jbcapacitors blog

Keywords: motor run capacitors; motor starting capacitors

You can test a motor run capacitor using a 100 watt light bulb and a digital ac volt meter.
Never use an ohm meter to test a motor run capacitor. It is a very inconclusive test and only shows that there is "something" in the circuit. You are essentially "shooting blind".
To test motor start capacitors you will need a 200-300 watt bulb depending on the size.
Caution: capacitors can hold a charge when removed from the circuit unless they have a bleeder resistor. Discharge the capacitor through the light bulb before handling. A capacitor in a working motor circuit cannot hold a charge, it is discharged the instant the power is removed.

Pls. see our JFS--Motor starting capacitors, here is datasheet: http://www.jbcapacitors.com/pdf/JFS-Motor-Starting-Capacitor.pdf. you will find the quality is quite good when you use the correct test mothod.