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Entry type: Application example Entry ID: 22537809, Entry date: 09/25/2014

Micro Automation: Wireless Data Communication based on GPRS (MAS 21)

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  • Associated product(s)
Note The SIMATIC S7-200 components used in this application example are currently phased out. ...

The SIMATIC S7-200 components used in this application example are currently phased out.
This application can be realized as easily and quickly with the new SIMATIC S7-1200. The respective application example with SIMATIC S7-1200 is available here: 39863979

Furthermore, many useful applications with SIMATIC S7-1200 are available here: 35923253

Automation task
The infrastructure of a wastewater treatment plant contains the substations “Stormwater Overflow“ and “ Inspection Shaft“. Both are supposed to communicate with each other and with a control center. The Internet-based GPRS service, which charges by data volume, should be used as a data transfer medium. The control center should enable central operator control and monitoring.

Automation Solution
The automation solution uses the SINAUT Micro SC remote control system with the GPRS modem MD720-3

  • to visualize process data from the Remote Stations at the Central Station or

  • to exchange process data between the Remote Stations.

Remote Station “Stormwater Overflow“
The S7-224 controls pump “P1“, which pumps the water of the stormwater overflow structure into the water treatment plant. Pump “ P2“, which can be operated manually via the Central Station, enables pumping the water into a nearby river. All process data are transferred to the Central Station via the GPRS modem MD720-3.

Remote Station “Inspection Shaft“
The S7-224 controller measures the amount of wastewater influx and, in function of the filling level, controls the pump “P3“, which pumps the water into the treatment plant. All process data are transferred to the Central Station via the GPRS modem MD720-3. In the event of a connection disruption, a non-volatile buffer will save all of the process data together with a time stamp until the GPRS connection is active again.

Central Station
The OPC server SINAUT MICRO SC is used as a platform for data exchange with the Remote Stations. The Central Station communicates with the GPRS nodes via Internet connection. As OPC client, WinCC flexible enables visualization and control of the process data. Furthermore, the values can be written with time stamp into a CSV file.

Startup Code
For the startup we offer you software examples with test code and test parameters as download. The software examples support you during the first steps and tests with your Micro Automation Sets. They enable quick testing of the hardware and software interfaces between the products described in the Micro Automation Sets.

To operate a SIMATIC S7-200 with a MODEM MD720 along with the Telecontrol Server Basic, revised/new block libraries are available under the following link 99522310.


Download contents Downloads
Micro Application Example
Set21_DocTech_v3d3_en.pdf ( 2574 KB )
WinCC Add On Set21_WinCC_DocTech_v1d0_en.pdf ( 772 KB )
SOAP Add On Set21_SOAP_DocTech_v1d0_en.pdf ( 1217 KB )
Startup Code (SINAUT MICRO SC Configuration (*xml-file)) m2mopc.zip ( 332 bytes )
Startup Code for Remote Station "Inspection Shaft" and "Stormwater Overflow" (STEP 7-Micro/WIN Projects) MAS21_S7-200_V2D2_en.zip ( 119 KB )
Startup Code (WinCC flexible Project, *.hmi, *.fwx) MAS21_WinCCFlex_V2D0_en.zip ( 3508 KB )
Startup Code (STEP 7-Micro/WIN Library) MAS21_S7-200-Bibliothek_V1D16.zip ( 33 KB )
Startup Code (WinCC Project) MAS21_WinCC_V1D0_en.zip ( 2728 KB )
Startup Code (HTML Client for SOAP Connection, simple version "simple") HTML_Client_V1d0.zip ( 1 KB )
Startup Code (HTML Client for SOAP Connection, complex version "Set 21") HTML_Client_MAS21_V1d0.zip ( 177 KB )


Link contents


System manual GPRS/GSM Modem SINAUT MD720-3 23117745
SINAUT MICRO SC System manual 23119827
Micro Automation Set 5 21063345

New Option "SOAP" for Webvisualization with WinCC flexible.

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