I'm working on a 3 axis milling machine fitted with three Gemini servo drives, two of the drives have part number: GV-U12E-NK the third is GV-U6E-NK. The machine has been working perfectly since it was commissioned in June.
Yesterday the Z axis stopped working. The z-axis drive light is red although it is enabled. I have checked the wiring and the enable input is definitely connected to ground.
Five minutes later the X axis also stopped working again the enable signal looks fine.
The Y axis continues to work perfectly although all three drives are connected to the same 240V supply.
If I use Motion Planner to communicate with the drive bits 13 and 14 on the TAS report are set, these are 'Drive shutdown' and 'Drive Faulted' respectively.
If I get a TASX report bit 2 is set, this is 'Low voltage fault' this is the same on both faulted drives.
The Y axis drive is on the same voltage supply and continues to operate correctly and does not show this fault. I measure between 245 and 250 VAC on the drive power terminals.
If I issue a TDVBUS command I get the value 339 which I think is correct.
As a precaution I have replaced all ac wiring to the drives but cannot get the fault to clear.
Page 161 of the 'Gemini series programmers reference' says that to clear this fault I should send a DRIVE1 command. I have done this multiple times on both faulted drives together with resetting the drives and cycling the power but I cannot get the fault to clear. Occasionally I can hear the internal relay click but it returns to the disabled position within half a second.
Given that the fault only affects the 12A drives this is starting to look like a firmware issue.
Issuing a TREV command to the functioning 6A drive gives
A TREV to the 12A drive gives
So it appears that the 6A drive has older firmware installed.
Any assistance you can offer would be appreciated as I need to get the machine operating ASAP.