User's Manual

LOGO! functions
4.4 Special functions list - SF
LOGO!
Manual, 04/2011, A5E03556174-01
173
● Max/Min (0BA7 only) (Page 273) (actual value AQ)
●
On-delay (Page 160) (current time Ta)
●
Off-delay (Page 164) (current time Ta)
●
On-/off-delay (Page 166) (current time Ta)
●
Retentive on-delay (Page 168) (current time Ta)
●
Wiping relay(pulse output) (Page 170) (current time Ta)
● Edge triggered wiping relay (current time Ta)
●
Asynchronous pulse generator (Page 175) (current time Ta)
●
Stairway light switch (Page 179) (current time Ta)
●
Multiple function switch (Page 182) (current time Ta)
●
Stopwatch (Page 198) (actual value AQ)
●
Threshold trigger (Page 210) (actual value Fre)
Select the required function by the block number. The timebase is configurable. For
information on valid ranges and parameter defaults, refer to the
On-delay (Page 160) topic.
Timing diagram A
7+7+
4
7UJ
7/ 
1 
7KHEROGVHFWLRQRIWKHWLPLQJ
GLDJUDPDOVRDSSHDUVLQWKH
V\PERORIWKHHGJHWULJJHUHG
ZLSLQJUHOD\
7DLVUXQQLQJ
Timing diagram B
4
1 
7UJ
7/ 7+7/ 7+
7LPLQJGLDJUDPIRUWKHVDPSOH
FRQILJXUDWLRQ
Functional description
A 0 to 1 transition at input Trg triggers the time T
L
(Time Low). After the time T
L
has expired,
output Q is set for the duration of T
H
(Time High).
If there is a further 0 to 1 transition (retriggering pulse) at input Trg before the preset time (T
L
+ T
H
) has expired, T
a
is reset and the pulse/pause cycle is restarted.
If retentivity is not set, output Q and the time are reset after a power failure.