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7. Detailed descriptions
7.1 Control modes
H = Pressure (Head)
Q = Flow
Control modes
Description
Illustration
Constant speed
Open loop
The setpoint of the booster system will be interpreted as setpoint
for the system performance.
The setpoint value is a percentage of the maximum performance
of the subpumps.
No sensor is required.
Constant pressure
Closed loop
The setpoint of the booster system will be interpreted as setpoint
for the pressure.
The controller in the booster system will change the booster speed
so that the pressure is constant, regardless of the flow.
A pressure sensor is required.
Constant flow
Constant level
Constant temperature
Constant percentage
Closed loop
Constant flow, constant level, constant temperature or constant
percentage can be obtained by replacing the main pressure sensor
with another sensor, e.g. a flow sensor is needed for flow control,
a level sensor is needed for level control and a temperature sensor
is needed for temperature control.
Constant flow is illustrated to the right.
Proportional pressure
Closed loop
The setpoint of the booster system will be interpreted as basic
setpoint for the proportional-pressure mode (the black dot in the
illustration).
A pressure sensor is required.
H
Q
H
Q
H
Q
H
Q
