Last week I was doing a chucking job on a mori seiki sl15 with a fanuc 10tf control. Almost through with the job. Put a part in, closed the collet, and pushed the cycle start button....nothing. couldn't get an alarm number on the crt at all. I opened the cabinet and there it was, the dreaded AL-12. I sent the fanuc spindle drive to a repair facility to have it gone over. I got it back on Thursday (quick service) and installed it yesterday. Double & triple checked the wiring to make sure it was correct. I flipped the breakers on the main panel, then flipped the power switch on the end of the machine. The hydraulic pump and cooling fans came on, then I pushed the start buton on the control.....good so far. When I released the e-stop button, the machine shut down and tripped the 50A breakers in the main panel. I pushed the
e-stop, turned the machine off and reset the breakers. When I turned
the main switch back on I get AL-4 (fuse blown).
Any thoughts what might have caused this?

Thanks,
Martin