01-17-2015, 03:51 PM
Well, you can test a transformer when it is "out of the chassis" by hooking up the primary wnding, and carefully testing all the secondary windings. Your high voltage readings should be just about equal compared to the center tap. Hooked up this way with no load, there should be little if any heat build up. Additionally, most (but not every transformer) does not have any windings connected to the shell.
