CIP Motion Control

I have 5 Powerflex 527 STO CIP Safety drives being used as CIP Motion Control axis with control logix version 31.11 on a 5069-L340ERMS2 processor. The drives are daisy chained back to a Stratix. I am getting Control Sync faults on 2 of the drives. I either have to clear faults on the axis(drive) or cycle power to get them running again. I have unsuccessfully tried to look this up online multiple times. I don't have a TechConnect contract and every technote is requiring it. Any advice would be immensely appreciated.

Thanks

Kevin

Have you tried to increase the scan rate of the controller?

sounds like you are having comm issues with the drives? Can you check to see how many port faults RSLinx comes up with?

The drives are daisy chained back to a Stratix.

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Can you describe that in more detail ? Is there a Device-Level Ring architecture, or are you just daisy-chaining a series of drives from a single port on a Stratix switch ?

Is the switch a managed model with IEEE 1588 PTP, or one of the inexpensive unmanaged switches ?

Are there any other devices on the network ? Is the CompactLogix the PTP Grandmaster clock ?

Do you get the control sync faults on the same two drives every time ? What's their position in the daisy chain ? Do the faults occur when the drives are idle, or only when they are running ?

Ken Roach said:

Can you describe that in more detail ? Is there a Device-Level Ring architecture, or are you just daisy-chaining a series of drives from a single port on a Stratix switch ?

Is the switch a managed model with IEEE 1588 PTP, or one of the inexpensive unmanaged switches ?

Are there any other devices on the network ? Is the CompactLogix the PTP Grandmaster clock ?

Do you get the control sync faults on the same two drives every time ? What's their position in the daisy chain ? Do the faults occur when the drives are idle, or only when they are running ?

Click to expand...

There are a total of 5 daisy chained to one port on the stratix. It only occurs on 2 of the 5. Honestly I am not sure when they fault. Seems to be mostly when at idle, but these drives are feeding a carton magazine and start and stop based on a photo eye at the top of the magazine. The STratix is a 1783-BMS10CGP A2. The OEM lost the password and it's not any default I've tried and I don't have enough experience with stratix to really mess with it. The OEM told me to wipe it and redo it, but then he told me Rockwell did it for him so he can't talk me through it. This machine is a prototype and the OEM was learning on the fly. I will have to check tomorrow on the Grandmaster clock. I believe it's the CompactLogix, but I'm not sure.

Thank you!

robo77 said:

Have you tried to increase the scan rate of the controller?

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The OEM didn't properly size the controller and it's at 96 percent capacity. I'm scared to make any scan time changes. I know the one time my compatriot made a change it messed up our motion controls drastically.

97% processor utilization is a bad gig. I have never been anywhere near that kind of utilization before I started running into all sorts of odd occurrences. I would say you are lucky to be operating as well as you are. It could be that the axes that are faulting are just missing processor sync messages for too long a period because the plc is swamped doing other things.

Do you have any axes that do not require quite so precise control? If you are swamping the controllers capability you might be able to split the axes into two or three motion update rate groups.

The default if for all axes in a motion group to be included in the default course update rate. However, you can set up to three different update rates.

Open your motion group properties page. Select the "Attribute" tab. there you will find the Base Update Period as well as an Alternate 1 and Alternate 2 update. You can set different update rates for each of these. Click the Axis Schedule button in the upper right of the window to set which axes operate in which update. By getting your less intense axes into longer update rates you might free up some processor resources.

Keith

You can also try sticking the drive chain directly into one of the PLC ports. This bypasses the need to have CIP sync enabled managed switch.