05-04-2017, 09:49 PM
It's been my experience that it's usually the high voltage winding that fails on a power transformer, but you can usually find this out by measuring the resistance between each leg and the center tap of the HV winding, they should be pretty close to equal, like within 20 Ohms. If it's more then that then the HV winding may have shorted turns, which will cause the transformer to get hot even without a load.
Regards
Arran
Regards
Arran