Siemens SIMATIC S5 Manual page 126

IP 265
Timer operations
Starting an OFF delay timer "SF":
The timer is started each time the signal at the Start
input goes from "1" to "0", and runs until the Start
signal is "1", the set time has expired or the timer is
reset.
Output Q goes to "1" when the timer is running or the
Start signal is "1" and the Reset signal is "0".
Example: Output 0.5 is set to zero 50 ms after
input 0.0.
Note
Time values become imprecise as they approach the time base. For this reason, you
should always choose the smallest possible time base.
Possible options for timer operations:
• Start and Reset inputs can be inverted.
The timer functions' output can be inverted when it leads immediately to the output bar.
•
• Each of the five timer functions can be converted into one of the other remaining four.
EWA 4NEB 812 6130-02a
Table 9-8. Timer Operations (continued)
Programming the IP 265 with COM 265
CSF (example)
0!-!T
< S
I 0.0
KT 5.0 TV
R Q
Timing diagram
Signal states
1
0
1
0
50
Q 0.5
I 0.0
Q 0.5
Time in ms
50
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