EUTECH INSTRUMENTS ALPHA PH 1000 PHORP CONTROLLERTRANSMITTER, Инструкция по эксплуатации, Страница: 38 / 40

Instruction Manual alpha-pH 1000
38
The output relay of the pulse length controller is clock-timed. The switching period T remains constant. Depending on the
divergence from the limit value, the switch-on time t
ON
is increased or decreased in accordance with the proportional range
Xp.
The following applies:
t
ON
+ t
OFF
= T (Const.)
greater divergence
Î
greater tON
Xp exceeded
Î
t
ON
= T (relay remains picked up)
t
ON
t
OFF
Pulse Length T
Relay
ON
OFF
Time [s]
Controller signal of Pulse Frequency Controllers
The output relay of the pulse frequency controller is clock-timed. The pulse duration t
ON
remains constant at 250mS.
Depending on the divergence from the limit value, the frequency (1/T) is increased or decreased in accordance with the
proportional range Xp.
The following applies:
t
ON
= Const. (250 msec.)
greater divergence
Î
greater f (greater frequency)
Xp exceeded Î max. frequency