CompactLogix SERCOS Error

I stopped by to look at a problem with a new machine, the machine uses a AB compactlogix processor and two 1768-M04SE SERCOS modules for communication with the servo drives. The machine would not start, indicating a fault with one of the servo motors however I noticed that the I/O light was flashing green on the processor and both 1768-M04SE modules displayed the following code:

CP Light - Solid Orange
Ring Light - Off
OK Light - Flashing green

I have not been able to find information with regard to this exact error code, has anyone encountered this error before?

Yes. The problem occured in any of four Sercos drives in a pouch filling machine. Although we can't be certain, I think the problem was ground-related. About three months ago, an employee received amild shock while holding onto a product line and picking something up off the floor. There was no obvious cause for this, but a couple days later, one set of windings in a 100Hp homogenizer motor became partially open to ground, which led to the main MCC breaker tripping. Upon inspection, we found there was a very light mist of water from a breached heat exchanger tube in the vicinity of the motor. We swapped the motor and drove a 10' ground rod through the plant floor and into the sub-soil, to which we grounded the homogenizer. We haven't had a Sercos fault since, and we would normally have had one or two a week. It could be coincidence, but I doubt it.

In any case, check grounding.

I'm not sure which servo drives you are using, but if it's anything like the kinetix 6000's then possibly the following has happened:-
At some time since the last time the machine was powered down some one has interrogated the drive settings, as there is no database for the servo you are using it looks for data in its default database (motion.db
)it does warn you but if you ignore the warning it will change your settings for that servo indicated by an * in the settings tab effected, but nothing happens and the servo will run as normal until the system is power cycled then the new setting (using default database)are used causing the errors - you need to either contact AB for the database or generate your own custom data.
I think the database - motion.db is in C:\program files\rockwell software\rslogix5000\enu\v17\bin the version no. is the version you are using.

Are the servo drives showing an error code?

Steve

There are two servo networks (Kinet2000 & 6000) each connected to one 1768-M04SE module. All drives display the following code

Fault/Status Segment : Keeps making circles in a clockwise direction

Drive LED: Off

Comm LED: Off

Bus LED: Flashing green

Hope this new information helps.