16
ALR 110F – 150F
Product Manual ALR2-3
Sound Data
Table 7, ALR 110F - 150F, Sound Pressure
Octave Band Sound Pressure Levels Per ARI Standard 370 (dB)
ALR
Unit Size
63 hz
125 hz
250 hz
500 hz
1000 hz
2000 hz
4000 hz
8000 hz
Overall "A"
Weighted
110
65
68
69
66
62
60
57
53
68.5
120
65
68
69
66
62
60
57
53
68.5
130
66
69
70
67
63
61
58
54
69.5
135
66
69
70
67
63
61
58
54
69.5
140
67
70
71
68
63
61
59
54
70.0
145
67
70
71
68
63
61
59
54
70.0
150
68
71
72
69
64
62
59
55
71.0
NOTES
1.
Based on Uniform Spherical Radiation, Q=1
2.
Sound pressure at 30 feet from unit.
Table 8, ALR 110F - 150F, Sound Power
Octave Band Sound Power Levels Per ARI Standard 370 (dB)
ALR
Unit Size
63 hz
125 hz
250 hz
500 hz
1000 hz
2000 hz
4000 hz
8000 hz
Overall "A"
Weighted
110
95
98
99
96
92
90
87
83
98.5
120
95
98
99
96
92
90
87
83
98.5
130
96
99
100
97
93
91
89
84
99.5
135
96
99
100
97
93
91
89
84
99.5
140
97
100
101
98
93
91
89
84
100.0
145
97
100
101
98
93
91
89
84
100.0
150
98
101
102
99
94
92
89
85
101.0
Per ARI 370 - Sound Rating of Large Outdoor Refrigerating and Air-Conditioning Equipment
Sound levels can be as important as unit cost and efficiency, and must be addressed before the start
of any development program. Efforts by McQuay Design Engineers to design chillers that are
sensitive to the sound requirements of the market have paid off.
Background Information
Sound is a vibration in an elastic medium and is essentially a pressure and particle displacement
phenomena. A vibrating body produces compression waves and as the waves are emitted from the
vibrating body, molecules are ultimately compressed. These waves are transmitted through gases,
liquids, or solids-anything that is elastic or viscous.
The sound data provided in this section is presented with both sound pressure (Q=1 and 30 feet from
unit) and sound power levels. Sound power is the total sound energy radiated by a source per unit of
time integrated over the surface through which the sound is radiated. Sound power is a calculated
quantity and cannot be measured directly like sound pressure. Sound power is not dependent on the
surrounding environment or distance from the source, as is sound pressure.
Sound pressure varies with the distance from the source and is dependent on its surroundings. For
example, a brick wall located 10 feet from a unit will affect the sound pressure measurements differently
than a brick wall at 20 feet. Sound pressure is measured in decibels (dB), which is a dimensionless
ratio (on a logarithmic scale) between measured sound pressure and a reference sound pressure level.
Sound Pressure Levels - Full Load
Sound pressure tables give the overall "A" weighted sound pressure levels which are considered
typical of what may be measured in a free field with a hand held sound meter, in the absence of any
nearby reflective surfaces. The sound pressure levels (Table 7) are measured at 30 feet from the side
of the unit at 100% unit load, no reflecting walls Q=1, and ARI conditions, 95°F (35°C) ambient air
temperature and 54/44°F (12/7°C) evaporator water temperatures for air-cooled units.
Содержание ALR 110F
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