SLC 5/05 to ControlLogix Messaging - Help!

We added a ControlLogix PLC to an existing network of SLC 5/05s. Primarily, to use the OLDI Module in the ControlLogix rack to send some information to some corporate databases.

Of the existing SLC 5/05s, I can setup a MSG instruction, using PLC5 as the Target, and doing a Multihop to target the IP Address and Slot of the ControlLogix - this works on ALL but one SLC 5/05.

I have been trying to discern a difference between this one SLC 5/05 and the others (that do work with the same type of message).

I am getting "Connection not completed before user-specified timeout".

Troublesome SLC is "1747-L552B/C 5/05 CPU - 32K Mem. OS501 Series C FRN 3-9"

The only difference I can see between the configuration is the other SLCs have more memory - they are "1747-L553B/C 5/05 CPU - 64K Mem. OS501 Series C FRN 3-9".

Any thoughts / ideas? Rockwell support just said to go offline, delete and recreate the MSG and go online - which we've done.

Alright, so the controllers are are setup now and not giving the error as outlined in my original post, but there are still major network issues going on.

I've worked with Rockwell, but to no avail. We have replaced some of the older Networking switches onsite as hopes to alleviate issues, but that didn't solve the problem. I've changed the following bits in the controller to 0.

S:2/15 is the "Comms Servicing Sel" bit.
S:33/7 is the "Msg Servicing Sel" bit.

The SLC-5/05s are Series B, so they max out at 10Mbps@HalfDuplex. They have been upgraded to Series-C firmware.

SLC to SLC messaging works fine, but SLC to ContolLogix works for a bit and then errors out.

Has anybody had to deal with MSG issues with older controllers and newer ControlLogix before? Any ideas would be great. Hours of working with Rockwell and having their techs look at things hasn't gotten us anywhere...

If it were a protocol problem it wouldn't work at all.

It might be a capacity problem, so we're going to have to sort out how many messages you're running on any given controller. The diagnostic web pages and a careful read of the program will help.

Have you trapped any of the MSG error codes ?

Are the MSG instructions being executed in the SLC, or in the ControlLogix ? It sounds like they're being executed in the SLC-5/05 controllers.

The larger memory controllers also have more Connection capacity... in older firmware it was something like 16, 24, and 32 connections for the L551, L552, and L553. I would have to check the release notes.

You mentioned in another thread that you'd set the older SLC-5/05 controllers for Auto-Negotiate, and had also set the switch ports for Auto-Negotiate.

RSLogix 500 does let you check the Auto-Negotiate box, because it doesn't know if it's going onto Series A, B, or C hardware. On Series A or B hardware, the setting is immaterial, as you have seen: the Ethernet port on those controllers supports only 10 Mb/s Half-Duplex, so that's all you ever see there.

My recommendation is different from the one you've received: I recommend configuring the switch ports for 10 Mb/s Half-Duplex, and disabling Auto-Negotiation.

The reasons are a long story, but I think you can prove by watching the Channel Diagnostic counters that you're getting collisions, if not FCS or checksum errors.

Set the switch port that's connected to that older SLC-5/05 for 10 Mb/s Half-Duplex and see if the error counter rates decrease.

Are all the SLCs the same firmware version?

I have had issues with PLC5 processors, where the older firmware would not communicate using MSG instructions with Micrologix, ControlLogix and CompactLogix, so firmware upgrades were required.