OPC to Symax 400 PLC


Thread Starter

A. B. Senn

Need to find an OPC Server that will talk to a SQD Symax 400 PLC. I need to talk over Ethernet.

Robert Willis

The SY/MAX Model 400 Processor only has two RS422 Serial ports which communicate using the SY/MAX Serial protocol. To convert this to Modbus TCP/IP Protocol you will need a module from www.niobrara.com you can use either the EPE5, MEB or QUCM. The EPE5 and MEB will mount directly in a SY/MAX Register slot or stand alone with a NR&D single slot rack. The QUCM module will mount in a TSX Quantum PLC rack or standalone as required. All modules will convert the SY/MAX Serial Protocol to either Modbus TCP/IP or SY/ENET. You can use any Modbus TCP/IP OPC Server to communicate to the SY/MAX Model 400. The manual for each module will explain the translation that occurs between the Modbus TCP/IP protocol and the SY/MAX Protocol and can be downloaded from the website.

Robert Willis
My preferred method:
Connect EGX-200 to NR&D EPE5.
Set the top com port to Modbus Gate.
Connect bottom port of SYMAX to NR&D and set to SYMAX.
Use Kepware modbus to connect to modbus gate port 1 one EPE5

This system is very stable and not prone to lock up as the direct EGX-200 connection is due to buffer overflow.