Banding and varnish materials

[crafly]

This relates to a thread submitted by shayne31 regarding VPI vs bake and dip. Once again the motor has shorted to ground. I was able to remove a sample of residue and had it analysed as it collected in the motor housing. The results are a Polyester base polymer. This does not relate to any raw materials we use in our process. Is it consistant with materials used for banding and dipping an armature?

 

[oftenlost]

There are still many polyester dipping and VPI resins being utilized. Polyester was the preferred resin in DC armature applications for years as the earlier epoxies tended to crack while some polyesters, like the Vonrol 702 tended to allow flexing without the cracks. The newer epoxies do not appear to have that problem.

 

[powerjunx]

crafly,

oftenlost, had pointed it out. Surely, not the root cause of the failure. There would be a lot of things to point out. try to investigate further.