Knick Stratos Evo A402, Руководство пользователя

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Pulse Length / Pulse Frequency Controller
Pulse Length Controller (PLC)
The pulse length controller is used to operate a valve as an actuator. 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 %)
ON time (Y = 20 %)
Pulse length
1
0
1
0
Pulse Frequency Controller (PFC)
The pulse frequency controller is used to operate a frequency-controlled actuator (metering pump).
It varies the frequency with which the contacts are switched on. The maximum pulse frequency
[pulses/min] can be defined. It depends on the actuator.
The contact ON time is constant. It is automatically calculated from the user-defined maximum
pulse frequency:
ON time
Pulse frequency (Y = 20%)
Pulse frequency (Y = 80%)
1
0
1
0
Output signal (relay contact) of pulse frequency controller
Output signal (relay contact) of pulse length controller
PID Controller
PID controller and behavior during HOLD
The following setting can be made for the controller: HOLD MODE = Y LAST/ Y OFF.
Y LAST: The controller output Y is maintained during HOLD
Y OFF: Y = 0 during HOLD (no control)
For a continuous (non-integrating) process, you should use the Y LAST setting.
For an integrating process (closed boiler), you should use Y OFF.