Grundfos ALPHA+ Series User Manual

11
Note: The night-time duty function is deacti-
vated if the selector switch has been set to
speed I, II or III.
6.4 Pump control
During operation, the pump head will be
changed according to the principle "propor-
tional-pressure control". In this control mode,
the pump performance, and consequently the
power consumption, is adjusted to the actual
water requirement.
An example is shown in
s. In the example, the
pump duty point is changed from (1) to (2) be-
cause of a changed system characteristic
(thermostatic valves are closed) and conse-
quently a lower water requirement.
7. Technical data
Supply voltage: 1 x 230 V –10%/+6%, 50 Hz,
PE.
Motor protection: The pump requires no exter-
nal motor protection.
Enclosure class: IP 42.
Insulation class: F.
Relative air humidity: Maximum 95%.
Ambient temperature: 0°C to +40°C.
Temperature class: TF110 to CEN 335-2-51.
Liquid temperature: +2°C to +110°C.
Pumps in domestic hot-water systems:
+15°C to +60°C.
To avoid condensation in the terminal box and
the stator, the pumped liquid temperature must
always be higher than the ambient tempera-
ture. See the table:

Grundfos ALPHA+ Series Specifications

General

Max. Operating Pressure	10 bar
Frequency	50/60 Hz
Protection Class	IP42
Pump Type	Circulation Pump
Power Supply	230 V
Power Consumption	5-45 W
Temperature Range	2°C to 110°C
Connection Size	1"
Material	Cast iron
Connection Type	Threaded
Impeller Material	Composite