Rockwell band saw motor tripping GFI

Happy Labor Day,
I am working on this 1947 Delta 14” band saw.
I am getting close, just need one more bearing and I thought I was ready to go.
I replaced the electrical source 14/3 wire. Plugged it in and the GFI tripped immediately.
I checked my work, all looked good.
I removed the end shield and cleaned the points. They were pretty bad. I also discovered a chaffed wire. One of 3, there are two sets of 3 wires. See pic.
I taped the damaged insulation assuming that was it. Blew all the saw dust out of the motor etc.
I plugged it and it ran perfect, for about ten seconds, then tripped the GFI.
I haven’t checked amp load yet.
This is a 115/230 ac motor. 1/2 HP, frame is 56. Rated at 7.7 amps at 115 v which is how it is wired now.
Please excuse the improper names I applied to the components, I really am an idiot when working on anything electrical.
I would like to save this motor. I’ll look for more shorts in the mean time.
Do you think it can be saved?

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GFCI can be overly sensitive, particularly with older motors and such. You may not have anything wrong really, just an older motor. Try connecting it to a non-GFCI outlet. If it runs for a short time, I doubt it is a short, though there could be a problem with the centrifugal switch and/or run capacitor.
 
The contacts are as good as I can get them. They made contact over about half the diameter/mismatched. I filed and bent it straight.
I’ll try a different outlet.
What is the best way to measure amp load/draw. I know how on a 3 phase but......
Thanks
 
I had an electric an opener that regularly tripped the GFCI. Switching to a different out, no problem. I replaced the GFCI socket which solved the problem.
However, the purpose for a GFCI is to detect small leakage currents to ground which could mean that you could have an intermittent or high resistance short to the motor frame. I would suggest connecting to another GFCI outlet. If the outlet trips, you would most likely have a problem with the motor. If it runs fine, replace your suspect outlet.
 
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I tried a non GFI outlet and it works!,
Ah, it changes direction though. Clockwise, then counter clockwise. It seems to struggle a bit then takes off.
Ideas?
 
I measure current draw with a clamp on ammeter. It works on single phase or three phase. They are very reasonably priced at HF.
 
I noticed a wiring diagram on the side plate. I’ll check to see if it is wired according to the plate for 115.
 
If you have a clamp on ammeter, place the clamp around one of the wires coming into the motor, preferably the load wire. It can be anywhere in the circuit as long as it is a single wire. If you have an inline meter, you will have to disconnect the load wire at some point and rewire through the ammeter.

An easy way to do either is to wire up a duplex socket with a plug ( an old computer cable is a good candidate). for the clamp on, place the clamp around one of the leads, preferably the load wire, and for an in line meter connect the load wire to the meter and another wire from the meter to the outlet.

BE CAREFUL! 120 volts has a bite at best and can be lethal at worst. Make all your connections and stand back before you apply power. If youo are by any measure uncomfortable with doing this , it would probably be best to take the motor into a motor repair shop.
 
Couldn't he Ck the wires for short , by touching each one while searching for continuity . Wires each one and the probe to one and motor . If there's continuity there's short . Bad wire found
 
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