Grundfos MAGNA 2000 Series, Installation And Operating Instructions Manual

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7.3 Automatic night-time duty
To be set on the control panel or with the R100, see
section
8. Setting the pump .
Once automatic night-time duty has been activated,
the pump automatically changes between normal
duty and night-time duty (duty at low performance).
Changeover between normal duty and night-time
duty is dependent on the flow-pipe temperature.
The pump automatically changes over to night-time
duty when the built-in sensor registers a flow-pipe
temperature drop of more than 10-15 °C within
approx. 2 hours. The temperature drop must be at
least 0.1 °C/min.
Changeover to normal duty takes place without a
time lag when the temperature has increased by
approx. 10 °C.
7.4 Constant-curve duty
To be set with the R100, see section 8. Setting the
pump.
The pump can be set to operate according to a
constant curve, like an uncontrolled pump, see
fig. 11.
MAGNA 32-120, 40-120, 50-120, 65-120
Select one of 91 curves between the max. and min.
curves.
MAGNA 50-60, 65-60
Select one of 41 curves between the max. and min.
curves.
Fig. 11 Operating curves
7.5 Max. or min. curve duty
To be set on the control panel, with the R100 or via
GENI module, see section
8. Setting the pump .
The pump can be set to operate according to the
max. or min. curve, like an uncontrolled pump, see
fig. 12.
This operating mode is available, irrespective of the
control mode.
Fig. 12 Max. and min. curves
The max. curve mode can be selected if an
uncontrolled pump is required.
The min. curve mode can be used in periods in
which a minimum flow is required. This operating
mode is for instance suitable for manual night-time
duty if automatic night-time duty is not desired.
7.6 Temperature influence
To be set with the R100, see section 8. Setting the
pump .
When this function is activated in proportional- or
constant-pressure control mode, the setpoint for
head will be reduced according to the liquid
temperature.
It is possible to set temperature influence to function
at liquid temperatures below 80 °C or below 50 °C.
These temperature limits are called T
max.
. The
setpoint is reduced in relation to the head set
(= 100 %) according to the characteristics below.
Fig. 13 Temperature influence
In the above example, T
max.
= 80 °C has been
selected. The actual liquid temperature T
actual
causes the setpoint for head to be reduced from
100 % to H
actual
.
The temperature influence function requires:
• Proportional- or constant-pressure control mode.
• The pump must be installed in the flow pipe.
• System with flow-pipe temperature control.
Note
Automatic night-time duty cannot be
used in air-conditioning systems.
TM
02
02
45
09
04
H
Q
Max.
Min.
T
M
00
55
47
45
9
6
TM
01 06
26 179
7
Q
H
Max.
Min.
30%
100%
80 50 20
H
H
Q
t [°C]
T
actual
H
actual