ControlLogix: Connect a Local WonderWare to Remote PLC

This ControlLogix PLC is located remotely via fiber. At the PLC location, the fiber comes in, goes through a "BlackBox" converter, then out to the PLC via CAT-5. I know I can connect directly to the PLC via the USB port, but I'd like to run the Wonderware application right there, too. Without an open network port/plug, do I need to interpose a temporary switch between the BlackBox and the PLC or is there a simpler solution?

Adding a switch sounds like a simple solution. I don't think you are going to find a simpler one.

Sounds like you have a media converter (fiber to Ethernet) which then connects to your PLC using a patch lead.

A simple unmanaged switch will do the trick. If you want to stay in AB world then use a Stratix 2000 5-port 1783-US5T. A couple of patch leads and off you go.

Thanks for the feedback. Our IT people lent me a 5-port unmanaged NetGear switch, so we'll give it a spin later today. Got lots of communication problems to this particular PLC, which is redundant, but the redundancy has never worked. Gonna pull the redundancy, for sure, to see if that improves the situation any, then go from there. Having the Wonderware local will be an interesting test, too...

There's a Redundancy Module configuration and diagnostic utility that gives you information and statistics and logs about the redundancy features of ControlLogix. Each bundle of ControlLogix Redundancy release has an appropriate version of the SRM Utility that is bundled with it.

I would encourage you to troubleshoot the redundancy system carefully instead of simply disabling it or turning it off to troubleshoot network issues.

One of the most common misunderstandings on Redundancy is that the Ethernet modules need to be able to connect to one another over the TCP/IP network in order to function properly. After all, if they're meant to connect to an HMI or engineering workstations, they need to be on the same network.

I've seen quite a few systems where the two Ethernet modules were connected to totally separate networks in the name of separation for reliability, and of course they didn't work properly because the Ethernet modules couldn't confirm that their partners were present over both Ethernet and over the RM module link.

SoftwareJanitor said:

Thanks for the feedback. Our IT people lent me a 5-port unmanaged NetGear switch, so we'll give it a spin later today. Got lots of communication problems to this particular PLC, which is redundant, but the redundancy has never worked. Gonna pull the redundancy, for sure, to see if that improves the situation any, then go from there. Having the Wonderware local will be an interesting test, too...

Click to expand...

I would suggest that if your Ethernet/IP network consists of consumer switches like NetGear then this could be giving you problems with your network.

I've seen unmanaged D-Link consumer grade switches used in complex Ethernet/IP networks that would lock up nearly once a shift and require power cycling to start switching traffic again.

Ken Roach:

Yeah, was just trying to simplify initially, to see what effect dropping out the redundancy had. Turned out the comms errors were much fewer and farther between, but they didn't go away completely. There was at least one BlackBox fiber converter that was either undersized for the distance of the run, or it was just starting to slowly fail? Replacement with a longer-distance box (MM1300) seems to have cleared everything up, but now the redundancy needs to be turned back on to see if that is OK. Probably will be, but if not, will have to find that utility. Never heard of that and don't know if we have it here or not. As for the Ethernet modules, they are on the same network here.

brendan.buchan:

The NetGear box was just temporary. We have professional-grade switches here.

And, not a big deal, but I wasn't able to get the Wonderware communicating locally (thru the temporary NetGear switch) because I needed RSLinx (and possibly even SuiteLink ??) running on this Windows 7 laptop? This is the older version Wonderware (non-Archestra)

brendan.buchan said:

I would suggest that if your Ethernet/IP network consists of consumer switches like NetGear then this could be giving you problems with your network.

I've seen unmanaged D-Link consumer grade switches used in complex Ethernet/IP networks that would lock up nearly once a shift and require power cycling to start switching traffic again.

Click to expand...

I've also seen that happen with industrial grade switches. A failed (or failing) switch is a failed (or failing) switch.

FS Gateway in DAServer is also needed for topic configuration in Intouch.

mike_dr:

Yeah, found out about that after-the-fact. So you need *both* RSLinx AND FS Gateway running *together*? And this is because of what - the version of InTouch, the Microsoft Operating system in use, or both?