I have read all the older SRVO-018 posts but I am still stuck. Maybe it's my testing methodology, this is my first Fanuc robot.
I have an R-2000iA with a R-J3ib control cab that is tending an injection molding machine. Last friday while the arm was mid pick it faulted out as an srvo-018. The three steps given to fix this fault are to check the RM1 connection. Check the CRR64 connection. Replace the amp. I have now tried all three, with no luck.
In checking for shorts I have used both an ohm meter, and a megger. Here is the breakdown of what I have done so far.
Disconnect the brake connectors from each servo motor. Inspected the connector and plug for anything loose or cracked or broken. I then pulled the RM1 connector from its housing to check for loose or broken wires on the back of the connector.
With all the brake connectors off the servos I did a 120v megger test on the brake pins at the RM1 connector ( pins 11, 12, 13, 23, 33, 44, 45, 46) Checking between the pins and the body of the robot. The lowest resistance I found was around 900 mega ohms. Next I pulled the CRR64 connection inside the controller and checked continuity from there to the end of the RM1 cable. All the wires passed.
I plugged the RM1 cable back into the robot. I ran an extra ground wire from the robot to the grounding plate in the control cabinet. Still with the servos disconnected I meggered at 120v from the CRR64 connection. All the wiring passed. My lowest resistance reading was still around 900 mega ohms. I ran this test as a 30 second and a 90 second megger test. Next I metered between each wire of the CRR64 to see if they were leaking between each other and not to ground. No continuity between the wires.
I reconnected all of the brake connectors to the servo motors. I did a regular resistance reading from the CRR64 again. No shorts, and resistance readings line up with what I would expect a coil to read.
I cleaned the RM1 and CRR64 connectors. Checked the small fuses on the amp. Checked the amp for 24v at its test pins. Pulled the amp out of the controller and gently cleaned it while looking for any bad components. Reinstalled the amp and rechecked just about every connector again.
I metered the brake pins on each servo motor. The motors that are all the same size had all the same readings, and the three larger motors had reading that seemed normal for a coil.
Last ditch I ordered a new amp and installed it. Still the same error.
I don't know what other connections I can check, or if I am somehow checking them wrong. I guess it's possible that one of the servo brakes failed internally and that is why I am getting the error, but I don't know how to check for that.
Any ideas?
