Siemens SIMATIC S7-1200 Manual page 154

Easy to communicate between devices
7.9 GPRS
In TeleService via GPRS, an engineering station on which STEP 7 is installed communicates
via the GSM network and the Internet with a SIMATIC S7-1200 station with a CP 1242-7.
The connection runs via a telecontrol server that serves as an intermediary and is connected
to the Internet.
The CP 1242-7 can be used for the following applications:
Telecontrol applications
● Sending messages by SMS
● Communication with a control center
● Inter-station communication between S7-1200 stations via a GSM network
TeleService via GPRS
A TeleService connection can be established between an engineering station with STEP 7
and a remote S7-1200 station with a CP 1242-7 via the GSM network and the Internet. The
connection runs from the engineering station via a telecontrol server or a TeleService
gateway that acts as an intermediary forwarding frames and establishing the authorization.
These PCs use the functions of the "TELECONTROL SERVER BASIC" application.
You can use the TeleService connection for the following purposes:
● Downloading configuration or program data from the STEP 7 project to the station
● Querying diagnostics data on the station
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Via the CP 1242-7, the CPU of a remote S7-1200 station can receive SMS messages
from the GSM network or send messages by SMS to a configured mobile phone or an
S7-1200.
Remote S7-1200 stations communicate via the GSM network and the Internet with a
telecontrol server in the master station. For data transfer using GPRS, the
"TELECONTROL SERVER BASIC" application is installed on the telecontrol server in the
master station. The telecontrol server communicates with a higher-level central control
system using the integrated OPC server function.
Inter-station communication between remote stations with a CP 1242-7 can be handled in
two different ways:
– Indirect communication via a master station
In this configuration, a permanent secure connection between S7-1200 stations that
communicate with each other and the telecontrol server is established in the master
station. Communication between the stations is via the telecontrol server. The
CP 1242-7 operates in "Telecontrol" mode.
– Direct communication between the stations
For direct communication between stations without the detour via the master station,
SIM cards with a fixed IP address are used that allow the stations to address each
other directly. The possible communications services and security functions (for
example VPN) depend on what is offered by the network provider. The CP 1242-7
operates in "GPRS direct" mode.
Easy Book
Manual, 11/2011, A5E02486774-04