overload protector tripping

[arnolfini]

I recently purchased a used jet contractor saw and I'm having trouble with the overload protector. It first started tripping a couple months ago when I was ripping some 5/4 hard maple. I figured that I was just pushing the saw a little to much, so I let it rest between boards and was able to finish my cuts. Tonight however, it starting tripping while I was cross cutting some pine, and then it started cutting out with no load at all.

The motor spins freely by hand, and I aligned the pulleys when I got the saw. Is it possible that I have a bad overload protection breaker?

Thanks in advance for your help.

[Bob AZ]

I had a similar problem. I disassembled the motor, cleaned all the bearing surfaces, relubed everything. If you have a motor with ball bearings replace the bearings. And clean everything.

Bob AZ

[George]

Possible. Is the motor hot? That's what the breaker's trying to control. If the motor's hot, look elsewhere for the source of the problem, it's doing its job.

[arnolfini]

The motor casing doesn't feel hot to touch at all.

[seelyjv]

Are you using an extension cord to power the saw? If so, what gauge wire is the cord? If used, an extension cord for a 110 volt 1-1/2 HP motor should be fairly short and of a relatively large wire gauge. Probably at least a #12 gauge wire and no longer than about 12 feet. Jim Seelye

[RayV]

Extension cord is the most likely problem. I had to by a 14 guage cord (wow! $$$) to run my saw until I got around to running a 20A cicuit out to my garage. Voltage drop is very real and can easily burn up a motor.

[arnolfini]

Thanks for everyone's help.

I was able to measure the current the saw was pulling when the overload protector tripped. It measured 10.8 amps, which was much less than I expected. However, the overload protector was quite hot. I ordered a new overload protector from Jet and the saw has been running smoothly ever since.