Siemens S7-1200 PLC communicates through Sinaut MD720-3 cellular modem

Siemens S7-1200 PLC communicates through Sinaut MD720-3 cellular modem

Many consumers, including myself, have tapped into the ever-growing functionality of mobile internet. Many people leverage this infrastructure for their mobile phone. Others are beginning to use WiMAX connections for their PCs. Not to be out-done, PLCs are also capable of communicating through wireless data plans.

DMC just finished the proof-of-concept phase in a project using the new Siemens Simatic S7-1200 PLC and Siemens Sinaut MD720 GPRS GSM cellular modem. We were able to successfully send data from the PLC, through the cellular network, to the Siemens Sinaut Micro SC OPC server, and view the data on multiple OPC clients such as a WinCC Flexible HMI. We were also able to send data back to the PLC using the same connection. Additionally, the PLC is capable of sending SMS text messages through the modem.

This technology seems best suited for communicating with distributed PLCs in remote applications, where hard-wired networking is unavailable or not practical. Data logging, alarming, and parameterization are just a few valuable functions that can be performed remotely.

Learn more about DMC's Siemens S7 PLC programming expertise.


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# Rohit

Have you followed the steps given in the documentation below? I've tried this and didn't have any issues as such. How about addressing the tags in your OPC client and even the "name" of the OPC server in the client's configuration?

# Derek
Hello, I am currently trying to communicate with S71200 PLc communicating through RS232 port to Siemens MD720 GPRS Modem. As pictured above. When I run my OPC Server I cannot view the data coming out of the PLC. I can view the data leaving the Modem ie signal strength, bytes recieved and sent etc but nothing from the PLC. I have tried various methods to do this. Using the Siemens Sinaut SC server the GPRS modem connects and at both ends appears correct. When I run my OPC client then no data.
As a second option I have ran a Kepware server. There are no RS232 drivers for the S71200.
I am using the library program provided by Siemens on this. So far no clear answers from Siemens locally.
Can anyone help on this?
Nick Shea
# Nick Shea

Since we developed this implementation for a client of ours, we are not able to supply a manual or source code.

As of today, Siemens has not yet released the manual for the new S7-1200 Sinaut library. If you contact your local Siemens rep, they may be able to help you find an early release. In the meantime, the manual for the older S7-200 Sinaut implementation might have the information you are looking for:

If you have any specific questions, however, I may be able to help point you in the right direction.

Best Wishes,
Douglas Ferreira

My name is Douglas and I am trying this same solucion with the new library Siemens, but unsucessible.

Do you have a manual about your implemetantion?

Thanks for help,

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