Grundfos Medium UPM Series Data Booklet page 16

6
System analyser
From the preset reference duty point, the pump will
immediately start to analyse the heating pattern.
The system resistance (K
this data, a more optimal curve for operation is
selected.
3
Note: K = m /h to create a system pressure loss of
sys
1 bar.
0.2
0.18
0.16
Area B
0.14
0.12
0.1
0.08
0.06
Area A
0.04
0.02
0
30 30.5 31
Time [days]
Fig. 16 K -values logged for the system analyser
sys
If the actual duty point deviates from the reference
duty point over time, the pump will automatically adjust
its performance accordingly. If a tendency of operation
in area A is shown, the performance of the pumps is
too high. The pump will then select a lower
proportional curve. In other words, if the requirement
of the heating system exceeds the reference duty
point, the pump will choose a higher proportional
pressure curve. Should the requirement be lower, a
lower curve will be chosen.
Curve selector
H
Fig. 17 Duty point on selected proportional pressure curve
Note: The arrows symbolise the change of the
proportional pressure curve.
16
) is logged and based on
sys
Reference duty
point
31.5 32 32.5 33 33.5 34
Reference curves
A
B
Q
New reference setting
When changing the proportional pressure curve setting
to adapt to the requirements of the heating system,
AUTO automatically sets a new reference duty
ADAPT
point. From the new setting, the process starts over
again: AUTO will continuously adapt to changes
ADAPT
in the heating pattern.
H
Fig. 18 New lower proportional pressure curve
Medium UPM
Q