Detailed Descriptions; Control Modes - Grundfos CIM 300 BACnet MS/TP Instructions Manual

7. Detailed descriptions

7.1 Control modes

Control modes Description
Open loop
The setpoint of the booster system is interpreted as the setpoint for the system
performance.
Constant speed
The setpoint value is a percentage of the maximum performance of the pumps.
No sensor is required.
Closed loop
The setpoint of the booster system is interpreted as the setpoint for the
Constant pressure pressure.
Constant diff. pressure The controller in the booster system adapts the pump speed so that the
pressure is constant, regardless of the flow.
A pressure sensor is required.
Constant flow
Closed loop
Constant level
You can obtain these control modes by replacing the main pressure sensor by
Constant temperature
another relevant sensor. For example, a flow sensor for flow control, a level
Constant diff. temperature
sensor for level control, or a temperature sensor for temperature control.
Constant percentage
Constant flow is illustrated on the right.
Closed-loop sensor control
Closed loop
The setpoint of the booster system is interpreted as the setpoint for
proportional-pressure mode (the black dot in the illustration).
Proportional pressure
A pressure sensor is required. In this control mode, the booster system
automatically adjusts the setpoint according to changes in flow, in order to save
energy.
AUTOADAPT
For this control mode, the optimum setpoint is automatically estimated and
used. This also means that any setpoint value is ignored.
AUTOADAPT
A pressure sensor is required.
This control mode is not supported by all products.
FLOWADAPT with flow limitation
For this control mode, the optimum setpoint is automatically estimated and
used, but the flow is limited by the maximum flow-limit value set by the user.
FLOWADAPT
Set the value with AO, 5.
This control mode is not supported by all products.
H = Pressure (Head)
Q = Flow
For tank filling, see section Tank-filling applications.
Related information
7.7 Tank-filling applications
Illustration
H
Q
H
Q
H
Q
H
Q
H
Q
H
Q
31