Need Help!- Fanuc 6m 400, 403 servo errors

[EPS]

I've poured through the forums on this topic and I'm still having trouble. The machine is a Hitachi wire edm with 4 axis. 2 (x,y) are common fanuc a06b-h001's and the other two (u,v) are much smaller a20b-0006 drives.

Background. I turn the machine on and a series of contactors drop powering up various pumps etc.. one contactor powers the servos. It comes one for a few seconds and then drops off with a 403 alarm. I used to be able to power down and back up to clear it but not any longer. If I hit reset and run around the machine real fast (no helper) I can see the ready light blink on for both drives (x,y) then right back off. The u,v drives have no lights. I've read about the hcal lights and others but none of these are on.

So now I can hit "reset" and the contactor tries to power up but drops right back off with the 403 alarm. Once in a while for good measure it will give me a 400 alarm or both 400 and 403 at the same time. If I disconnect a servo cable it causes other faults.

[EDM_Fixer]

403 is your V axis. Check the plug going into the UV box. Open the cover turn the gear on the V with it turned off. Does it feel rough? Try the U do they fell the same? The ways will rust if the static pressure isent maintained W/dry air.

[EPS]

I'll check that today. I went through and checked voltages on the pins for the x and y drives and my 24 volts reads 27v. Is that enough to create an overcurrent condition?

Is there a way to disable a drive or motor without causing faulting so I can narrow down the problem?

[EDM_Fixer]

It sure will.
27 vdc on a 24 vdc line is over 10%. It will mess you up.
Sounds like it will be EZ fix... Once you find it... LOL ... sorry ...You'll find the right supply transformer.
Later Jim