Hi, several years ago I had an issue with the SDU on my old Okuma LB15. The problem was fixed by replacing the encoder on the rear of the spindle motor. Unfortunately it seems to have failed again. I have sourced a complete spindle motor and replacement SDU from the same model of machine with the idea of swapping parts over. Both components have been in storage for several year and the seller recommended using a variac transformer to bring the voltage up slowly over a period of time. Apparently it can extent the life of the capacitors and reduce the chances of them blowing up. Has anyone heard of this before? Thanks