Airwell YEVFD Series, Service Manual

Page: 25 / 92

11. Noise Level
(1) Testing illustration
(2) Testing condition:
a. Unit running in the nominal condition
b. Test in the semi-anechoic chamber
c. Noise level varies from the actual factors such as room structure, etc.
(3) Octave band level
1
m
A
Front
Octave band sound pressure level dB (A)
Octave band center frequency Hz
Octave band sound pressure level dB (A)
Octave band center frequency Hz
8000 4000 2000 1000 500 250 125
70
60
50
40
30
20
10
NC-60
NC-50
NC-40
NC-30
NC-20
H
Limit of
audible
continuous
noise
63 8000 4000 2000 1000 500 250 125
70
60
50
40
30
20
10
NC-60
NC-50
NC-40
NC-30
NC-20
H
Limit of
audible
continuous
noise
63
8000 4000 2000 1000 500 250 125
70
60
50
40
30
20
10
NC-60
NC-50
NC-40
NC-30
NC-20
H
63
Limit of
audible
continuous
noise
Octave band sound pressure level dB (A)
Octave band center frequency Hz
AW-YEVFD220-H16
AW-YEVFD280-H16
AW-YEVFD335-H16
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