Z Axis error

[ChattaMan]

Control is Fanuc O-MD on a Yang SMV1000.

At power on the control gives an alarm:

434 servo alarm: Z AXIS DETECT ERROR

When looking at the Z axis servo amp in the electrical cabinet, the digital status display is giving alarm code #2.

We don't have any manuals for this side of the machine, only for the control.

Alarm 343 says refer to DIAGNOS No. 720/727

Any ideas?

[MysticMonkey]

Alarm 434 = Check Diagnostics 720 & 727
Alarm 2 = (LV) Low control power voltage

Check across each phase for 415V

EDIT ***

Sorry I forgot, your mains power might be different to 415

[fanucman]

alarm 2 is a low voltage alarm.. check the power to the servo drive, also is this they type of amplifier with a little gray door on the front that opens sideways?

if yes then check to make sure that there is 5 volts on the jumper pins..
if no then it should be the alpha series of drives which means check the power to power supply

[ben_heinman]

May be a capacitor problem. Try turning the machine on for 5 minutes so that the alarm is on. Turn the main power off and then back on again. If the machine comes ready then you most likely have a faulty capacitor in the Z axis drive.

[ChattaMan]

3 replies sound similar. Service guy couldn't get today....all snowed in!

Machine is 10yrs old. Pic of amp below.

Thanks.