Hi,
I have a Niigata horizontal machine with Fanuc 15, the problem is that the Y axis motor is getting hot after a few hours and stop the machine with SV001 alarm. There is no counterbalance on this machine.

I took all the servos out and cleaned the fins (lots of mud) changed the fans on the power supply and the cabinet.
I changed the servo motor and also switch the servo amplifiers X to Y, but the same problem occurs.

I suspect the problem is the brake not releasing.

How to check if the brake is releasing? Any other suggestions are welcome.