Is a contactor (or master relay) required between incoming lines and a VFD? The question goes to safety. If a contactor were used before the VFD and an e-stop engaged then the motor will coast to a stop (i.e. VFD loses power) instead of stopping much faster if the VFD braking fucntion were used. It would make more sense to keep power on the VFD.

0 Answers   Pride Hotels,

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why permanent magnet generator have higher frequency of 400hz

3 Answers   Jaypee,

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what are FM 200 systems? why it is useful for electrical systems ?

3 Answers  

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Advantage of earthing transformer

2 Answers   EID Parry,

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what is the difference between ac drives and dc drives?

1 Answers  

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What is the formula of frequency ?

0 Answers  

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define transformer

1 Answers  

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what is the problem in manufacturing transformer with 0 degree phase displacement.???why alwasys go for DYn11 or DY5?Whys not DY0 i.e zero degree displacement between primary and secondary side vectors?

3 Answers   Bhel, dpdc, Prime Electrical,

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1. What are the tests to be carried out for CBCT? 2. can measure the secondary resistances? 3. with respect to secondary maximum how much voltage can be applied for IR test.

0 Answers  

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why do we have spikes enough to burn electronic boards, when generators are not grounded

0 Answers  

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400Kv,can it be generated?why?

2 Answers  

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Upto what extend the powerfactor of a supply system can be improved to be cost effective?

1 Answers  

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