Siemens LOGO!, Manual

Page: 183 / 534

LOGO! functions
4.4 Special functions list - SF
LOGO!
Manual, 04/2011, A5E03556174-01
183
If your LOGO! is a LOGO! 0BA7, you can additionally use the actual values of the following
functions:
●
Analog filter (0BA7 only) (Page 271) (actual value AQ)
● Average value (0BA7 only) (Page 276) (actual value AQ)
● 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 (Page 172) (current time Ta)
● Asynchronous pulse generator (Page 175) (current time Ta)
● Stairway light switch (Page 179) (current time Ta)
● Multiple function switch (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
7
7/
7/ 7/
7UJ
4
7
7DLVEXV\
Functional description
A 0 to 1 transition at input Trg sets output Q.
If output Q = 0, and input Trg is set hi at least for the duration of T
L
, the permanent lighting
function is enabled and output Q is set accordingly.
The off-delay T is triggered when input Trg returns to 0 before T
L
has expired.
Output Q is reset when T
a
= T.
You can output an off-warning signal prior to the expiration of the off-delay time (T - T
!
) that
resets Q for the duration of the prewarning time period T
!L
. A subsequent signal at Trg
always resets T and the output Q.
If retentivity is not set, output Q and the expired time are reset after a power failure.