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

SOUND AND VIBRATION MANAGEMENT

Sound

Vibration

22
Compressors in operation are one of
the sources of sound and vibration in
Sound produced by a compressor is
transmitted 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 ambi-
ent air is to fi t an acoustic hood acces-
sory. Because Maneurop® NTZ com-
Sound power level*
Compressor
at 50 hz dB(A)
model
without hood
NTZ048 72
NTZ068 70
NTZ096 78
NTZ108 76
NTZ136 77
NTZ215 84
NTZ271 84
(*) Operating conditions: R404A, Evap. temp.: -35°C, Cond. temp.: 40°C, 400 V / 50Hz
The mounting grommets delivered
with the compressor should always
be used. They will largely attenuate
the compressor vibration transmit-
ted to the base frame. These rubber
grommets have been selected and
calculated in accordance with the vi-
bration 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 suffi ciently rigid
and of adequate mass to ensure the
full eff ectiveness of the mounting
a refrigeration system. Both phenom-
ena are closely related.
pressors are 100% suction gas cooled
and require no external cooling they
can be insulated or enclosed in a sound
proofi ng 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
71 82
69 80
71 80
78 88
78 88
grommets. The compressor should
never be rigidly mounted to the base
frame otherwise high vibration trans-
mission would occur and the service
life reduced. Suction and discharge
lines must have adequate fl exibility in
3 planes. Eventually vibration absorb-
ers may be required.
Vibration is also transmitted by the
refrigerant gas. Maneurop® NTZ com-
pressors have built-in muffl ers to re-
duce pulsation. To further reduce vi-
bration an extra discharge line muffl er
can be installed.
Acoustic
hood
code no.
with hood
68
7755001
68
74
75 7755002
75
81
7755003
81