How do I communicate with another PLC on the same network

Hello

I am new here. I am currently in school learning PLC's (Allen Bradley RSLogix 5000 L32E) and I am getting pretty good with it. Can anyone point me in the right direction how I can communicate with other PLCs on the same network in our computer lab?

We can only simulate 16 inputs and 16 outputs and I need 10 more inputs in order to complete a conveyor program that I am personally working on.

We have no more input modules to add to my PLC's chassis therefore I was wanting to use a neighbor's PLC's I/O. I assume this is possible but if not, how can I send a message instruction to another PLC on the same network?

Thank you all for your time in helping me with this problem!

Your time is very much appreciated.

T Smith

Do a search for produced and consumed tags.
sorry short on time

What is the "neighbor PLC"; another CompactLogix L32E ?

If it's a ControlLogix with 1756-series I/O you can just add it to your I/O tree over Ethernet, whether as the sole owner of the module or a listen-only connection.

If not, Produced/Consumed Tags or MSG instructions are the two other mechanisms for transferring data between controllers. They're well documented in the User Manuals and the Knowledgebase.

Let's start by defining exactly what platform and part number the "neighbor" I/O is.

Ken Roach said:

What is the "neighbor PLC"; another CompactLogix L32E ?

If it's a ControlLogix with 1756-series I/O you can just add it to your I/O tree over Ethernet, whether as the sole owner of the module or a listen-only connection.

If not, Produced/Consumed Tags or MSG instructions are the two other mechanisms for transferring data between controllers. They're well documented in the User Manuals and the Knowledgebase.

Let's start by defining exactly what platform and part number the "neighbor" I/O is.

Click to expand...

So there are 11 PLC's in the lab and they are all identical. I will have to find the part number tomorrow morning when I go in the lab. Sorry.

Thanks for your help though!

If I understand you correctly, all the controllers in the lab are CompactLogix 1769-L32E, so all the I/O is the Bulletin 1769 Compact type. You can't control Compact I/O from another controller on the Ethernet network, nor can you do Listen-Only connections over the network. Those functions are specific to the Bulletin 1756 ControlLogix family of I/O.

Instead, you can use Produced/Consumed tags or Message instructions.

Produced/Consumed Tags are pretty well described in the ControlLogix System User Manual, and in publications like 1756-PM011, Produced and Consumed Tags Programming Guide.