Endress+Hauser Liquiline System CA80NO, Руководство по эксплуатации

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Operation Liquiline System CA80NO
90 Hauser
1. PWM (pulse width modulation):
The duty cycle is varied within a period T (T=t
1
+t
0
). The cycle duration remains
constant.
0 T
t
1
t
0
2T 3T
y = t / T
1
10 % 50 % 100 %
1 "High"
0 "Low"
t
 72 Typical application: solenoid valve
2. PFM (pulse frequency modulation):
Here, pulses of a constant length (t
1
) are output and the interval between the pulses
varies (t
0
). At a maximum frequency, t
1
= t
0
.
1 "High"
0 "Low"
T
t
t
1
t
0
2T
y = f / f = T / T
max min
100 % 50 %
20 %
3T
 73 Typical application: dosing pump
Function = Controller
Function Options Info
Actuator type Selection
• None
• Unipolar(-)
• Un)
Factory setting
None
Here you specify what part of the controller
should power the relay.
Un) is the part
of the manipulated variable which the controller
uses to increase the process value (e.g. for
heating purposes). Alternatively, select
Unipolar(-) if you are connecting an actuator to
the relay that reduces the controlled variable
(e.g. for cooling purposes).
Cycle duration
Operating mode = PWM
Shortest turn-on time to
999.0 s
Factory setting
10.0 s
‣
Specify the cycle duration within which the
duty cycle should be varied (only PWM).

The settings for Cycle duration and Shortest turn-on time influence one another. The following applies:
Cycle duration ≥ Shortest turn-on time .
Shortest turn-on time
Operating mode = PWM
0.3 s to Cycle duration
Factory setting
0.3 s
Pulses that are shorter than this limit value are
not output in order to conserve the actuator.