I get given a lot of brush-motor tools that are "burning', as well as assorted other damaged electrical items. I'm not an electrical engineer, just a fiddler with some background in physics. Now, Jim Hardy and Tom.G have just walked me through testing a 12V alternator, which was found, as far as I can see, to have shorted/low insulation stator windings. I bought an old Megger from eBay for the purpose. If I see a "burning' brush motor tool again, what tests can I do on it? The Megger found shorts between the phases on the alternator, but how do you test a single phase motor for a coil short that is not to ground - a ringer? The same question applies to transformers - if the short is not to ground, what test gear will find it? In other words, I have a multimeter, scope, bench power supply, ESR meter and a Megger insulation tester. What other gear do I need to fully test appliances found in the home and workshop?