Siemens SIMATIC S5-100U, System Manual

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The Integral Real-Time Clock S5-100U
12.2 Setting Parameters in DB1, for CPU 103 Version 8MA03 and Higher
Set the clock parameters in DB1 to be able to use the clock functions. Follow the same rules you
used in setting parameters for other functions. Refer to section 9.1.
Procedures for Setting Parameters in DB1
1. Perform an overall reset.
2. Output default DB1 to the programmer.
3. Use the cursor to jump into the clock parameter block.
4. Change the parameters.
5. Transfer the changed DB1 to the programmable controller.
6. Switch the programmable controller from STOP to RUN.
Every time there is a change from STOP to RUN, the programmable controller accepts the new
clock data.
Note
The system data contents are deleted during an overall reset. The clock continues to run
internally with the current values.
The clock time is updated one second after the next cycle starts.
12.2.1 Defaults
The following values are preset in the parameter block when you output the default DB1.
Figure 12-1. DB1 with Default Parameters for Integral Real-Time Clock
36: KS ='PGN 01 ; #CLP: CF 0 ';
48: KS ='CLK DB5 DWO STW ';
60: KS ='MW102 STP Y SAV Y ';
72: KS ='OHE N SET 4 01.04.92 ';
84: KS ='12:00:00 TIS 4 ';
96: KS ='01.04. 13:00:00 OHS ';
108: KS ='000000:00:00 # ; SDP: WD';
After the CLP block ID for the integral real-time clock, the CLK parameter defines the location of the
clock data (in DB5 beginning with DW0, for example). The STW parameter specifies the location of
the status word (in flag word MW102, for example). You must specify both parameters if you want
to read the clock.
Section 12.2.2 describes the procedures you must follow to read the clock.
Section 12.2.3 lists all of the parameters that you can use for the integral clock.
12-2
EWA 4NEB 812 6120-02b