Siemens LOGO! - Page 167

159
LOGO! Manual
A5E00380835-01
Timing diagram
T
a
is busy
T
Q
Trg
T
L
T
L
T
!L
T
!
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 dura-
tion 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 be-
fore 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
!
), to reset Q for the duration of
the off-warning signal T
!L
. A further 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.
Preset of the Par parameter
Note the defaults specified in Chapter 4.3.2.
Note
T, T
!
and T
!L
must all have the same timebase.
View in programming mode (example):
B5 1+R
T =60:00s
TL =10:00s
Protection mode and retentivity
Off-delay
Permanent light on-time
LOGO! functions