[Crashmaster]

Sorry if this is posted in the wrong area, I run a Wasino LJ-103m CNC lathe with a Fanuc 10t Control. I was happily running parts today when I received a
SV 04 alarm, excess voltage in servo on the C axis. I believe I can power down and back up and the alarm will clear, however, I don't like clearing alarms without knowing what the hell caused them and if there is something maintenance wise I should be doing to prevent this. Any comments/advise would be great.

[Al_The_Man]

I moved this to the Fanuc forum.
Excess voltage is often caused by regeneration caused by a fast deceleration of an axis or defect in braking resistor, this is not usually the case with a C axis as it often does not turn fast, but if you have a large load this can cause it or, check you incomming supply voltage or servo supply voltage, Fanuc's are often sensative to too high a main supply.
Most are rated at 200vac ±10%.
Al.

[Crashmaster]

It's funny you bring up defect in the braking resistor. I recently blew one of the two fuses to the braking resistor, they must be related. I have a tech coming out today for another machine, I will have him look at it.

[Al_The_Man]

If you have replaced the fuses, check the resistors for open.
Al.

[Jimmy Lay]

Hi all member I'm using CD-SERVO type 1702 in bending machine, and having problem, alarm " Under Voltage " display is shown, any suggestion how or where to fix this problem ? , please send to [email protected]
Thanks

[keebler303]

Increase the voltage.