why exterrnal C.T. protection is used even though ACB& VCB is having inbuild C.T. protection?

2 Answers  

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To determine the Healthiness of Insulation we will be performing Dielectric tests i.e Insulation Resistance test, Partial Discharge test,Switching Impulse, Lightning impulse, Tan Delta test ...etc why we required to perform this many test, why cant we do only one test. for Transformer, CT's

1 Answers  

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Why is shaft current insulation required on large motors & when should it be checked i.e. before or after assembly?

2 Answers   Aramco,

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What is min and max voltage between earth and neutral/phase if it perfect earthing?

37 Answers   Epoch, ISS, ITC Infotech, L&T, Power Works, Statex, Sterlite, Wipro,

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Inverter. converter. Ups.MCB.solar.alternators. motors.

0 Answers   Cisco,

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what is the order of mgnetiation current in a current transformer of 1000A/1A ratio?

2 Answers   Power Grid,

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difference between moore and mealy model

2 Answers   Google, IBM, TCS,

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what need of NGR(neutral grounding registor)? What it works?

2 Answers  

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What is the difference between reverse power trip & inadvertant trip?

1 Answers  

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PLZ EXPLIN ABOUT CLASS PS CLASS CT .WHY THEY R DESINED AND FOR WHAT PURPOSE?WHY OTHER CT CANT BE USED AS PS CLASS CT? EXPLAIN IN SIMPLE LAUNGAGE IF POSSIBLE PLZ GIVE CIRCIT DIAGRAM?EMAIL-RAJ_SINGH_0376@SIFY.COM

0 Answers   ABB,

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what are the advantages and disadvantages of speed control of 3 phase induction motor by varying frequency explain with drawing

0 Answers   ABB, Genpect,

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Why breakers not synchronized when the synchroscope is going in the anticlockwise direction?

2 Answers  

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