Servo failure

I have a case packing machine that uses servos. Problem is that for some reason once in a while I will get a string of servo failures and then run fine again. All my gantry accels are within what we have determined to be optimal. Using 5000 and Kinetix servos. Has anybody experience this kind of trouble or know what the causes could be? Loose cables..etc. Or how to check and see just what the problem is or if it may be happening at a certain time or point? I hope I have given enough info.

Thanks

Need more information.
What sort of failures, do the motors burn out? Does it just sit there doing nothing for a while then start operating again? Do you have to replace anything? Do the servos thrash around randomly?
What sort of system, how do you tell the servos where to position?

To start answering some of you questions, I don't use this brand of servos, but the ones I do have a serial port which you can plug in a laptop and get information on the last five failures. A similar feature is common on many drives. This could be a good starting point.

What kind of power conditioning do you have on the servo's power source? We had a rash of this a couple of weeks ago at a customer site and talked with some other vendors there too and they also said they had some goofy servo things occur. Took care of it with some EMC/RFI filtering (no other occurrences); it may help with your situation too.

Define: servo failures

I am reading it as 'servo faults'.

Is it a drive fault or is it a SERCOS problem?
What is the error displayed on the drive?
What is the error displayed in RSLogix5000 for that axis?

There aren't very many problems that can happen that do not require a fault reset for the axis to run again. Look through the program to make sure that it (the program) isn't clearing the fault as soon as it happens.

Are you getting a lot of Kinetix 6000 "MotFeedbackFault E07" faults? If so, talk to your distributor. Rockwell just released a Product Service Advisory yesterday for certain feedback cables manufactured between 11/03 and 11/05. They should be able to tell you if you have any of the affected cables.

I work for a packaging machine manufacturer. Many times I go to a customers plant for “catastrophic” servo problems only to find the 24v supply overloaded. People (many are electrical engineers) add proxes and accessories ad nausium with no thought to that little power supply.

First rule: Check the damn plug! Or see if you are getting 24V dc.
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