PowerFlex 525-Fault 73.EN Net Loss. Anyway to ignore any short term Comm. Losses ?

Good Morning ,

I just recently did a project with several PowerFlex 525 drives. I just recently started getting a F 73 Fault ( EN Net Loss ) . I used all shieded ethernet cable , and I have it ran outside of the panel wireway , so it is not influenced by the 480 vac. All 16 Frequency Drives fault out with F73 , expect for one. I have no idea , why just this one sits happy.

Other than why this happens , I was also wondering if there is a parameter that I can adjust , that will ignore any short term loss of communication .
Do any of you know if there is a parameter that would "ride" thru any short term losses ?

Thanks so much for your advice.

Ok . I did some research in the manual and I see Parameter C 143 ( EN Flt Actn ) , can check keep the last values till it starts communicating again. It looks selecting this to " Hold Last " is what I want , instead of Fault.

It looks like this is the only one I need to change. Is this what you guys think ? It looks like I can change this on the "Fly" , I guess ?

Is it common to see a momentary loss of Ethernet communication in manufacturing ? What do you guys usally keep C143 set at ?

Thanks always for your help.

How is your network set up and what switches/devices are you using?

2 ) AutomationDirect Stride 16 Port 10/100

I always set C143 and C144 to "1".

No, I don't normally see that F073 fault. Only when the controller goes out of run mode or gets power cycled.

Rupej , if I set them to 1 , they will stop , correct ? I would like for them to keep running .

Would there be a bit , that I can monitor you think , that I can put on a timer , possibly ?

In my Controller Tags ( Drive Inputs ) I see ........
Comm Freq Cnt and Comm Logic Cnt

What are these ? Could I use them to monitor communication ?

Just be careful with your settings on this one. If you do have a genuine communications failure or a PLC failure, and your VSD is configured to ignore it, you'll have no way of stopping the motor. That's not good.

As to your question: you can do all the comms checking you want at the PLC end, but the issue at play is how the drive responds when it can't communicate with the PLC. The PLC might be able to say "hey, I've lost comms to the drive" and turn off its run command, but if the drive isn't communicating, nothing you do in the PLC will do a thing. The only factor at play once that occurs is your drive parameters.

I use hundreds and hundreds of PF525's, and I've never once had one display that error except when there actually was a communication fault (e.g. downloading to the PLC, unplugging ethernet cable, changing switch configuration). My advice would be, what you're seeing is abnormal and you should find and rectify the cause rather than trying to find ways to ignore it.

I agree with ASF. Unless your drive is controlling some harmless fan or lift pump or something, setting the drive to continue with its last command on comms failure is asking for trouble.

As a suggestion, you could set the drive to continue on communication fault, but, for safety, make sure the enable is activated through a physical input instead of over ethernet. That way, if it's more than a momentary glitch, or if there's another reason to stop, just drop the enable, and everything should stop.

A good place to start troubleshooting network problems is your PLC's web page. There is a lot of good diagnostic information there. Maybe you could post some screenshots and we could take a look.

FWIW, I recently had a similar problem with powerflex 753s, and a set of servos. Ultimately, we ended up running new conduit, and new ethernet cable, and it seems to have solved the issue.

Where do you guys get your shielded Ethernet cables ? I'm using AutomationDirect Stride 16 Port 10/100 Switches. The shielded cables I got was out of McMaster Carr. I have them running outside the panduit .

Thanks

Before you go buying new cables, have you tried any other kind of switch on here? Gotten into the switch and seen what is up? If you are losing multiple drives, I would look at the common denominator there.

Here is something else to check if you have not: see what the ports are set at, and the devices are set at. Sometimes automatic negotiation fails and leaves you with a half duplex connection. I've seen this cause IO fail to communicate and fault out the PLC over it. I'm not sure of the parameters for a PF drive, the switch or the PLC. It sounds like you went through a lot of trouble to limit interference already.

I know this may be way out there , but I have a total of 17 new PowerFlex 525drives and like I said earlier , all of them are faulting out with fault F 73. But, what I did notice of was , all of them fault out except one , and it does not have a fault.

Could the Control Module on the PowerFlex 525 that is not faulting out , cause all the others to fault out with a loss of communication ?

Thanks , just throwing that out there. It is so random.

If (nearly) all of my 525's were faulting with a 73, i'd be starting by replacing what links them all, the switch!