Grundfos NB Series, Инструкция по установке и эксплуатации

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3.3 Impeller diameter
At the customer’s request, the impeller diameter may have been
changed to allow the pump to match a specified duty point. This
means that the actual impeller diameter differs from the standard
diameters stated in sales catalogues, data sheets, etc.
The actual impeller diameter can be found on the pump name-
plate.
3.4 Pumped liquids
Clean, thin, non-explosive liquids without solid particles or fibres.
The pumped liquid must not attack the pump materials chemi-
cally.
When pumping liquids with a density and/or viscosity higher than
that of water, motors with correspondingly higher outputs must be
used, if required.
O-rings and the mechanical shaft seal chosen must be suitable
for the liquid to be pumped.
Special shaft seals may be required if the pump is used for pump-
ing treated water at temperatures above 80°C containing addi-
tives to prevent system corrosion, calcareous deposits, etc., for
instance in heating and ventilating systems.
Another type of shaft seal may also be required for the pumping
of glycol-containing liquids.
For heating systems, the water quality should meet VDI 2035.
Contact Grundfos for further information.
4. Technical data
4.1 Ambient temperature
The ambient temperature and the installation altitude are impor-
tant factors for the motor life, as they affect the life of the bearings
and insulation system.
Maximum ambient temperature:
• EFF2 motors: +40°C.
• EFF1 motors: +60°C.
If the ambient temperature e40°C (+60°C), or the motor
is installed more than 1000 m (3500 m) above sea level, the
motor must not be fully loaded due to the low density and conse-
quently low cooling effect of the air. In such cases, it may be nec-
essary to use a motor with a higher output.
Fig. 5 Motor P2 in relation to temperature/altitude
4.2 Liquid temperature
–25°C to +140°C.
The maximum liquid temperature is stated on the pump name-
plate. It depends on the shaft seal chosen.
For pump housing of cast iron EN-GJL-250 local regulations may
not allow liquid temperatures above +120°C.
4.3 Operating pressure
The maximum operating pressure is stated on the nameplate.
NB:
Maximum 1.6 MPa (16 bar).
DN 200: 1 MPa (10 bar).
NBG:
Maximum 1.6 MPa (16 bar).
4.4 Min. inlet pressure
According to the NPSH curve of the pump (see page 477) + a
safety margin of minimum 0.5 m head.
The procedure for the calculation of the minimum inlet pressure is
shown in
13. Calculation of minimum inlet pressure .
4.5 Maximum inlet pressure
The actual inlet pr pressure when the pump is running
against a closed valve must always be lower than the maximum
operating pressure.
4.6 Minimum flow rate
The minimum flow rate must be at least 10% of the maximum flow
rate. The flow rate and head are stated on the pump nameplate.
4.7 Maximum flow rate
The maximum flow rate must not exceed the values stated for the
individual pump on page 463, as otherwise there is a risk of for
instance cavitation and overload.
4.8 Electrical data
See the motor nameplate.
4.9 Weight
See label on the packing.
4.10 Sound level
See table on page 461.
The values stated are maximum values, including the upper toler-
ance of 3 dB according to ISO 4871.
4.11 Pump speed relative to material and size
Fig. 6 Maximum permissible speed
For stainless steel pumps (1.4408/1.4517) there is no limit in the
range shown.
TM
02
85
51
05
04
20 25 3 0 3 5 40 45 50 55 60 65 70 75 80
50
60
70
80
90
100
[%]
P2
EFF 2
EFF 1
t [°C]
1000 2250 3 500 4750 m
TM
03
41
09
18
06
1200 1600 2000 2400 2800 3 200 3 600 min
-1
200
250
3 00
3 50
400
450
500
550
600
650
CuSn10
EN-GJL-200
Ø [mm]