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Entry type: Application example Entry ID: 54361177, Entry date: 06/15/2016

Sending and Receiving SMS Messages via a SCALANCE M Router

  • Entry
  • Associated product(s)
A SIMATIC S7-1200/1500 station is to automatically send important information about the plant status, alarm messages or warnings to mobile service personnel using the SCALANCE M874/M876 router.

In areas where no wired transmission medium is available and where setting up a separate wireless network involves excessively high costs, data transmission via SMS using the GSM cellular network is a simple, reliable and cost-effective alternative.
Using a simple SMS-based escalation system, the SIMATIC S7-1200/1500 sends a warning/message to the service personnel via the SCALANCE M874/M876 router. To connect the SIMATIC S7 CPU to the GSM network, the S7 station is connected to the Ethernet interface of the SCALANCE M874/M876 router via TCP/IP.

The following functions are implemented in this application example:

  • Sending a message to a service employee
  • When a configurable time – during which no acknowledgment SMS message has been received – has elapsed, the message is forwarded to other configurable service employees in an escalations chain.

The solution presented here offers the following advantages:

  • The blocks of the “LSmsSR” library encapsulate the basic SMS functions in conjunction with the SCALANCE M874/M876 routers.

  • The blocks of the “Escalation SMS” application example provide you with application code for message management that can be used immediately and is easily extended.

Library for STEP 7 V13
  Library description (1,0 MB)
 Registrierung notwendig  Library (1,2 MB)

Application example for STEP 7 V13
  Documentation (1,2 MB) 
 Registrierung notwendig  Project (9,0 MB)

The following archives contain these SMS functions for older SCALANCE routers.
 Registrierung notwendig Sending SMS Messages with an S7 CPU via the UMTS Router SCALANCE M873/ M875 (2,9 MB)
 Registrierung notwendig SMS Messaging with S7 CPU via EGPRS Router MD741-1 (285,0 KB)

Further Information
Wireless Signaling and Switching per SMS with S7-1200 Controller
Wireless Signaling and Switching via SMS with serial CPs/CMs and the MD720-3 GPRS/GSM Modem

Last Changes
First version

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