I have a late 80's LC40 with two turrets and live tooling and a tail stock. When I got it the smaller turret would not move in X, only Z... and the former owner told me the Okuma techs came and said it needed a new servo driver board, but he never used the 2nd turret so he never fixed it. I looked at noticed the two red lights were lit up on one of the servo drivers in the back.

Since then, I noticed the lower turret will not move in Z now... and when I was looking in the cabinet, I noticed 3 out of the 5 servo drivers have two red lights on. It seems something is dying over time inside the drivers.

I am guessing it is the big transistors (or are they thyristors or IGBT's or something?). But I don't have a manual for the servo drivers.


1) Does anyone have any manuals for the LDU-600? Schematic, repair manual or anything? I don't even know what the 2 red lights mean (marked IOC and P.H.).

2) Anyone fixed one of these before? I am guessing it could be caps on the main board of those "power module" things. Those modules are labeled PDT2510... they were made by International Rectifier but that part number doesn't show up anything. If I could find a datasheet, I would be able to cross-reference with a modern part. Anyone have any knowledge on these?

Thanks!