MODBUS and ControlLogix

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...

I think prosoft has a module you could use.

For more details please check prosoft website

http://www.prosoft-technology.com

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

I'll save you a couple of thousand dollars in hardware and labor!
Use the logix 5000 internal Modbus driver.
The Logix controllers starting with Rev 13 have a modbus loadable.

See the app note below.
http://literature.rockwellautomation.com/idc/groups/literature/documents/ap/cig-ap129_-en-p.pdf

This will use up the onboard serial port on the controller and you can add a Converter for Modbus Rs-485 or Modbus TCP (a couple of $100 from Moxa)

Good Luck,
Mark Massa,PE

These are all good responses, but the OP needs to connect to MB+, which is different from regular old MB or MB/TCP.

Unless Prosoft makes a unit that goes directly to MB+, you would need a MB-to-MB+ converter as the last piece of the equation. Several companies make them: our company makes one called the MBP-100, information on which can be found here:

http://iccdesigns.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=ICC&Product_Code=10490

Darrin

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

http://www.anybus.com/products/abx.asp

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

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.
http://www.bkppi.com

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.

Mike