problem with servo vipers

[rolveram]

I recently acquire three viper 200 servo motor drive for a matsuura mill retrofit. In first instance we had no problems with the config of all of them separately, but when we try to run them in the machine some strange happened when we turned on that one of them begin to oscillate violently, and when we check the parameters had different value than we put in.
I think that probably may be noise but I don´t know how can I know exactly what is happening. Can someboy give me some tips to check whats going on?
rolveram

[Larken]

Get each axis working and tuned separatly before trying to run all three. Disconnect the main power to the other 2 drives while tuning each one.

What is the powersupply voltage for the control side ? Is it stable ?

Have you changed the L (loop) parameter first to its best value, while PID are set low ? ( as described in the manual)

What PID settings are you running. 400, 0 and 800 are good for testing. Change the L setting 2-8 until the motor seems most stable.

There is a small bug in the display routing that sometimes prints wrong characters when you use the ? (show settings) command. So do it a few times to get a consistant result when you use ?

Larry K