Hi everyone, I discovered this forum just recently, and will really appreciate it if anyone has a similar experience with this case I am having and is willing to give some tips.
Our company owns a CTX400 Serie 2 CNC lathe machine by DMG, and its main spindle does not turn anymore!

Here is what I did:
1. I initialized the CNC (Closed the safety door, turned the drive on, clamped the chuck, initialized the feed to reference point, specified tool number)
2. I set the main spindle speed to its minimum (50 rpm)
3. I commanded the spindle to turn either CW or CCW (both does not turn)
4. The whole drive stopped, and error message appeared, saying "No phase current in S1 axis motor lines" Then, the message told me to check "the DC link voltage, motor feed lines, and fused in the power module."
I merely checked the three power wires going to the main spindle with the clamp ammeter, and it showed that each wire carried a constant and same amount of current upon activation.

Sometimes the spindle would slightly twitch after command, but that's it.

Does anyone have any idea about how to fix this? Thank you!