Constant-Curve Duty; Max. Or Min. Curve Duty; Temperature Influence - Grundfos MAGNA 2000 Series Installation And Operating Instructions Manual

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. 6.
When the pump has been set to constant-curve
mode with the R100, the setting can be changed on
the control panel or with the R100.
MAGNA 25-100, 32-100, 40-100(D), 50-100
Select one of 9 curves (81 curves with the R100)
between the max. and min. curves, see fig. 5.
MAGNA 25-80, 32-80, 40-80
Select one of 7 curves (61 curves with the R100)
between the max. and min. curves, see fig. 5.
MAGNA 25-60, 32-60, 40-60
Select one of 5 curves (41 curves with the R100)
between the max. and min. curves, see fig. 5.
MAGNA 25-40, 32-40
Select one of 3 curves (21 curves with the R100)
between the max. and min. curves, see fig. 5.
Min.
Fig. 5 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. 6.
This operating mode is available, irrespective of the
control mode.
Min.
Fig. 6 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.
15
Max.
Max.

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
setpoint is reduced in relation to the head set
(= 100 %) according to the characteristics below.
H
actual
T
actual
Fig. 7 Temperature influence
In the above example, T
max.
selected. The actual liquid temperature T
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.
Temperature influence is suitable in:
• systems with variable flows (e.g. two-pipe
heating systems), in which the activation of the
temperature influence function will ensure a
further reduction of the pump performance in
periods with small heating demands and
consequently a reduced flow-pipe temperature.
• systems with almost constant flows (e.g. one-
pipe heating systems and underfloor heating
systems), in which variable heating demands
cannot be registered as changes in the head as
is the case with two-pipe heating systems. In
such systems, the pump performance can only
be adjusted by activating the temperature
influence function.
Selection of T
max.
In systems with a dimensioned flow-pipe
temperature of:
• up to and including 55 °C, select T
• above 55 °C, select T
The temperature influence function
Note
cannot be used in air-conditioning
systems.
. The
max.
= 80 °C has been
actual
= 50 °C,
max.
= 80 °C.
max.