Alarm 8. Troubleshooting for FANUC CNC Servo Amplifier

Servo Amplifier Alarm 8., 9., A.
CNC Alarm SV0449 or SV0603
Applies to Alpha i Servo
Alarm 8., 9., or A. on the Alpha i servo amplifier is an intelligent power module alarm.

The steps for troubleshooting this amplifier alarm depends on which CNC alarm you are experiencing.

If you have an SV0449 alarm, the troubleshooting is essentially the same as if you had an SV0600 alarm. Please view the video for Alarm 8, 9 or A (no dot) for how to troubleshoot this problem.

If you have alarm SV 603, the amplifier's IPM is reporting that its temperature is too high.

Unless you know exactly which amplifiers drive which axes, the best thing to do is access the electronics cabinet with power on (safely, please) and look at the status displays of the units while the alarm is occurring. You're looking for the unit that is displaying either an 8., 9., or A. .

The servo amplifiers are in the electrical cabinet and opening the cabinet with power applied potentially exposes you to danger.

In order to accurately troubleshoot the exact cause of this alarm, you will need to have power applied to the equipment. Don't attempt to perform anything discussed in this presentation if you are not both fully qualified to do so and have the equipment owner's permission to do so.

Once you are done troubleshooting and before performing any maintenance, follow all plant safety and lockout procedures. These procedures should include releasing all energies related to the maintenance procedure performed.

OK, why are we looking for three different indications on the drives? Alarm 8., 9., and A. are all the same problem, the difference is which amplifier axis the alarm exists on.

8. is for the first axis which is labelled L on the amplifier

9. is for the second axis which is labelled M on the amplifier

A. is for the third axis, labelled N

So if your amplifier only controls two axes, like the one shown here, it should definitely never pop up an A. .

Now that you know which amplifier is alarming out, let's figure out what the trouble is. Ordinarily this alarm would indicate a short circuit but with the SV 603 alarm instead of a 449, the power module in the amp is saying it's hot but that the current flowing through it isn't high.

First thing to start with is the easiest. Pull out the grey board on the front of the amplifier by an inch or so and reseat it. You can hope for a bad connection.

On most machines the amplifiers turn on when you turn on the main breaker and then you press the ON button to turn on the CNC and bring the servo system online. If you turn on the breaker, leave the CNC turned off, and the servo amplifier has this alarm right away - the mystery is solved, bad amplifier. This issue might be intermittent or you may find that turning power on and off for a while eventually gets the amplifier to cooperate, it will continue to get worse over time until the day it completely quits.

If the alarm only comes up once the CNC is turned on, keep looking for the problem.

There's a fan on the back side of the amplifier that's supposed to keep this trouble from happening. If that fan isn't working you should be getting an alarm over it but you should still check the fan and the heatsink.

See if the fan is turning and check the heatsink to see if it's caked in goop which would stop it from cooling. Refer to the video for alarm F for how to check the fan and pull it out - if it's caked in stuff the heatsink probably is too.

Is this problem only happening when you're running a certain part? Or while doing a particular operation?

Maybe the axis is working way harder than it's supposed to which will heat up the amp. You can watch the load on the servos by pressing the Position function key and the Monitor soft key. Loads consistently over 100% lead to over heating.

When you opened up the electronics cabinet, did you feel a blast of heat hit you?

That's a pretty good sign something isn't right.

How about the temperature of the area where the machine is, in general.

Did you put the machine right next to a foundry? If the overall temperature is crazy hot, it might have an effect on the machine.

If you can't find anything hot or overheating, replace the servo amplifier.

Видео Alarm 8. Troubleshooting for FANUC CNC Servo Amplifier канала FANUC America Corporation