Tapping a 3 phase 480/208-120 transformer

[jscarborough]

There is varnish on the taps on the primary side of the transformer. Do I need to remove this in order re-tap for a different voltage.

 

[jscarborough]

480/208/120 3-Phase 10kva transformer taps. What is the method for getting continuity from the taps over to the primary when there is varnish completely covering the tap?

 

[electrofelon]

Yes remove. Scrape off with a knife or Emery cloth.

 

[LarryFine]

. . . sandpaper, wire brush, flame, etc.

 

[jscarborough]

I thought the removal of the varnish would create heat or a loss of voltage. The correct answer is that the varnish only provides environmental protection from harsh conditions suck as salt or extreme moisture.

 

[LarryFine]

In transformers and motors, varnish is used as the electrical insulation. It allows the conductors to be wound much tighter and closer than a plastic insulation.