Answer / sangay dorji

soft starter starts the motor slowly at some point and
keeps the speed of the motor constant from that point,
where as variable frequency drive controls the speed of the
motor with respect to frequency.

Answer / m.aqeel

in soft start we control the flux by taking v/hertz ratio
same.
flux directly propotional to v/f
and diffrence between vfd and softstart is only that in
soft start we just control motor in startion and in vfd
case we control motor at any time starting stopping etc

how do we calculate cable sq mm size,that if 50 A load

2 Answers   GTL, PowerTech,

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A synchronous motor is operating at a leading power factor .if the applied voltage is decreases ,(the excitation remains constant ) ,the motor current a)increases b) decreases c)remains same d) none of these

2 Answers  

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Iin ESP why positive is grounded ? why not negative ?

0 Answers  

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how to can we synchronize different capacity of DG sets.60kva& 250kva?

2 Answers   Power Plant,

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why we use capacitor in lighting fixer

2 Answers  

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WHAT IS DIFFERENCE BETWEEN PHASE CONVERTER AND VFD

1 Answers  

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megger generates D.C. voltage while earth tester generates A.C.voltage is it true? I know for megger it is D.C generator but what about earth tester?

4 Answers   IOCL,

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Can we use all 3 cores of a cable to connect DC motor + ve terminal and similarly one more cable for - ve terminal.

2 Answers  

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ROC converges if pole and zero lies inside a) origin b) z=1 c) pole d) zero ? Explanation please? if ROC does not converges then?

0 Answers   CCP,

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what is the thumb rule for determination resistance of resistor?

0 Answers   Siemens,

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tell me about xlpe cable?

1 Answers   IOCL,

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What is the basic principal, by which DC voltage level is increased more than the supplied AC voltage during conversion. As upto AC level it is contorrled by firing anlge but after maximum level how is it possible.Please clear picture. OR we have to supply the higher level AC?

0 Answers  

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