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Single phase motor controller

Single phase motor controller

Single phase motor controller

(OP)
Would to know the right capacitance rating for a 230v 5hp 21amp motor. I have a controller that too many hands have been in and think the capacitors are sized wrong. I have two 15uf run and two 850mfd start capacitors with no relay on the circuit.

RE: Single phase motor controller

Something needs to switch the start caps out of the circuit. No evidence of this?

RE: Single phase motor controller

Two 850mfd start caps seems excessive, unless they are paralleled up,to help out on the voltage front...
 and yes,,they must be switched out somehow.....is it a series -parallel start machine???
 have you anymore details.

RE: Single phase motor controller

Those sizes are not off for a 5 HP motor.

Odds are the "relay" is a centrifugal switch in the motor!

Is this a control box for a pump?

What is the motor doing that makes you think the caps are wrong?

Specs on the motor and application would be nice too!

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