14
8.
Sound pressure level
Unit
Air
Air outlet duct
Air return duct
Outlet side
1.4m
Sound level meter
Testing position just below the central of the unit
evl
av
lor
tn
o
C
(2) Testing condition:
a. Unit running in the standard condition
b. Test in the semi-anechoic chamber
c. Noise level varies from the actual factors such as room structure, etc.
(1) Testing illustrate:
10
20
30
40
50
60
70
63
125
250
500
1000
2000 4000 8000
MVAH018MV2AA
10
20
30
40
50
60
70
63
125
250
500
1000
2000 4000 8000
8000
4000
2000
1000
500
250
125
63
70
60
50
40
30
20
10
MVAH030MV2AA
MVAH024MV2AA
Octave band center frequency (HZ)
Octave band center frequency (HZ)
Octave band center frequency (HZ)
Octave band sound pressure level dB
Octave band sound pressure level dB
Octave band sound pressure level dB
Limit of
audible
continuous
noise
Limit of
audible
continuous
noise
Limit of
audible
continuous
noise
NC-60
NC-50
NC-40
NC-30
NC-20
NC-60
NC-50
NC-40
NC-30
NC-20
NC-60
NC-50
NC-40
NC-30
NC-20
H
M
L
H
M
L
H
M
L
8000
4000
2000
1000
500
250
125
63
63
63
63
63
63
63
63
70
60
50
40
30
20
10
MVAH036MV2AA
Octave band center frequency (HZ)
Octave band sound pressure level dB
Limit of
audible
continuous
noise
NC-60
NC-50
NC-40
NC-30
NC-20
H
M
L
8000
4000
2000
1000
500
250
125
63
63
63
63
63
63
63
63
70
60
50
40
30
20
10
MVAH042MV2AA
Octave band center frequency (HZ)
Octave band sound pressure level dB
Limit of
audible
continuous
noise
NC-60
NC-50
NC-40
NC-30
NC-20
H
M
L
MVAH048MV2AA
Octave band center frequency (HZ)
10
20
30
40
50
60
70
63
63
63
63
63
63
63
63
125
250
500
1000
2000 4000 8000
Octave band sound pressure level dB
Limit of
audible
continuous
noise
NC-60
NC-50
NC-40
NC-30
NC-20
H
M
L
