Brochure

Functions
MAGNA3
8
28
FLOW
ADAPT
The typical pump selection is based on required flow
and calculated pressure losses. The pump is typically
oversized by 30 to 40 % to ensure that it can overcome
the pressure losses in the system. Under these
conditions, the full benefit of AUTO
ADAPT
cannot be
obtained.
To adjust the maximum flow of this "oversized" pump,
balancing valves are built into the circuit to increase
the resistance and thus reduce the flow. The
FLOW
ADAPT
function reduces the need for a pump
throttling valve.
Note: This function cannot eliminate the need for
balancing valves in heating systems.
Fig. 26 Reduced need for a pump throttling valve
The FLOW
ADAPT
control mode combines a control
mode and a function:
• The pump is running AUTO
ADAPT
.
• The flow will never exceed a selected FLOW
LIMIT
value, which reduces the need for a pump throttling
valve connected in series with the pump.
Fig. 27 FLOW
ADAPT
control
When FLOW
ADAPT
is selected, the pump will run
AUTO
ADAPT
and ensure that the flow never exceeds
the entered FLOW
LIMIT
value.
The factory setting of the FLOW
ADAPT
is the flow
where the AUTO
ADAPT
factory setting meets the max.
curve. See fig. 27 and section Selection of control
mode, page 24.
Proportional pressure
This control mode is used in systems with relatively
large pressure losses in the distribution pipes. The
head of the pump will increase proportionally to the
flow in the system to compensate for the large
pressure losses in the distribution pipes. The setpoint
can be set with an accuracy of 0.1 meter.
The head against a closed valve is half the setpoint
H
set
.
Fig. 28 Proportional pressure control
Constant pressure
We recommend this control mode in systems with
relatively small pressure losses.
The pump head is kept constant, independent of the
flow in the system.
Fig. 29 Constant pressure control
TM05 2685 1212TM05 3334 1312
H
Q
Q
max
90 %
H
auto_min
H
fac
Q
fac
Setting range
TM05 2448 1212TM05 2449 0312
H
Q
H
set
H
set
2
H
Q