MicroLogix on DH485 but I want it on RS485


Thread Starter


Dear all,

I have never used Allen-Bradley PLCs, but now I am using 2 MicroLogix PLCs on a DH 485 network.
I want to get the data on SCADA but the SCADA does not have that driver.

Please can anyone tell me is it possible to take it on RS485 so that I can directly take it on Modbus? Please tell me this thing, I will be very thankful to you all.
Hi Kamal,

My preferred option would be to run it through an OPC gateway such as RSLinx set up to communicate with the DH 485 driver. Using an OPC client on the SCADA the data from the PLCs could be brought in.

However you'll need to presumably purchase the OPC server and an OPC client that can be used by the SCADA plus include set up time.

There are off the shelf protocol converters which claim to do this directly, although I haven't used one for DH485 to Modbus. Search the net for DH485 to Modbus converter as you need to convert the protocol (RS 485 is a data communications standard not a protocol) from DH485 to Modbus in order for your SCADA to understand the data (assuming you're using a SCADA which is using a Modbus Interface.

Evandro Carlos Vizicato

If the Micrologix is a Micrologix1500 or Micrologix1200 or Micrologix1100 you don´t need any converter. You just need to change the configuration of Channel 0 to Modbus Master or Slave on the Channel configuration Screen.