Hi,

The X and Y axis are run by professional Yaskawa servo+motor kit, so when a certain amount of steps are given to the servo, it is sure it will do that amount of steps...

It sounds like you have confidence that the servos are doing as they should, an I tend to agree for the following reason, IF the servos were losing
steps then they would fault 'following error' long before they got 7mm out from the commanded position; UNLESS you have programmed a ridiculous
'following error window', and surely you have not done that??

That would tend to suggest that either the pendant or the motion control board is losing steps. My money is on the motion controller.

Have you got any suggestions to give on software/parameter setup check-up before I go chang the hardware?

I've got no idea about XHC plugin parameters, XHC is shhitte and so I've never bothered with them.

Craig

It sounds like you have confidence that the servos are doing as they should, an I tend to agree for the following reason, IF the servos were losing
steps then they would fault 'following error' long before they got 7mm out from the commanded position; UNLESS you have programmed a ridiculous
'following error window', and surely you have not done that??

good question, I need to check, because I left this parameter at the default level.
the strange thing is, why should this "missing steps" happen when moving back (Y-) and not moving forward (Y+)....


I will doublecheck settings in Mach3, in Mach3 plugins and the servos, then if I don't find the clear source of the problem I just change the controller... so I get rid of all XHC stuff on my machine...

Adrian