Sanyo ECO G SGP-EW120M2G2W, Технические данные инструкция

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System Design
6. Sound-proofing measures
D-26
(1) Installation location and sound-proofing measures
If no suitable installation location is available and it is necessary to install in a confined location where there
are houses, offices or other buildings nearby, it may be necessary to provide sound barrier walls, sound
absorption chambers or other secondary sound-proofing measures.
Secondary sound-proofing measure include:
•
Attenuation over distance
•
Sound-proofing with noise barriers
•
Sound-proofing using sound absorbing chambers
•
Sound-proofing by vibration isolation (anti-vibration pads, flexible couplings, etc.)
The following criteria are from Tokyo Pollution Prevention Regulations.
Criteria for everyday sound levels
Ordinary standards
Special
standards
Morning Daytime Evening Night
Condition
Area type
Sound
level
(phon)
Time
Sound
level
(phon)
Time
Sound
level
(phon)
Time
Sound
level
(phon)
Time
Near schools
and hospitals
(approx. 50m)
Type 1
Residential and
school areas, etc.
40 45 40 40 Same as at left
Type 2
Residential and
undesignated
areas
45 50
8 AM to
7 PM
45
7 PM to
11 PM
45
Type 3
Commercial, light
industrial, industrial
areas
55 60 55 50
11 PM to
6 AM
Type 4
Shopping areas
and specially
designated areas
60
6 AM to
8 AM
70
8 AM to
8 PM
60
8 PM to
11 PM
55
At least 5 phon
lower than at left
(2) Attenuation of sound over distance
The figure at the right shows sound attenuation over
distance. (Figure 1)
Operating sound is measured 1m from its source.
Example. For a type 280 outdoor unit, the sound level in
the 50-Hz range at 3m distance is specified as
56 dB(A). In Figure 1, follow the 3m distance
line downwards to where it crosses the slope
(a), and then horizontally to point (b) at the left
to find the attenuation of 6.8 dB(A).
Therefore, 56 – 6.8 = 49.2 dB(A)