User Manual

LOGO! functions
4.4 Special functions list - SF
LOGO!
Manual, 06/2014, A5E33039675
139
3. Press to move the cursor to the "B" of the shown block, and then press to select the
required block number.
4. Press
to move the cursor to the block's timebase and press to select the required
timebase.
The view in parameter assignment mode appears as follows, for example:
Timing diagram
Functional description
A 0 to 1 transition triggers the time T
a
at input Trg (T
a
is the current LOGO! time).
If the status of input Trg is 1 at least for the duration of the configured time T, LOGO! sets
the output to 1 on expiration of this time (the output follows the input with on-delay).
LOGO! resets the time when the status at input Trg returns to 0 before the time T expires.
LOGO! resets the output to 0 when the signal at input Trg is 0.
If the block is retentive, LOGO! resets output Q and the expired time to the values before a
power failure; if the block is not retentive, LOGO! resets output Q and the expired time to
defaults after a power failure.