Siemens Logo! Manual page 186

LOGO! functions
4.4.15 Threshold trigger
Short description
The output is set and reset with two configurable threshold
triggers.
Symbol in
LOGO!
Fre
Timing diagram
Q
G_T
Fre
178
Wiring
Input Fre
Parameter
Output Q
f = 9 f = 10
a a
f = Input frequency
a
Description
The function counts the 0 to 1
transitions at input Fre. 1 to 0
transitions are not counted.
Use
S
inputs I5/I6 for high-speed
counting (only LOGO!
12/24 RC/RCo and LOGO!
24/24o): max. 2 kHz.
S
any other input or circuit
component for counting low
frequency signals (5 Hz).
On: On threshold
Range of values:
0000...9999
Off: Off threshold
Range of values:
0000...9999
G_T: Time interval or gate time
during which the input
pulses are measured.
Range of values:
00:05 s...99:99 s
Q is set and reset at the
thresholds.
f = 8 f = 4
a a
On = 9
Off = 5
LOGO! Manual
A5E00380835-01