No chance of identifying the cause as you have changed hardware and that controller may not be configured the same.
How do you know the replacement controller is configured the same, please explain?
Also what do mean robot occasionally restarts?
Sounds like internal harness issue in arm to me.......
Backups and comparison backups will help to see if any difference is in software between controllers.
I can not explain it
I suggested replacing the control because it seemed the easiest for them who have never worked with a robot and since I am no longer at their facilities.
About the robot/control setup all the controls are, if I remember correctly, C42 and all the arms are ZX-300S.
Even so, I have already suggested that for this type of hardware failure it would be best to work with a local supplier with experience in such failures.
The part that worries me the most is the momentary activation of the outputs on boot (or restart) of the robot.
About the "occasional reboot of the robot".
It does its complete work cycle (nailing spikes on a pallet) and when returning to HOME through the instructions JMOVE p1, JMOVE p2 and JMOVE p3 the control is restarted (as if you turn off the general switch during execution and turn it back on) at the p2-p3 transition.
The latter has only occurred as a result of the change of control. It does not happen in all cycles but when it does it is always in the same position.