CNC Lathe 401 # Alarm Solution

What should I do if the 401 # alarm appears on the CNC lathe?

A CNC lathe uses FANUC 0 TD system. This CNC lathe has a 401 # alarm for a period of time.

First, check whether the servo board is intact and no problems are found;

then check the power supply and find that the control power supply has no voltage, so it is judged that there is a problem on the periphery of the machine tool.

Call up the ladder diagram to check the cause of the alarm. It is found that the VT signal makes the 401 # alarm. The switch is suspected to be damaged first.

After checking, there is no problem. After measuring 24V DC, there is no voltage.

After the exclusion, the machine tool resumes normal operation.