Siemens SIMATIC NET TeleControl S7-1200 CP 1243-1 Operating Instructions Manual page 41

Note
If the partner cannot be reached, connection establishment via the mobile wireless
network can take several minutes. This may depend on the particular network and current
network load.
Depending on your contract, costs may result from each connection establishment
attempt.
● Send monitoring time
Time for the arrival of the acknowledgment from the partner (Telecontrol server) after
sending unsolicited frames. The time is started after sending an unsolicited frame. If no
acknowledgement has been received from the partner when the send monitoring time
elapses, the frame is repeated up to three times. After three unsuccessful attempts, the
connection is terminated and re-established.
Default setting: 60 s. Permitted range: 1...65535 s.
● Watchdog monitoring time
With the watchdog cycle, the CP checks the connection to the telecontrol server. The
watchdog cycle is the interval without data exchange between the CP and telecontrol
server after which the CP sends a watchdog frame to the telecontrol server. The
watchdog cycle is only configured with TCSB (parameter "Keepalive monitoring time").
The value configured in TCSB is transferred by the telecontrol server to the CP the first
time the connection is established.
Each time the CP transfers data to TCSB and receives the acknowledgment from the
telecontrol server, the CP starts the watchdog cycle. When the watchdog cycle has
expired the CP sends a watchdog frame to the telecontrol server.
After sending a watchdog frame, the CP starts the watchdog monitoring time within which
the CP expects a reply from the telecontrol server. If the CP does not receive a reply from
the Telecontrol server within the monitoring time, it terminates and re-establishes the
connection.
Default setting: 30 s. Permitted range: 0...65535 s. If you enter 0 (zero), the function is
disabled.
● Key exchange interval
Here, you enter the interval in hours after which the key is exchanged again between the
CP and the telecontrol server. The key is a security function of the telecontrol protocol
used by the CP and TCSB V3.
Default setting: 8 s. Permitted range: 0...65535 s. If you enter 0 (zero), the function is
disabled.
CP 1243-1
Operating Instructions, 12/2016, C79000-G8976-C365-02
4.5 Ethernet interface (X1) > Advanced options
Configuration
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