Siemens SIMATIC ET 200AL, System Manual

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Communication with the redundant system S7-1500R/H
14.2 Response to Snycup
Communication
414
Function Manual, 05/2021, A5E03735815-AJ
14.2 Response to Snycup
Response of communication connections via the system IP address in the system state SYNCUP
• HMI, PG- and S7-connections are temporarily closed. For a short time during the SYNCUP it
is not possible to establish connections to the S7-1500R/H redundant system.
• All existing connections of Open User Communication are interrupted:
– Connections set up by the CPUs of the redundant system as an active connection
partner are set up again after the SYNCUP.
– The S7-1500R/H redundant system sets up connection endpoints again for the passive
connection establishment after the SYNCUP.
• The processing of running instances of the instructions TSEND and TRCV is stopped. The
block parameter STATUS returns 80C4
H
(temporary communication error).
14.3 Response to primary-backup switchover
Response of communication connections via the system IP address during a primary-backup
switchover
• Running instances of the instructions TSEND and TRCV are stopped and return the status
80C4
H
(temporary communication error).
• Connections successfully established by the S7-1500R/H redundant system are established
again by the new primary CPU.
• The new primary CPU sets up connection endpoints again for the passive connection
establishment.
Note
Increased duration of connection interruption
If the remote system does not transmit actively after the primary-backup switchover, the
connection monitoring (e.g. TCP-Keep-Alive or application) may have to be performed by the
remote system until the connection can be re-established.