Sanyo ECO G SGP-EW120M2G2W, Technical Data Manual

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System Design
6. Sound-proofing measures
D-27
(3) Sound attenuation by a noise barrier
Sound attenuation of an indoor unit at a reception point behind a noise barrier or building depends on the
frequency and path length difference.
δ
= path length difference
δ
= (A+B)
－
d
●
The barrier should be located as close as possible to the outdoor unit (sound source). (Figure 3)
(Be certain to preserve the required space for air intake and exhaust, service and maintenance.)
●
The barrier should be sufficiently higher than the top of the outdoor unit. (Figure 3)
(However, not more than 1m higher.)
●
The width of the barrier should be at least several times the height, on both sides of the center. Where this is
not possible, the barrier should bend around the unit as shown in Figure 4.
Ex. 2
●
d
B
A
Ex. 3
Ex. 1
Reception point
●
d
B
A
Soun
d b
arri
er
Outdoor unit
●
d
B
A
建
物
●
B
A
Reception point
Bui
ldi
ng
Outdoor unit
Reception point
Building
Outdoor unit
Reception point
Soun
d b
arri
er
Outdoor unit
Figure 2. Diffraction attenuation
1 m or less
Effective area
As close as possible (while maintaining minimum clearances
required for intake, exhaust and servicing of each unit)
Outdoor unit
Soun
d b
arri
er
At least several
times the barrier
height
At least several
times the barrier
height
When adjoining
barriers, longer
than this line.
Figure 3. Sound barrier
Figure 4. Sound barrier