why we use REF and Differential Protection in one transformers?my doubt is both protections are operated in internal fault only.why we want to use 2 protections?please clarify.

7 Answers  

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How to work definite,over pluxing,revers power,OSR relay

0 Answers   Ford,

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Assume a condition such that two motors of rating 6.6kv,415v are connected to blower,so tell me which motor draw large current give appropriate reason?

2 Answers   NTPC, Student,

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When do you use a VFD motor?

3 Answers  

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what is the iron loss in a 11KV/440V transformer?

2 Answers   Bhel, TVS,

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Difference between Lugs and Thimbles

0 Answers   ABB,

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at which voltage level arcing ground is occurs ??????????

0 Answers   TATA,

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How to calculate ant test the burden of Current transformer

0 Answers   NTPC,

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sir i used 3 hp of motor for spraying pump, other home light and other home items which size of allminium pvc wire ix used

0 Answers  

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while doing the excitation current test on power transformer what is the value of voltage to be applied? Nomonal rated voltage or 10% of rated voltage? Is it necessary to apply on high voltage side?

1 Answers   ACC,

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What is Star Delta Connection, where it is applied & what for it is used

4 Answers   Premium Transmission,

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why single phase to grd test in HV cable?why not 2 phase at a time?

0 Answers  

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