what are frequency changers ? Tell me about commertially availble frequency changers ?

1 Answers   GE,

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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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if you are in a software company,then why do you want to come in a core company like sail, ntpc(where lots of trouble like tension but you have a good life in a it company) ?

0 Answers   Sail,

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what do you mean by PF correction. A motor is rated at 15 kw,415 volts, 0.7 pf and eff of 0.92. The powerfactor is improved to 0.98 by adding capacitors at the bus. calculate the current drawn by motor under full load condition before and after pf correction

5 Answers  

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whye the current increases in the motor when the load on the motor increases

3 Answers  

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i have one source transformer with the capacity of 50KVA, connected with two loads 10kw and second one is 15kw.. how can i calculate first load in KVA and second one in KVA .. because Kva rating, power factor rating of of transformer is different from the load… there must be some way to calculate load KVA rating and power factor….

1 Answers  

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How to check the efficiency of the generator , air compressors.

1 Answers   CIL,

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what is the soft starter principle? how is connection diagram? what is the procedure for checking the connection?

0 Answers   Siemens,

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Why converter duty transformer neutrals are not earthed...i am still not sure if this question is also correct...Please email at ranjan120482@gmail.com

0 Answers  

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what is linear motor?

2 Answers   Lucas TVS, wbsedcl,

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what is the difference between electrical and electronic choke?

0 Answers   TCS,

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from which formula we select a capacitor rating?

4 Answers   Suzlon,

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