Slightly Toasted Windings

[rafe]

I have a 220 motor (from compressor) that was plugged in after a long rest (not by me) and it sparked out .....Upon inspection by me ,I have the windings charred in one section for about an inch. I'm just wondering if any one has had any success repairing such a thing....There are some string bindings and they have burned off . I'm wondering if I could varnish the area ?? Just hate to scrap it. Thanks

 

[Mac1]

You are looking at a rewind by some one who knows how. I would price a new motor.

 

[Ulma Doctor]

if you were to disassemble the motor and assure that you could insulate any uncovered section of wiring, i'd give it a go.
you could test the windings in order to see if the windings are open(broken) as well as test them to ground.
the windings are isolated from the motor case, any continuity between the winding and the case will cause failure of the winding.

 

[RJSakowski]

Chances are you will have a short between adjacent windings. However if you want to try to salvage the motor, try submerging the windings in a bucket of varnish. If you can, pull a vacuum on it to pull any air from the windings. Any critical mating surfaces can wiped clean and washed with thinner before the varnish hardens.

Good luck!

 

[brino]

I have chased such repairs and in my experience, unless you identify and fix the root cause, any winding repair would only be temporary. Checking for windings shorted to frame is easy, but if several loops in one winding are shorted to eachother the resistance change is too small to measure but it means more current will flow and the heat will increase......again.

I truely hate to discourage any repair attempt, but it's likely a full rewind is required.....and that could cost more than a replacement motor.
It comes down to how much (time, effort, money) you want to put into a repair and the cost of a replacement motor.

-brino

 

[Alan Douglas]

Two wires at the beginning and the end of the overheated section are probably touching. If (big "if") you can locate this point, you can fix the motor as long as the windings are not physically loose from the varnish burning away. Modern wire insulation will stand a surprising amount of heat. Loose windings can be immobilized with new varnish. But finding the short can be difficult.