Proportional Pressure; S-System Configuration; Normal And Inverse Control - Grundfos Control MPC Installation And Operating Instructions Manual

8.7.9 Proportional pressure (4.1.7)

Fig. 47 Proportional pressure
Description
The function can only be enabled in pressure-controlled systems
and automatically adapts the setpoint to the actual flow rate to
compensate for flow-dependent dynamic losses. As many
systems are designed with extra flow capacity, the estimated
maximum flow rate (Qpmax) can be entered manually. In systems
with CR pumps, the pump curves can be used to calculate the
maximum flow rate at the selected setpoint. A filter factor can be
set to prevent fluctuation.
The adaptation can be linear or square. See fig. 47.
H
C B
A
Fig. 48 Proportional pressure
Pos. Description
Pressure at 0 flow. Starting point of proportional-
A
pressure control (influence at 0 flow = x % of setpoint)
B Qpmax
C Setpoint
The function has these purposes:
• to compensate for pressure losses
• to reduce the energy consumption
• to increase the comfort for the user.
Setting range
• Selection of control mode.
• Influence at 0 flow
• Estimated flow rate
• Filter factor.
Setting via control panel
• Settings > Primary controller > Proportional pressure.
1. Select: Enabled.
2. Select:
• Adaptation
• Linear / Square.
3. Set: Influence at 0 flow.
4. Set: Filter factor.
5. Select: Use pump curve / Enter value.
6. Set "Qpmax" if you select "Enter value".
32
Factory setting
The function is disabled.

8.7.10 S-system configuration (4.1.8)

Fig. 49 S-system configuration
Description
The function makes it possible to invert the control of mains-
operated pumps (MPC-S). That is to set whether pumps are to be
started or stopped depending on the actual value.
A start/stop band must be set in order to use this function.
See fig. 50.
Normal
A pump is stopped when the value becomes higher than H
start/stop band. And a pump is started when the value becomes
lower than H . See fig. 50.
set
Inverse
A pump is started when the value becomes higher than H
start/stop band. And a pump is stopped when the value becomes
lower than H . See fig. 50.
set
Normal
Q
H [m]
Pump stops
Start/stop band
H
set
Pump starts
Time [sec]
Fig. 50 Normal and inverse control
Setting range
• Selection of configuration (normal or inverse).
• Start/stop band.
Setting via control panel
• Settings > Primary controller > S-system configuration.
1. Select: Normal / Inverse.
2. Set: Start/stop band.
Factory setting
Normal.
set
+
set
Inverse
H [m]
Pump starts
Start/stop band
H
set
Pump stops
Time [sec]
+