Sound And Vibration Management; Sound; Vibration - Danfoss Maneurop NTZ Series Application Manuallines

Application guidelines

Sound

Vibration

Sound and vibration management

Compressors in operation are one of the sources
of sound and vibration in a refrigeration system.
Both phenomena are closely related.
Sound produced by a compressor is transmit-
ted in every direction by the ambient air, the
mounting feet, the pipework and the refrigerant
in the pipework. The easiest way to reduce the
sound transmitted through ambient air is to fit
Sound power level*
Compressor
at 50 hz dB(A)
model
without hood
NTZ048 72
NTZ068 70
NTZ096 82
NTZ108 76
NTZ136 77
NTZ215 86
NTZ271 86
(*) Operating conditions: R404A, Evap. temp.: -31°F, Cond. temp.: 104°F
The mounting grommets delivered with the com-
pressor should always be used. They will largely
attenuate the compressor vibration transmitted
to the base frame. These rubber grommets have
been selected and calculated in accordance with
the vibration frequencies that are typical for the
compressor. For that reason other grommet types
or brands shall not be used.
The base on which the compressor is mounted
should be sufficiently rigid and of adequate mass
to ensure the full effectiveness of the mounting
an acoustic hood accessory. Because Maneurop®
NTZ compressors are 100% suction gas cooled
and require no external cooling they can be in-
sulated or enclosed in a sound proofing material
lined compartment.
Sound transmitted by mounting feet, pipework
and refrigerant should be treated the same way
as vibration (see next section).
Sound power level*
at 60 Hz dB(A)
with hood without hood
65 75
64 74
74 85
69 80
71 80
80 88
80 88
grommets. The compressor should never be
rigidly mounted to the base frame otherwise
high vibration transmission would occur and the
service life reduced. Suction and discharge lines
must have adequate flexibility in 3 planes. Even-
tually vibration absorbers may be required.
Vibration is also transmitted by the refrigerant
gas. Maneurop® NTZ compressors have built-in
mufflers to reduce pulsation. To further reduce
vibration an extra discharge line muffler can be
installed.
Acoustic
hood
code no.
with hood
68
7755001
68
77
75 7755002
75
81
7755003
81
FRCC.PC.002.A4.22
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