Answer / qureshi majid ahmed

The dc motors are not much used in the industrry because we
need every time the commutator to convert internally
generated AC voltage into dc voltage.For large scale
industries we can not accomodate commutator in this range.So
even having robust characteristics,they are not preffered
for large machines

Answer / siva shankar

Presently AC supplly is going on thats y... if we keep the DC motor there we need some rectifiers

Answer / naeem anwar

mostly, industry uses an induction motors for constant
speed as required for your jobs just like paper mills,
variation in speed cause paper broken etc.
secondly, vfd(variable frequency drive )are made mostly to
control different parameters of AC motors.

Answer / apoorv

dc motors are not used because of commutation problems , and dc supply has to be given which require rectifiers at generating end and commutators cannot efficently convert ac generated vtg inside dc machine into output dc vtg.

Answer / yash sharma

if you are richy rich you can afford DC motor.simple

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1 Answers  

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4 Answers   TCS,

I have a small system with two motors that are running on 380 vac, 60 hz. These motors are expensive and I usally get them from Brazil. I am adding another motor to the system, but I want to purchase a 480 vac, 60 hz motor to use. It will be on a VFD that is rated fro 380 thru 480. Is this posible and will I have to use a larger motor and derate it?

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