20-comm-s

Anyone ever set up a 20-COMM-S before? Cant get mine to communicate with the PLC 5.

Dear Grider,
I know nothing of 20-Comm-S . . . .

But what I've just seen suggests it is an Ethernet port module for PowerFlex PLC's.

If your PLC-5 is like my PLC-5 it runs a very old thing called 'DataHighway +'.
I think you might need an Ethernet module specifically for a PLC-5 system.
MadPoet.

The 20-COMM-S is a serial interface for PowerFlex 70/700 family motor drives. It implements the A-B DF1 protocol over an RS-485 physical layer.

These were not a common product. The usual way they were used was as a low-cost way to connect to multiple drives with a configuration computer (with DriveTools) by connecting to just one with a 1203-SSS and then using the daisy-chained 20-COMM-S modules.

You can, in theory, send messages to these modules from the serial port of a PLC-5 Enhanced/ControlNet/Ethernet controller.

But it wouldn't be the usual way; RIO or ControlNet would be the typical methods for connecting a PLC-5 to a PowerFlex drive.

So, what exactly have you done at the physical/electrical level, and at the programming level, to connect this module to the PLC-5 ?

But what I've just seen suggests it is an Ethernet port module for PowerFlex PLC's.

Click to expand...

Serialously?

Not Ethernet! I am well versed in setting up communications with Powerflex over Ethernet. The issue I have here is that a older 1336 plus using dh+ to a PLC 5 was replaced with a powerflex 753 and handed over to me to program and get comms setup between it and the PLC 5. I was going to use a 20-COMM-R, but I need the version 1.010 for it to be compatible. My local dealer says they are obsolete now and she cannot get them. I found the 20-COMM-S on the shelf, but have never set one up in this application or don't even know if its possible. Is there something else I can use for this application??

Okay, so you had a 1336 Plus drive with Remote I/O (not DH+, even though the wiring is identical). That makes sense.

RIO was the principal remote I/O protocol for the PLC-5, though you can use ControlNet on the models equipped with that, or DeviceNet using a scanner card.

PLC-5 controllers of course don't run I/O over Ethernet or over their serial port.

You *could* send MSG instructions repeatedly to the drive over the PLC-5's Channel 0 serial port using DF1 messaging, and that would work with the 20-COMM-S.

But that's slow, and difficult, and not nearly as reliable as a true I/O network.

What sort of physical connection do you have set up, and what kind of logic and protocol settings have you tried ?

I am just starting on this, so I have not tried anything. Just getting a plan together. The location is in a small building a mile from my plant. I do have a fiber going out to the building for the PLC communication back to the plant. I can take a spare and setup a stratix switch. I didn't really want to spend a lot of time and money on this because there are only three VFD's and a few valves on this PLC rack. There is no hardwire I/O between the PLC and the drives. Whoever set this up, they were only using the blue hose for status/commands.

Found a 20-COMM-R with the newer version. Connected to the PLC, just need to figure out the parameter settings for the data links.