link1896
Mr Greenfield
I spent hours digging into a Samsung compressors main PCB a few years ago when it failed for no good reason. One large single PCB with IGBT's for compressor motor VFD. Everything was vaporised on the high side of the PCB for no apparent reason. Unit was wired back to the main distribution board on its own breaker, single phase DB. Two other air conditioners in the house, same deal, breakers for each. Nothing else in the house had failed, the UPS for my server rack was set to full logging and alerts, never any notable voltage spikes, quite the mystery. Wired a Lenz single phase 240 in, 240v out VFD to the compressor motor and it ran fine. Completely stumped, ended up buying a new pcb direct from our states master distributor who were amazed I'd gone down to board level