Hach-Lange SI794 D tr User Manual - Manual (Page 80)

Controller functions
Pulse length / pulse frequency controller
Pulse length controller (PLC)
The pulse length controller is used to operate a valve as an actua-
tor. It switches the contact on for a time that depends on the
controller output. The period is constant. A minimum ON time of
0.5 sec is maintained even if the controller output takes
corresponding values.
ON time (Y = 80 %)
Output signal (relay contact) of pulse length controller
ON time (Y = 20 %)
Pulse length
1
0
1
0
80