I've got a fault on a fanuc ac spindle drive model A06B-6044-H018 control board A20B-0009-0532 on an okuma lb15 lathe the error code says that its "Radiator for power semiconductor overheat" lights up as soon as the mains are switched on. I'm curious as to how the drive senses this I'm assuming a thermistor on the heat-sink, I'm making an uneducated guess that the sensors faulty as the fault kicks in from a cold start. Do these drives use any other methods of sensing for this type of fault maybe fan trigger ect?
Regards
Karl