Citect V6.00 - ABB PM856 using COMLI


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We are having problems with communication between Citect and an ABB PM856 PLC. We are using Citect V6.0 and the COMLI driver and trying to communicate with the PLC via com port 3, which we have set to operate as via COMLI protocol. Has anyone managed to get comms working with the same setup?

P.S. The COMLI network consists of multiple I/O devices, and the Citect PC communicates via com1 & then a series of RS232/RS422 converters.
Sorry, I haven't done a COMLI link through COM3 on the AC800M but we have used Modbus successfully on this port.

However, we did once manage to break the COM3 port. I'm not sure how exactly but we manged to shove more volts through it than it was supposed to receive. The rest of the controller still continues to function to this day so it is a minor but annoying fault.

I suspect the COM3 port on the main controller is a little delicate. I would suggest you should always use an opto-isolator on COM3 or better still use a dedicated 2 port serial I/O module (CI853 I think from memory) as these seem to be more robust.


Have you solve your problem as dated November 2008 to establish communication between Citect 6.00 and ABB PM856 using Comli Protocol thru Communication Interface CI853?