connection whose current above condition,pl write formula

0 Answers   Foxconn,

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Installation resistance for whole installation of 16 kva & 25 KVA DTRA a) Between each conductor b) between conductor to earth c) installation resistance for each apparatus, each conductor to earth d) earth resistance for the system of earthing

0 Answers  

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how to select a air/vacuum circuit breaker.is there any thumb rule???

1 Answers  

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How to choose primany and secondary side MCB

1 Answers  

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which surface is suitable for NEUTRAL GROUNDING ?

1 Answers   NTPC,

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1000kva = how much kvar

3 Answers  

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directional relay is typically used to respond in fault condition who it can be used just as reverse power protection which purely senes direction reversal to operate a circuit breaker?

1 Answers  

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I have 10 amp MCB for my air conditioner of 1.5 ton capacity. When I connect the ac direct it is started running but when connected through stabliser the Mcb Get trip and air conditioner couldn't start.please confirm whether Mcb is required to be upgraded to 20 amp. There is no fault in ac and the stabliser. Please advice the reason of tripping the mcb when connected through the stabliser.

1 Answers  

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How to convert 2 phase to 3 phase electricpower in induction moter?

0 Answers   HCL,

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at the time of starting back emf of a motor is zero.so how can it will start to run??

1 Answers  

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what is the knee point voltage ? what is differtial rela? what is impedance and % of impedane? what is the postive phase sequance ? negative phase sequane ? and zero sequance impedance ? what is sortcircuit calculaion? why take calculation? define stabilty test ? why? what sentivity test? define merz protection ? what is the burden ? class 5p10, accracy, metering ct take knee point voltage test thet time what heppan why dont take knee point test to metering ct?

0 Answers  

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what is the difference between 2phase & 3 phase?

1 Answers   NTPC,

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