Endress+Hauser Liquiline CM442R, Руководство по эксплуатации

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Operation Liquiline CM442R/CM444R/CM448R
74
Hauser
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
.
Typical application: dosing pump
Function="Controller"
Function Options Info
Actuator type Options
• None
• Unipolar-
• U
Factory setting
None
Here you specify what part of the controller should
power the relay. "U" is the part of the
manipulated variable which the controller uses to
increase the process value (e.g. for heating purposes).
On the other hand, select "Unipolar-" if you want to
connect an actuator to the relay that causes the
controlled variable to drop (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 mutually affect 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.
Maximum frequency
Operating mode="PFM"
1 to 180 min
-1
Factory setting
60 min
-1
Maximum number of pulses per minute
The controller calculates the pulse duration based on
this setting.