Notes on configuration and operation
5.8 Reading out time by CPU
CP 1242-7 V2
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Operating Instructions, 05/2014, C79000-G8976-C311-00
Interaction between the main and substitute server
In a normal situation, the stations are connected to the main telecontrol server. If the main
server cannot be reached, the connection of the remote S7-1200 with the CP 1242-7 GPRS
V2 fails over from the main to the substitute server.
Switchover between the main and substitute server by the CP 1242-7 GPRS V2
When establishing the GPRS connection to the telecontrol server, the CP automatically
switches over to the substitute server after the 4th dialing attempt if the main server cannot
be reached.
If the substitute server cannot be reached either, the 4th time the CP once again tries to
connect to the main server.
The intervals of the redial attempts are controlled by the "Redial delay" parameter.
You will find an example in the section Redial delay (STEP 7) (Page 40).
5.8
Reading out time by CPU
Requirement
Before the CPU can read out the correct time-of-day from the CP, the time-of-day of the CP
needs to be set. The options for time-of-day synchronization of the CP via the Internet can
be found in the section Other properties of the CP (Page 11).
Reading out time by the CPU with RDREC
You can read out the CP time of day with the RDREC "read data record" instruction. To do
this, create a block of the type RDREC.
The parameters of the RDREC need to have the following settings:
ID
As the logical address, enter the hardware identifier of the CP 1242-7 GPRS V2.
MLEN
Enter a length of 12 bytes.
INDEX
For the index, enter the data record with the number 160.
RECORD
Specify a structure of the data type DTL as the target area.
