MODBUS RTU drivers in WinCC 7.3

Dear Experts,

We have following query kindly suggest solution asap,

We have Delta DVP14-SS2 PLC and WinCC 7.3 Update 1 SCADA. And we have to communicate both with MODBUS RTU (RS485) serial communication.

But the hurdle is we can not find MODBUS RTU drivers in WinCC 7.3, instead we find MODBUS TCP/IP driver.

So kindly suggest can we install MODBUS RTU drivers in WinCC 7.3 or we have to us MODBUS TCP/IP gateway to convert MODBUS RTU.

If we have to use Gateway then suggest how we can configure it ???

Kindly revert with your valuable solutions.

Thank you in advance.

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Split from wincc scada 7.2 with different plc communication.

Hello zopeparag;

WinCC V7.3 no longer supports Modbus RTU directly (the last version to do so was 5.2). Look at the list of available channels for WinCC communication, from this manual:

WinCC V7.3: Communication

https://support.industry.siemens.com/cs/fr/en/view/102691766

Siemens recommends using their OPC channel whenever you want to connect to a PLC using a serial connection, such as Modbus RTU. 

Search for an OPC server you can connect to your Delta PLC, there are many links such as this one on the web:

Delta Serial OPC Server - OPC and DCOM Hands-on Training

Another option is to purchase and install a Modbus RTU channel designed for WinCC by Allmendinger:

MODBUS Protocols Channel for WinCC - Allmendinger

A last possibility, if your Delta PLC supports Modbus/TCP, would be to onnect directly to the WinCC Modbus/TCP channel; if it only supports Modbud RTU, you could look into using a converter from Modbus RTU to Modbus/TCP for your project. Here is one model from Moxa, there are many more on the web:

Modbus RTU/ASCII to Modbus TCP gateways - Moxa Online

Hope this helps,

Daniel Chartier