Siemens SIMATIC S7 System Manual page 383

TONR retentive On-delay timer example
LAD
Timing Diagram
S7-200 SMART
System Manual, V2.3, 07/2017, A5E03822230-AF
10 ms TONR timer T1 times out at
PT = 1 s (100 x 10 ms).
T1 bit is controlled by timer T1.
Q0.0 is ON after the timer accumulates
a total of 1 second.
TONR timers must be reset by a Reset
instruction with a T address.
Reset timer T1 (current value and bit)
when I0.1 is on.
Program instructions
STL
Network 1
LD I0.0
TONR T1, +100
Network 2
LD T1
= Q0.0
Network 3
LD I0.1
R T1, 1
7.17 Timer
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