Minimum Flow Rate; Electrical Data; Maximum Number Of Starts; Sound Pressure Level - Grundfos CRK Guía De Instalación Y Funcionamiento

6.3 Minimum flow rate

Due to the risk of overheating, the pump must not be
used at flows below the minimum flow rate.
The curve below shows the minimum flow rate as a
percentage of the nominal flow rate in relation to the
liquid temperature.
Q m i n
[ % ]
3 0
2 0
1 0
0
4 0 5 0 6 0 7 0 8 0 9 0 1 0 0 1 1 0 1 2 0
Fig. 5 Minimum flow rate in relation to
temperature

6.4 Electrical data

See motor nameplate.

6.5 Maximum number of starts

Motor size Recommended maximum
[kW] number of starts per hour
0.06 - 0.18
0.25 - 2.2
3-4
5.5 - 11
15-22
30-45

7. Sound pressure level

The table below shows airborne noise emitted by
CRK and MTR pumps with motors fitted by
Grundfos.
t [ ° C ]
100
250
100
50
40
8
L
Motor
[kW]
50 Hz
0.37 50
0.55 50
0.75 50
1.1 52
1.5 54
2.2 54
3.0 55
4.0 62
5.5 60
7.5 60
11 60
15 60
18.5 60
22 66
30 71
37 71
45 71
[dB(A)]
pA
60 Hz
55
53
54
57
59
59
60
66
65
65
65
65
65
70
75
75
75
13