On 10/14/2013 9:24 PM, Bill Leonhardt wrote:
....

The shop is in my basement and I believe that general circuits
(thosenot dedicated to a specific use) are required have a GFCI.

If you're covered by NEC in current area, theoretically that's
so...another case where the cure is worse than the disease in many cases.

....

I will see if I can get compressed air into the motor (although I
think it's sealed)to further blow it out. My 13" Rigid planer ran OK on
one of the circuits since I got enough of the board flattened before the
jointer quit to plane both sides.

I'll report back after the air trial.

An potential alternative that fixes the problem longer term if it turns
out the motor leakage has gotten high enough for even a replacement GFCI
would be (presuming it's a dual-voltage motor) to switch it over to a
240V circuit--they're not under the NEC mandate. I'd prefer it on the
higher voltage anyways if possible.

Again, don't forget to check motor connections at the plug and motor end
to ensure they're as clean and tight as possible to eliminate any chance
of a higher impedance connection being the final straw on the current
imbalance.

Since you're hitting both circuits, it's pretty clear the cause is the
motor/wiring there, not the rest of the wiring altho again it's the
total so a little here, a little there, it all adds up...but that both
circuits cause it pretty much rules them out.

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