Fresh out of repair I hooked up my IGBT pack for testing one channel. I had vaporized some traces off the secondary supply voltage. I hooked up the load, the low voltage drive and then my best guess on the isolated power supply. I guessed wrong. I was hoping because the Chiller had a good 4 or 5 24VAC secondary transformers and 24VAC is ubiquitous throughout the HVAC world. I guessed wrong. I let some more smoke out.
I am lucky I have a new friend who works on Chillers. He hooked me up with the water-cooled heat sink and I have a pump and some capacitors coming to me as well. I’m going to ask him to let me poke into an operating board with my multimeter next time we are working together to find out whats going on. The pair of wires is feeding 6 isolation transformers in parallel with what I thought were MOVs but it’s hard to tell, no markings and I doubt my soldering skills could get them safely off and back on again? Maybe…
Well back to the drawing board… rumor has it they might have another (smaller) drive out of a refurbished unit…. could I be so lucky?
