Electric motor smoking

[Rekusu]

What ho one and all,

I have an electric (drum type) garden shredder that recently stopped working. Found the problem was the starting capacitor, which was been replaced and it almost works again.

Almost, because the forward / reverse switch does not always send the drum rotating in the correct direction. But when it works, it is fine, until....... smoke starts coming from somewhere.

Although I bought a replacement shredder, I decided to investigate. Obviously, the smoke was coming from the winding and there is probably something untoward on the inside, which I cannot see. What I can see, is grease from the reduction gearbox has accumulated around one part of the winding, certainly causing the string bonding the winding in one section to melt. I have clean the grease as best as I can and reassembled but yet to test with electricity.

So my questions; can grease cause the winding to overheat and smoke? Could this have caused the lacquer to 'melt' from the inner part of the windings and hence cause a short? Is there a way to clean the grease from the windings as it has probably gone into the inner core of the windings.

Thanks in advance and toodle pip

Rex

 

[bernardgreen]

So my questions; can grease cause the winding to overheat and smoke?

Very unlikely, most probably the motor windings overheated due to over current when power was applied but the motor was not rotating.

A rotating motor generates a voltage opposite in polarity to the supply voltage and hence the current is reduced.

I suspect the capacitor is a run capacitor ( rather that a starting capacitor ) which generates an out of phase current in one of the two motor windings.

 

[Rekusu]

Many thanks. You are probably correct regarding the capacitor. Rookie mistake!

Cleaned it up and tried again, but since it blew the fuse, take it to the 'recycle' centre. Can't be bothered to waste more time on it. Such is the consumer world in which we live.

 

[Lower]

Electrical appliances run on smoke. Once the smoke escapes, they don't work.

 

[Rekusu]

Very good!

 

[bernardgreen]

try Nicotine patches, may stop it smoking......