Siemens LOGO! Series Manual page 350

Determining the cycle time
Explanation
The inverted flag block changes its output signal at each program execution. Thus, one logic
level (high or low) width is exactly equivalent to the length of one cycle. Hence, a period lasts
2 cycles.
The threshold trigger indicates the ratio of periods per 2 seconds, which results in the ratio of
cycles per second.
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Manual, 04/2011, A5E03556174-01
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