Powerflex 700 Comm Failure

[Ken Roach]

Okay, so you are probably back to the original problem that caused you to replace the drive and three comm modules.

The 20-COMM-D really sits between two networks: it talks to the DeviceNet scanner via DeviceNet, and talks to the drive via DPI.

If the drive can't talk to the 20-Comm-D over DPI, it gives a DPI comms fault and an "8x" error code.

If the drive can talk to the 20-COMM-D but the 20-COMM-D can't talk over DeviceNet to the scanner, the drive faults on a Network communication fault and gives an "7x" error code.

So it's very important to tell the difference. Read the code off the HIM module.

What you're at it, go to the 1788-CN2DN's node table and figure out what the error code is from the 1788-CN2DN's perspective.

 

[scadadavid]

It was giving an Error 81 indicating a problem with Port 1. Then it completely died, it went to an Initializing Screen and would never complete its initialization.

 

[JesperMP]

Just a long shot.

I once used PF700 with 20-COMM-R (RIO).
I had the same problem (I think, this is from memory), Port 5 DPI loss.
It it a ribbon-cable between the 20-COMM-D module and the PF700 ?
Take a close look at this ribbon-cable. The press-fit contacts are not the most reliable. It is also possible that it has been assembled wrongly in the manufacture, so that the wires dont have proper contact to the pins in the connectors at both ends. This is something that can surface after some time.
Maybe just exchange the ribbon cable and see if it fixes the problem.

 

[scadadavid]

Yes I checked the ribbon cables, each COMM-D comes with a new ribbon cable, I changed several of those out but the problem would persist. I would clear the fault but after 10-15 minutes it would fault back out. Then after 3-4 times of clearing that fault it went to the initializing screen and would not ever come back.

 

[alan_505]

If it is the HIM going into initialisation all the time it could also be the drives comms board called a tee board, this board has the HIM, the DPI port and the 20-COMM plugged into it, I have had failures of this board.

The problem might be getting one, it does have a part number depending on the frame size, on the frame one drives it is on the door and has the DPI port mounted on it on the larger frames I think it is on the drive and the DPI port is mounted remotely.

According to the latest parts list this boards part number is SK-H1-TCOMM for frames 2 to 10

Alan

 

[Ken Roach]

A bad tee board is consistent with his DPI problems on the fieldbus connector (5), then on the HMI connector (1). It could also be a bad main control board.

I usually saw these kinds of failures in environments where there was a lot of corrosion; salt air, sulfur dust, and carbon black are all notorious for getting drawn into drive cabinets and damaging the control boards.