Application guidelines
41
FRCC.PC.021.A5.22
Sound and vibration management
Running sound level
Stopping sound level
PSH compressors are equipped with a discharge
valve which closes at compressor shut down
and thus prevents the compressor from running
backwards.
This reduces the stopping sound to a metallic
click caused by the closing valve.
When the pressure difference or gas flow at shut
down should be very low, this can delay the
discharge valve from closing and lead to a longer
noise duration.
During start-up transients it is natural for
the compressor sound level to be slightly
higher than during normal running. PSH scroll
compressors exhibit very little increased start-up
transient sound. If a compressor is miswired,
the compressor will run in reverse. Reverse
compressor rotation is characterized by an
objectionable sound. To correct reverse rotation,
disconnect power and switch any two of the
three power leads at the unit contactor.
Never switch leads at the compressor terminals.
Starting sound level
Bottom insulation delivered together with
the compressor incorporates sound proofing
materials and offer excellent high and low
frequency attenuation.
As an option, compressor acoustic hoods have
been developed to meet specific extra-low noise
requirements.
Sound power
dB(A)
Sound power dB(A)
50Hz
60Hz
Compr
essor
PSH051
84
87.5
PSH064
87
90
PSH077
84
88.5
Tandem
PSH104
87
90.5
PSH115
88.8
91.9
PSH130
90
93
PSH128
87
91
PSH141
88.8
92.3
PSH154
87
91.5
Tr
io
PSH153
88.8
92.3
PSH152
91.8
94.8
PSH231
88.8
93.3