UB USER INSTRUCTIONS ENGLISH 71569247 07-04
Page 9 of 32
®
1.9 Noise level
When pump noise level exceeds 85 dB(A) attention
must be given to prevailing Health and Safety
Legislation, to limit the exposure of plant operating
personnel to the noise. The usual approach is to
control exposure time to the noise or to enclose the
machine to reduce emitted sound. You may have
already specified a limiting noise level when the
equipment was ordered, however if no noise
requirements were defined then machines above a
certain power level will exceed 85 dB(A). In such
situations consideration must be given to the fitting of
an acoustic enclosure to meet local regulations.
Pump noise level is dependent on a number of
factors - the type of motor fitted, the operating
capacity, pipework design and acoustic
characteristics of the building. Typical sound
pressure levels measured in dB, and A-weighted are
shown in the table below.
The figures are indicative only, they are subject to a
+3 dB tolerance, and cannot be guaranteed.
The values are based on the noisiest ungeared
electric motors that are likely to be encountered.
They represent sound pressure levels at 1 m (3.3 ft)
from the directly driven pump, for "free field over a
reflecting plane".
If a pump unit only has been purchased, for fitting
with your own driver, then the "pump only" noise
levels from the table should be combined with the
level for the driver obtained from the supplier. If the
motor is driven by an inverter it may show an
increase in noise level at some speeds. Consult a
Noise Specialist for the combined calculation.
For units driven by equipment other than electric
motors or units contained within enclosures, see the
accompanying information sheets and manuals.
Typical sound pressure level, dBA, L
pA
at 1 m reference 20 µPa (
L
wA
sound power 1 pW where L
pA
> 85 dBA
)
3550 r/min
2900 r/min
1750 r/min
1450 r/min
Motor size
and speed
kW (hp)
Pump and
motor
dBA
Pump
only
dBA
Pump and
motor
dBA
Pump
only
dBA
Pump and
motor
dBA
Pump
only
dBA
Pump and
motor
dBA
Pump
only
dBA
<0.55 (<0.75)
71
(88)
66
(83)
64
(81)
62
(79)
64
(81)
62
(79)
63
(80)
62
(79)
0.75 (1)
74
(91)
66
(83)
67
(84)
62
(79)
67
(84)
62
(79)
63
(80)
62
(79)
1.1 (1.5)
74
(91)
68
(85)
67
(84)
64
(81)
67
(84)
64
(81)
65
(82)
64
(81)
1.5 (2)
77
(94)
70
(87)
70
(87)
66
(83)
70
(87)
66
(83)
66
(83)
66
(83)
2.2 (3)
78
(95)
72
(89)
71
(88)
68
(85)
71
(88)
68
(85)
68
(85)
68
(85)
3 (4)
81
(98)
74
(91)
74
(91)
70
(87)
74
(91)
70
(87)
70
(87)
70
(87)
4 (5)
82
(99)
75
(92)
75
(92)
71
(88)
75
(92)
71
(88)
71
(88)
71
(88)
5.5 (7.5)
90 (
107
)
77
(94)
83
(100)
73
(90)
76
(93)
73
(90)
72
(89)
71
(88)
7.5 (10)
90 (
107
)
78
(95)
83
(100)
74
(91)
77
(94)
74
(91)
73
(90)
72
(89)
11 (15)
91 (
108
)
80
(97)
84
(101)
76
(93)
78
(95)
76
(93)
74
(91)
73
(90)
15 (20)
92 (
109
)
83
(100)
85 (
102
)
79
(96)
80
(97)
79
(96)
76
(93)
75
(92)
18.5 (25)
92 (
109
)
83
(100)
85 (
102
)
79
(96)
80
(97)
79
(96)
76
(93)
75
(92)
22 (30)
92 (
109
)
83
(100)
85 (
102
)
79
(96)
81
(98)
79
(96)
77
(94)
75
(92)
30 (40)
100 (
117
)
85 (
102
)
93 (
110
)
81
(98)
84
(101)
80
(97)
80
(97)
76
(93)
37 (50)
100 (
117
)
86 (
103
)
93 (
110
)
82
(99)
84
(101)
80
(97)
80
(97)
76
(93)
45 (60)
100 (
117
)
87 (
104
)
93 (
110
)
83
(100)
84
(101)
80
(97)
80
(97)
76
(93)
55 (75)
100 (
117
)
88 (
105
)
95 (
112
)
84
(101)
86 (
103
)
81
(98)
82
(99)
77
(94)
75 (100)
100 (
117
)
90 (
107
)
95 (
112
)
86 (
103
)
88 (
105
)
81
(98)
83
(100)
78
(95)
90 (120)
100 (
117
)
90 (
107
)
95 (
112
)
86 (
103
)
90 (
107
)
81
(98)
85 (
102
)
78
(95)
110 (150)
100 (
117
)
91 (
108
)
95 (
112
)
87 (
104
)
91 (
108
)
83
(100)
86 (
103
)
79
(96)
150 (200)
101 (
118
)
92 (
109
)
96 (
113
)
88 (
105
)
91 (
108
)
83
(100)
86 (
103
)
79
(96)
200 (270)
①
①
①
①
①
83
(100)
①
80
(97)
300 (400)
-
-
-
-
①
84
(101)
①
81
(98)
500 (670)
-
-
-
-
①
85 (
102
)
①
83
(100)
1000 (1300)
-
-
-
-
①
86 (
103
)
①
86 (
103
)
1500 (2000)
-
-
-
-
①
90 (
107
)
①
88 (
105
)
①
Motors in this range are generally job specific and noise levels should be calculated based on actual equipment installed.
For 960 r/min reduce 1450 r/min values by 5 dBA.
