SCL505 to PLC5 ethernet communication


Thread Starter


Can I connect a PLC5 to a SLC 505 using ethernet? I need to exchange information between the two PLCs. What instructions do I use for communication between the two?


Bob Peterson

yes. they both have to be ethernet versions of the CPU, or have an external ethernet adaptor of some sort. the MSG instruction would be used.
ummm unless i missed a memo, its pretty straighforward. Just connect the processors to each other (through a switch/hub or with a crossover cable) and use a MSG instruction. I dont have access t the PLC5 software right now, but in RSLogix500, there is a PLC5 option under the target device setting on the MSG blocks. The only way it gets any simpler is if you get someone else to do it for you.


Jeremy Pollard

You can use a cross over cable and use the MSG instructions - check out the help file for both regarding syntax.

Cheers from: Jeremy Pollard, CET The Crazy Canuckian!
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This is pretty easy if you are using fixed IP addresses. Copy and paste
the following as a rung in RSLogix500 software:

MSG WRITE PLC5 LOCAL N7:0 1 N7:0 N7:0 1 5 0

...and explore the resulting Message instruction. Obviously, your IP address, data file locations, and data word length will be different.

Hope this helps!

Larry Lawver
Rexel / Central Florida
Yes you can. Using the MSG (message) Instruction. For futher information read the PLC5 Instruction set Help under the help tab of your PLC5 English software.