alarm 55 servo lag

[bgmike2011]

im working on a mazak 630 multiplex and for several months now been fighting this alarm. have changed motor encoder and wiring from controller to encoder and frequently we get this alarm .daily ,weekly to much any suggestions would be great.

[Karsue]

On which head you get the alarm (HD1 or HD2)???
Have you check coupling between motor & ball screw??? If it is fine change your controller (I think RG221B or A) from head 1 or 2, to head 2 or 1 and see if alarm goes from one head to another head then your drive controller is not good.
Let me know by result, I had also few times same alarm on my few different MPX but every time the problem was different than the other one.