Controllogix 5555 MSG to a Slc 5/05 via ethernet


Thread Starter


i have lot of troubles, trying to send data from controllogix 5555 to slc 505 via ethernet. the MSG instruction doesn't seem to be fully explained in the AB reference manual. so anyone has made this instruction work?

Barrese, Robert J


You will have to check the firmware revision of the 5/05. Make sure one or both of the following is true: SLC is either a Series C or later OR Firmware 5 or later. See AB Knowledge Base 43408<pre>
Message write to LMF
Path is 1,5,2, where
1 = Common backplane
5 = slot # of ethernet card
2 = port on ethernet card = IP address of LMF PLC_G</pre>
I use a rolling time stamp as the first word of the write message from the CLX. On the SLC side do a change detect to verify valid communications.

Rob Barrese

Bob Peterson

I have never had any trouble with this kind of configuration. There are plenty of knowledge base articles about this kind of thing on the AB web site. Or you could just call tech support.

One thing that is not well explained anywhere in the AB manuals is the routing codes. That might be your issue.

Since you are being extremely vague about what is not working, it is hard to be more specific.
I haven't had any issues with that so it at least can work. It seems like you should be able to MSG from one ControlLogix to a second which has PLC/SLC mapping set up, but I've never been able to do it; you have to use produce/consume. But going from a CLX to a PLC/SLC has never seemed to be a problem.

Gerald Beaudoin

Always worked well here too. In the CTLX MSG instruction, configure for a SLC Write. On the Comm tab, for the path, I browse to the desired network, which then goes into the PATH box as the first element of the path. Then ",2" (no quotes), and then the IP address of the SLC...So my path looks like "Plant_Network, 2," I forget just what the 2 was for, but it works here!