communications with controllogix


Thread Starter


what is the best way to recieve data from an as400 system to an allen bradley controllogix system connected to a pc via ethernet running wonderware hmi software.


Paul Karnopp

I worked on a project 10 years ago where we had to do the same thing.

We had an interposing PC between the the AS400 and a PLC5/60E. The PC was programmed in Visual Basic (VB) in order to read shop order information and to write shop floor information to/from the AS400 databases. The PC also had RSLinx to allow the VB program to read and write data to the PLC's data tables.

Bear in mind, the program in the PLC got very complex because of the data storage and handshaking with the PC. The flexible data structures of ControlLogix should make your job easier.

Automation Linse

The ControlLogix ethernet protocol is quite complex.

First suggestion - can your HMI dump a text "report" to a file and FTP or email it to the AS400?

Otherwise, you should look into adding a Modbus/TCP slave driver to the HMI. Them have WW HMI pull data from the ControlLogix and write it to the Modbus driver. Writing a Modbus/TCP client on the AS400 would not be hard for an average AS400 programmer.

best regards
- LynnL,

Mark Hensley (Kepware)


Based on what Lynn says you could use our ControlLogix OPC server and our Modbus TCP/IP OPC server in conjunction with our LinkMaster product to move data from the ControlLogix into a form that you could read from the AS400.

Additionally you could also use our UCON driver (User CONfigurable) if you already have some form of protocol on the AS400. The UCON driver lets you create an OPC server simply, only requiring that you know the protocol of your target system. The LinkMaster product lets you move data between OPC servers regradless of whether or not they are Kepware's or someone elses. In this way you would simply map the tags from the ControlLogix into either the Modbus TCP/IP driver or into the UCON driver and the AS400 would either access the Modbus TCP/IP driver or UCON would pump the data directly into the 400.

Here are the relavent links:

Please keep in mind these links may have wrapped and you may need to reconstruct them before they work.