Grundfos CU 301 Manuel D'instructions page 7

1.3 System sizing
To ensure the correct function of the system, it is
important that the pump is of the right type.
During operation, the CU 301 controls the pump
speed within the range from 3,000 rpm to 10,700
rpm, see fig. 6.
It is recommended to follow the guidelines below.
H [ft]
Pump curve
at 3,000 rpm
B
A
Fig. 6 Pump curves at 3,000 rpm and
10,700 rpm
A: Minimum head at no flow.
B: Maximum head at rated flow.
The following must be fulfilled:
• Minimum head at no flow < static head + system
pressure.
Comment: If this is not fulfilled, the pressure may
exceed the pressure set on the CU 301.
• Maximum head at rated flow > dynamic head +
system pressure.
Comment: If this is not fulfilled, the pressure may
fall below the pressure set on the CU 301.
Maximum head at rated flow and minimum head at
no flow can be found in the following sections.
Pump curve
at 10,700 rpm
Q
]
rated flow Q [gpm
1.4 SQE and SQE-NE
Min. head
at 0 gpm,
Pump type
3,000 rpm
5 SQE-90
5 SQE-140
5 SQE-180
5 SQE-230
5 SQE-270
5 SQE-320
5 SQE-360
5 SQE-410
5 SQE-450
10 SQE-110
10 SQE-160
10 SQE-200
10 SQE-240
10 SQE-290
10 SQE-330
15 SQE-70
15 SQE-110
15 SQE-150
15 SQE-180
15 SQE-220
15 SQE-250
15 SQE-290
22 SQE-40
22 SQE-80
22 SQE-120
22 SQE-160
22 SQE-190
22 SQE-220
30 SQE-40
30 SQE-90
30 SQE-130
10 SQE-100 NE
10 SQE-140 NE
10 SQE-180 NE
10 SQE-220 NE
10 SQE-260 NE
10 SQE-300 NE
10 SQE-340 NE
22 SQE-40 NE
22 SQE-80 NE
22 SQE-110 NE
22 SQE-140 NE
22 SQE-180 NE
22 SQE-210 NE
Max. head
at rated flow,
10,700 rpm
[feet] [feet]
12 104
18 161
24 218
31 275
37 332
43 389
49 446
55 503
61 560
12 102
17 158
23 214
29 270
34 326
40 382
10 80
4 121
19 161
24 202
29 242
33 283
38 323
5 35
9 75
14 115
18 155
23 195
27 235
5 31
11 78
16 125
10 96
15 134
20 173
25 212
30 251
34 290
39 329
35 290
39 322
42 353
46 385
50 417
54 448
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