Grundfos magna3 User Manual

Functions
MAGNA3
4
24
Flow estimation accuracy
The internal sensor estimates the difference in
pressure between the inlet and outlet port of the pump.
The measurement is not a direct differential-pressure
measurement, but by knowing the hydraulic design of
the pump, you can estimate the differential pressure
across the pump. The speed and power are also used
to give a direct estimation of the current duty point of
the pump.
The calculated flow rate has an accuracy specified as
± xx % of Q
max
. The less flow through the pump, the
less accurate the reading will be. The typical accuracy
of the flow reading is ± 5 % of the specific pump’s
maximum flow. In extreme cases, such as closed valve
operation, the accuracy can be up to ± 10 % of the
maximum flow.
See also Heat energy monitor, page 26.
Example:
Fig. 31 Q
max
1. MAGNA3 65-60 has a Q
max
of 40 m
3
/h. A typical 5
% accuracy means 2 m
3
/h inaccuracy of Q
max
. ± 2
m
3
/h.
2. This accuracy is valid for the entire QH area. If the
pump indicates 10 m
3
/h, the measurement is 10 ± 2
m
3
/h.
3. The flow rate can be 8-12 m
3
/h.
4. Note: Use of a water/ethylene glycol mixture will
decrease the accuracy.
TM05 2448 5111
H
Q
Max.
Min.
Q
max

Grundfos magna3 Specifications

General

Liquid Temperature Range	-10°C to +110°C
Max Operating Pressure	16 bar
Type	Circulator Pump
Series	MAGNA3
Operating Temperature Range	-10°C to +110°C
Ambient Temperature Range	0°C to +40°C
Protection Class	IPX4D
Power Supply	1 x 230 V, 3 x 230 V, 3 x 400 V
Control Mode	Constant pressure, Proportional pressure
Communication	Modbus RTU
Pump Housing	Cast Iron
Impeller	Composite
Enclosure Class	X4D
Approvals	CE, EAC
Connection	Flange
Weight	Varies depending on model
Power Consumption	Varies depending on model