Three of the P4 50kw boards booted up without issue. Their next step is to be test driven along with some other boards.

The 4th P4 50kw board has an issue with IGBT driver #4, so it’s faulting. Disconnecting the IGBT driver allows the board to boot fully.

The 5th P4 50kw board squeals when powered up. Been down that road before.

The 6th P1 50kw board has a crater in the middle of the Mach220. I’ve de-soldered a few of the 68 pin Mach220’s and put down surface mount sockets, but there could be some toasted traces too since it took so much power to damage that chip.

Powered up one of the 65kw boards. They use the J1850-VPW bus for communication, so I could not watch the activity on Buscom without a J1850 to RS232 converter. Plenty of these on the market to fix that. More than a level shifter is needed here apparently.