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determining values for starter capacitors

determining values for starter capacitors

determining values for starter capacitors

(OP)
how do i determine the value of a starter capacitor for an electric motor?  is there a standard procedure/formula?  if so, what is it? thanks!

RE: determining values for starter capacitors

There may be standard designs that all the motor mfrs use but I'm not sure.  The best way is to contact the mfr.  I can tell you that value of the capacitance will affect the torque of your motor.  Also, another rule says to use a voltage of 1.5 x the highest the voltage the motor sees.  The motor mfr may not tell you this.

RE: determining values for starter capacitors

Do a search on this site for more information.

If you have the motor and do not know the size of cap ... post the motor info and I may recognize it!

RE: determining values for starter capacitors

I somewhere read many years ego that a rule of thumb is a 1 KVAR of capacitor for each HP of motor power

RE: determining values for starter capacitors

pcb22000:
My statement about the torque of the motor actually refers to a "capacitor run" motor.  Please pardon my error on that point.

RE: determining values for starter capacitors

Suggestion: It is better to contact the motor manufacturer for a designed or suggested capacitor value since the exact calculation would need motor parameters and curves.
Visit
http://www.iprocessmart.com/techsmart/basictraining.pdf
for motor basics

RE: determining values for starter capacitors

(OP)
just wanted to say thanks to all you folks for responding to my question.  best regards to all of you!

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