Siemens SIMATIC S7 System Manual page 387

Example: Begin and Calculate interval timers
LAD
Ex1_Interval_time_net1
S7-200 SMART
System Manual, V2.3, 07/2017, A5E03822230-AF
Capture the time that Q0.0
turned ON.
Calculate the time Q0.0 has
been ON.
Program instructions
STL
Network 1
LD Q0.0
EU
BITIM VD0
Network 2
LD Q0.0
CITIM VD0, VD4
7.17 Timer
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