[dbrus38]

I am a machine shop teacher at a high school and have been working on getting a 1985 Mazak Vertical Machine Center with a Fanuc 6MB up and running. Everything was going smoothly until I ran into issues with an X axis 401 Servo error. In both the handle and zero return mode, the x axis moves about 1/4" and then sets off this alarm. This issue seemed to pop up out of nowhere. In regards to this type of error can anyone suggest how to begin troubleshooting or solving this problem? Is a 401 typically mechanical or electronic? Thanks.

[servtech]

Motor or encoder cable for break.
A tight axis may also cause this error.

With power off make sure axis is free to turn by hand (if no motor brake).

may also be the motor shorted or servo drive transistor damage.

[yours_prabhat]

The Problem related with 401 ( Stands for X axis) , Check the transistors , Fuses of the Drive , If Drive is healthy , remove the Motor from machine carefully , To put a support on X axis if its a slant bed machine keep some wooden block there , Try to run motor outside , Check the DC brushes of Motor , Important = when The alarm Comes = After starting the control ? or Once you try to Jog The axis . If The alarm Comes at startup there are very minimum chances for jamming of Axis . It may be a fault of Drive .
regards