Ladies and gents.

We have a Kitmura Minisuper-300 ( Mycenter 0) with a Fanuc 0M controller. The ac spindle drive ( A16b-1100-0090 ) ( analogue ac spindle model H002 ) fan failed and the Fuji a50L transistor module burned out. Looks like it took all the transistors and the whole firing PCB with it. Currently the spindle gives Alarms 12. We replaced all the ET191 transistors , bloated capacitors, diodes, the a50L Fuji module , but still burning out.. The voltage on the P+ N is 290VDC , the voltage coming from the PCB is 45VDC on the transistor side( seems way out ) While testing the leg A, the ET191 transistor burned out again. I've read some posts on the alarm 12 error, however most of the components that we've changer didn't make the final cut. Please advise on voltages, and components that we should be looking at to rectify this problem.
( any literature , voltage params, etc are more than welcome )

thank you kindly