Sound and vibration management
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
Sound power
dB(A)
Sound power dB(A)
50Hz
60Hz
PSH019
75
77
PSH023
76.5
78.5
PSH026
77.5
79
PSH030
77.5
79
PSH034
79
81
PSH039
78
80
Sound Power and attenuation are given at -7/50°C condition.
Running 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.
Compressor acoustic hoods have been
developed to meet specific extra-low noise
requirements.
Stopping sound level
28
FRCC.PC.022.A4.02
Application Guidelines
