Generator brush assembly melted! Cause or effect?

[teneicm]

Hello all-

Our 4.5 kW NorthernLights genset (M643) stopped producing AC power the other day. Some troubleshooting led to a a lack of continuity to the brush assembly. When I pulled the brush assembly out, it was obviously melted a bit and the brush itself was locked into place, which probably resulted in it not making contact with commutator- hence no AC.

The big question is: What caused the melting? Did something get caught or bound up and friction melted the assembly? Or was the heat coming from electrical resistance... Which might indicate the melted assembly is just a symptom of a different issue? The commutator ring seems to be in good shape.

Any thoughts are appreciated!

Cheers- Matt



https://scontent.fkul4-1.fna.fbcdn.n...44&oe=5CF218AD

[coopec43]

I can't help you but maybe a few clues here?

DC generator brush problem. - Electric motors & generators ...
https://www.eng-tips.com/viewthread.cfm?qid=365840
Jun 3, 2014 - 9 posts - ‎5 authors
I have a DC generator which keeps defying our maintenace team. ... Are there burrs, melted portions of the brush box causing free movement of the brushes? ... There was no play in the brush boxes and the replacement parts .

Onan 5500 Generator brushes melting housing... - iRV2 Forums
www.irv2.com › ... › RV Systems & Appliances
Oct 19, 2017 - 14 posts - ‎7 authors
It's the lower brush that over heats or arcs/melts to the housing. I found a ... Is this the first time brush replacement for this generator? Or is the ...

https://forum.carvewright.com/archiv...p/t-28818.html


Clive