Grundfos CRN Series Product Guide

Selection and sizing
CR, CRI, CRN, CRE, CRIE, CRNE
25
How to read the curve charts
Fig. 27 How to read the curve charts
Guidelines to performance curves
The guidelines below apply to the curves shown on the
following pages:
1. The motors used for the measurements are stand-
ard motors (ODP, TEFC or MLE).
2. Measurements have been made with airless water
at a temperature of 68 °F.
3. The curves apply to a kinematic viscosity of
 = 1 mm
2
/s (1 cSt).
4. Due to the risk of overheating, the pumps should not
be used at a flow below the minimum flow rate.
5. The QH curves apply to actual speed with the motor
types mentioned at 60 Hz.
The curve below shows the minimum flow rate as a
percentage of the nominal flow rate in relation to the
liquid temperature. The dotted line shows a CR pump
fitted with an air-cooled top assembly.
Fig. 28 Minimum flow rate
TM02 0039 1303
0 20 40 60 80 100 120 140 160 180 200
Q [US GPM]
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
850
900
950
1000
[ft]
H
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
850
900
950
1000
[ft]
H
0
20
40
60
80
100
120
140
160
180
200
220
240
260
280
300
[m]
H
0 5 10 15 20 25 30 35 40 45
Q [m/h ]
CR(E) 32
2-pole, 60 Hz
CRN(E) 32
-11-2
-10
-1
-1-1
-10-2
-2
-2-1
-2-2
-3
-3-2
-4
-4-2
-5
-5-2
-6
-6-2
-7
-7-2
-8
-8-2
-9
-9-2
0 20 40 60 80 100 120 140 160 180 200
Q [US GPM]
0
1
2
3
4
P2
[hp]
0
20
40
60
80
[%]
E
0
1
2
P2
[kW ]
P2 1/1
P2 2/3
E
0
10
20
30
NPSH
[ft]
0
10
20
30
[ft]
H
0
4
8
[m]
H
NPSHR
Number of stages.
First figure: number of
stages;
second figure: number of
reduced-diameter impellers.
The eff curve shows the
efficiency of the pump.
The eff curve is an average
curve of all the pump types
shown in the chart.
The efficiency of pumps
with reduced-diameter
impellers is approx. 2 %
lower than the eff curve
shown in the chart.
Pump type, number
of poles and frequency.
QH curve for the individual
pump. The bold curves
indicate the recommended
performance range for
best efficiency.
The power curves indicate
pump input power per stage.
Curves are shown for
complete (1/1) and for
reduced-diameter (2/3)
impellers.
The NPSHR curve is an
average curve for all the
variants shown. When
sizing the pumps, add a
safety margin of at
least 2.0 feet.
TM02 7538 3703
40 60 80 100 120 140 160 180
t [°F]
0
10
20
30
Qmin
[%]
40 60 80 100 120 140 160 180
t [°C]
140 176 212 248 284 320 356104

Grundfos CRN Series Specifications

General

Pump Type	Centrifugal, multistage
Material	Stainless steel (AISI 304 or 316)
Applications	Water supply, pressure boosting, industrial processes
Impeller Material	Stainless steel (AISI 304 or 316)
Connections	Flanged or threaded
Speed	2900 rpm
Temperature Range	-10°C to +120°C
Inlet/Outlet Size	DN 25 to DN 100