Drives

[draman]

We use two Ultra 3000 controllers on a single machine. Each controller runs a servo motor that turns a set of drive rollers to pull coiled wire through a set of straightener rolls. The machine is eight years old and was running without problems until recently.

Our PLC control has begun to give errors ... "a motor is in open loop" followed by "servo move taking too long". When this happens the wire fails to feed. We believe the servo motor fails to spin as we do not see evidence of the drive rolls spinning on the wire. Once the errors occur the drive does not respond to input from the PLC.

On the Ultra 3000 controller the LED indicator does not show any error codes. Ultraware also does not show any faults to clear. Our only option is to power down our entire machine. Sometimes we have to power down the machine two or three times before the controller / servo motor will repsond. We feel this is probably due to powering it back up too soon (capacitance) but mention it here in case it is important.

At times in the past we have had a few E20 and E23 errors. The E23 errors can be avoided by adjusting the straightening rolls to put less pressure on the wire. We understand that the E20 errors are likely caused by EMI and have taken steps to minimize that.

We are hoping someone can get us started on a likely path for troubleshooting this problem.

Thanks