Pressure; Sound Level; Sound Level Of A Pump Without Drive - Johnson Pump TG GS2-25 Instruction Manual

3.6

Pressure

Differential pressure or working pressure (p) is the pressure on which the pump normally
operates. TopGear GS-line has the maximum differential pressure at 10 bar.
TopGear GS-range
The hydrostatic test pressure is 1.5 times the differential pressure i.e.:
TopGear GS-line has the hydrostatic test pressure at 15 bar.
Following figure gives a graphical presentation of the several kinds of pressures.
3.7

Sound level

3.7.1

Sound level of a pump without drive

Sound pressure level (L
The following table gives an overview of the A-weightened sound pressure level, L
a pump without drive, measured according to ISO3744 and expressed in decibels dB(A).
The reference sound pressure is 20µPa.
The values depend on the position from where one measures and were therefore measured at the
front of the pump, at distance of 1 meter from the pump cover and were corrected for background
noise and reflections.
The values listed are the highest measured values under following operating conditions.
• working pressure: up to 10 bar.
• pumped medium: water, viscosity = 1 mPa.s
• —% n
TG GS Pump size
2-25
3-32
6-40
15-50
23-65
58-80
86-100
185-125
Sound power level (L
The sound power L
sound levels of machines. It is the sound pressure Lp that acts on a surrounding surface at distance
of 1 meter.
L = L
WA pA
The A-weightened sound power level L
The reference sound power is 1 pW (= 10
distance of 1 metre from the pump, expressed in dB(A) and is listed in the last column of above
table.
A.0500.501 – IM-TGGS/05.01 EN (03/2013)
)
pA
= — % maximum shaft speed
max
n (min-1)
max
25% n
max
1800 51
1800 53
1800 57
1500 61
1500 63
1050 67
960 69
750 71
)
WA
is the power emitted by the pump as sound waves and is used to compare
W
+ Ls
Lpa (dB(A))
50%n 75%n 100%n
max max
62 68 72
65 72 76
68 76 80
72 79 83
75 81 85
79 85 89
80 86 90
82 87 91
is also expressed in decibels dB(A).
WA
W). L is the logarithm of the surrounding surface at
-12
S
emitted by
pA
Ls (dB(A))
max
9
9
9
9
10
10
11
11
17