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converting grinder motor with start capacitor from 110 to 220v

Posted by bm_stclair (My Page) on
Sat, Mar 17, 07 at 0:47

Hey all,
I am hoping someone can help me with this. I recently got a grinder/sander. It was set up for 110v but the motor says 110/220v. It worked fine in the 110v configuration but I wanted it to be 220v (heard it was better on the motor) In my ignorance I figured that converting it would be like other tool voltage conversions so I rewired it per a diagram I had from another tool. A little foolish I know, but I didn't have the correct manual and I thought I could figure it out.
What I failed to see and didn't realize was that the motor starting capacitor is rated at 150 mfd and 125 VAC. Anyway, after a brief moment of the grinder running I heard a loud pop and some smoke (i think) coming from the wiring region of the motor.
I then unplugged it and turned it over. The black cover that was on the capacitor had popped off and the dielectric oil from the capacitor was all over the bench and all in the wiring.
The question pertaining to my long winded story is that I still want it to be 220v but I assume I need a different higher voltage rated capacitor. I am just not sure which one to get. Do I need to have higher capacitance as well?
Also is there any chance that I messed up the motor?

Follow-Up Postings:

RE: converting grinder motor with start capacitor from 110 to 220

The motor is fine and all you need to do is buy another cap. of the same value. You also will need to rewire it correctly for 220v-that's why the cap. blew.

RE: converting grinder motor with start capacitor from 110 to 220

There should be,almost always is,a wiring diagram under the cover plate telling you how to wire for 110/220. If not contact the motor manufacturer if possible or post the motor brand and model number and any other relevant info. If someone out there has the same motor, they may have the info for you.The capacitor is only to give the needed boost for starting, then it's no longer "in the circuit"

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