MODBUS and ControlLogix

  • Thread starter Jaime Marcelo Cedeño Pozo
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Thread Starter

Jaime Marcelo Cedeño Pozo

I need to communicate to a ControlLogix CPU with a MODBUS Plus Network. What do I need? Only the CPU with serial port, an RS 232/RS 485 adapter and the RSLogix5000 software? Do I need some kind of additional hardware or software libraries?

Thanks for your help...
For more details please check prosoft website

They provide solution to connect controllogix system to modbus network :
- MV156-MCM/MCMR modbus mater/slave (support RS-232/422/485)
- MV156-MNET for modbus TCO/IP

No special software tools required to configure the module, the module can be configured using ladder logic program through RSLogix 5000 software

Hope this help

Mark Massa,PE


Jason L. Block

Hi Jaime,

If it is truly Modbus Plus you need to convert to, we provide gateway solutions that convert Modbus Plus to one of the resident networks on the ControlLogix (EtherNet/IP, ControlNet or DeviceNet).

The product is called the Anybus X-gateway and can be viewed on the web at the following URL

If you have any questions, please don't hesitate to call me at +1 312 829 0663 or e-mail me at [email protected] or [email protected].

Best Regards,
Jason L. Block

Michael E. Crossman

Modbus PLUS is very different and separate from Modbus. It is a proprietary protocol. The other poster was correct, ProSoft makes a very nice and easy to use module, the MVI56-MBP.

There is no way to use the serial port on the processor or the other mentioned ProSoft module, which is for Modbus Serial or TCP.

Good luck,

Michael E. Crossman
PLCs Plus International, Inc.
Just to make sure we're all clear on one point, you can't program a ControlLogix PLC over Modbus Plus. The various bridge modules only translate the data read/write commands, while RSLogix 5000 and RSLinx offer no access to Modbus Plus. Since the CLx serial port isn't available for programming if it's used for Modbus, I recommend using the Ethernet module and a Modbus Plus to Ethernet/IP converter.