Modbus Communication Between ControlLogix5570 and Mark VIe


Thread Starter


I happy to join this forum which has expert engineers in control system. This is my first thread, and have a question.

can I use modbus communication with controllogix5570, directly or should use prosoft products? I just know the product name in somewhere of this forum but didn't googled it yet :)

Thanks in advance for answering or even for passing here....

Real Time Automation has gateways that will help you connect a ControlLogix with a Modbus device. Depending on what type of Modbus device you are connecting to, a Modbus TCP/IP Client or Server (over an Ethernet connection) or Modbus RTU Master or Slave (over a serial connection), the 460ETCxx line sounds like something that would be helpful.

Set up is web based, with you defining the tags in your ControlLogix and finding the various Modbus registers you are looking to Read/Write to. They will Auto Map the two together, with you having the ability to manually map them, if need be.

Hi Angel,

Controllogix PLC should be able to communicate directly (without 3rd party devices) using Modbus TCP directly thru their standard Ethernet module (EN2T or EN2TR). But since Controllogix CPU don't have ready to use Modbus function block, you will need to implement your own Modbus Algorithm into your routine (Ladder, ST or FB). Rockwell Knowledgebase 470365 provide the sample of Modbus TCP program that you can refer to:

<b>Moderator's Note:</b> you will have to register to use Rockwell's knowledgebase.
Dear MattP and Ikhtiander,

Thanks for your reaction. I am still read something related.
I will come back again..

How do you plan to communicate? Modbus RTU, ASCII or TCP? Regardless i have worked with Prosoft equipment on AB ControlLogix 5570 and as far as i can tell it's the fastest and easiest way to do it.