Siemens 6GK7242-7KX30-0XE0 User Manual
Notes on operation and configuration
4.5 Connection monitoring, data buffering, acknowledgement
CP 1242-7
40
Operating Instructions, 03/2012, C79000-G8976-C247-03
Example: The basic value 20 results in the following intervals for connection establishment
attempts:
● three times 20 s
● three times 40 s
● three times 80 s
● etc. up to max. 900 s
If a substitute telecontrol server is configured, the 4th time the CP attempts to connect to the
● three times 20 s
● three times 40 s
● three times 80 s
● etc. up to max. 900 s
If a substitute telecontrol server is configured, the 4th time the CP attempts to connect to the
substitute server, in this example therefore after the following time:
● three times 20 s redial delay +
● three times the connection monitoring time configured for the CP
● three times 20 s redial delay +
● three times the connection monitoring time configured for the CP
(time until the arrival of the TCP acknowledgement from the communications partner)
NOTICE
Depending on your contract, costs may result from each connection establishment attempt.
4.5.2
Connection monitoring time
"Connection monitoring time" parameter ("Telecontrol" mode)
The connection monitoring time is the monitoring time for the arrival of the acknowledgement
from the telecontrol server after sending a frame. If the configured time is exceeded, the
frame is buffered.
The time until the arrival of the acknowledgement depends largely on the GSM network
The time until the arrival of the acknowledgement depends largely on the GSM network
being used.
The connection monitoring time is only used by the CP 1242-7 in "Telecontrol" mode on
The connection monitoring time is only used by the CP 1242-7 in "Telecontrol" mode on
connections to the telecontrol server.
Difference: With all other connection partners of the CP, the BUSY parameter of the
Difference: With all other connection partners of the CP, the BUSY parameter of the
TC_SEND instruction retains the value 1 if there is a disruption on the connection.
The connection monitoring time is configured in the STEP 7 "Keepalive timeout" parameter
The connection monitoring time is configured in the STEP 7 "Keepalive timeout" parameter
group of the CP. Range of values: 0...600 s. If 0 is entered, the default value 10 s will be
used.
4.5.3
Frame buffer and acknowledgement
Data buffering when there is a connection abort ("Telecontrol")
If the connection to the telecontrol server is interrupted or if the connection monitoring time is
exceeded, the send frames are stored with a time stamp in the frame buffer of the CP.