Ethernet/IP CJ2 to Controllogix

[gamerayers 0]

I am currently working on project which requires me to communicate from a CJ2M-CPU33 to a SLC5/04. Unfortunately, this is not so easy with the fact that the SLC5/04 is only DH+ or Serial. What I was able to do is was find a Controllogix CPU, Ethernet card and DH+ card laying around and I have a msg block which allows me to communicate between the SLC and the Controllogix through DH+. I had a test bench setup where I was able to communicate between the CJ2M and the Controllogix using the same Bytes as the Message Block so the Controllogix basically became a passthrough and this was done all over Ethernet/IP. The thing was, when I went to implement the communicate on the plant network, the CJ2M and the Controllogix were on different switches and in different subnets. The CJ2 was 10.73.49.32 and the Controllogix was 10.70.3.39. I was finally able to get communication from the CJ2 to the Controllogix to the SLC, but unfortunately, communicate from the SLC ends at the Controllogix and the CJ2 never receives anything back. To get the communication working to the Controllogix, I had to enable Unicast on the Controllogix, but when I did similar enabling of Unicast on the Controllogix to send back to the CJ2, it didn't seem to fix anything. Any ideas on how to get the communication working the other direction?

[pat.stave 1]

Is there a gateway present on the network? Is both EIP-cards set up to use this gateway? Is the gateway set up to route 10.70.xxx.xxx-10.73.xxx.xxx? Do you use the correct subnet mask for your class B network (255.255.0.0)? Do you use explicit (cyclic) or implicit messaging (on demand)? Which PLC is the EIP communications master?

[gamerayers 0]

I have the master configured as the CJ2M. I have changed the subnet to 255.255.0.0, and it doesn't seem to fix it. There is a gateway which is configured to do that, but I am unsure of the exact configuration as our network is extremely large. Both PLC are set to use a gateway, but they are different gateways. The gateway for 1 is 10.73.49.1, and the other is 10.70.3.1. I believe that it is cyclic as there is no commands to send or receive data is was all just configured as sort of a remote I/O. I am getting ready to have my network group setup some data recording on the Cysco switches to see if they can watch if my packets are making it from one switch to the other or not.

[BobLfoot 301]

For my two cents I would set this up as follows: message read command in CLGX for CJ2_DATAOUT read to CLGX into CLGX_TAGSET1 message read command in CJ2 for CLGX_TAGSET2 read to CJ2 into CJ2_DATAIN message read comamnd in SLC for CLGX_TAGSET1 read into SLC_DataIN message read command in CLGX for SLC_DataOUT read into CLGX_TAGSET2 And then work on whichever message instruction was failing. Hope that might help.

[gamerayers 0]

I am currently using message read commands for the CLX to the SLC. Both directions work. Without message reads, I am using I/O addressing for the Ethernet/IP communication, and the CJ2 can send the data to the CLGX but receives no data back. Therefore, the area that isn't working CJ2 for CLGX_TAGSET2 read to CJ2 into CJ2_DATAIN. I tried to seperate the commands in the CLGX so that it wasn't strickly passing, it was storing the CJ2 data, and it didn't change anything. I have had my network guys look into it and they said they will get back to me soon about possible routing issues in the switches.

[gamerayers 0]

So I was able to do a test with an Omron to Omon CJ2 in the same areas using the same Implicit commands. When I first set it up, I was using Multi-cast connections and neither PLC could see eachother. When I switched the CJ2s to Point-to-point, everything worked wonderfully. From what I can find out, the network is blocking multi-cast/boardcast connections from one switch to another, but a unicast or point-to-point seems to work find. I believe the issue I'm having is that the CJ2 cannot be set to read messages from the Controllogix using Point-to-point or unicast, the only option is multicast. Is there anyway around this? I would try to use explicit messaging, but the issue comes down to timing. The one PLC is a conveyor controller and the other is for a piece of equipment which needs to know when the conveyor is stopped. Timing needs to be within 500ms or so. The larger delay the worse the performance of the machine would be. Plus, the explicit message structure is a bit hard to understand from the Omron side.