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Motor Start Capacitors

Motor Start Capacitors

Motor Start Capacitors

(OP)
How close does the farad rating of a Motor Start capacitor need to be to the original one used with the motor.  Can you bump up the capacitor to help with heavily loaded motors?

RE: Motor Start Capacitors

I would not exceed 20% of existing uf rating and not to exceed 3 seconds. As you add more cap u increase the heat generated by the start winding. Why don't you increase the uf in 10% increments and keep checking the amp draw. Also pose your question to the the electrical motor section on this web site

RE: Motor Start Capacitors

We have an Air Conditioning unit with a Benshaw soft starter.  Last week when I turned on the breaker (not the start control) the SCR bypass had a huge arc, which melted the bypass contacts.  I had the manufacturer rep. come down to do the troubleshooting and repairs.  He megged the motor, ohmed the SCRs and gates and replaced the one bypass that arced.  Upon turning on the breaker (not the start control), the soft starter blew again.  This time burning out the pulse transformers (all six) on the power circuit board (trigger board).  Any info., as to what may be the cause of this problem is greatly appreciated.

RE: Motor Start Capacitors

Sorry, I post my question as a reply rather than a new thread.    
Pls. disregard.  

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