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THE
ENERGY
FAMILY
(C) IDM Energiesysteme GmbH
General description
Installation instructions TERRA AL Twin
16
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distance [m]
Soundpressure-level-reduction [dB(A)]
Placement and Installation
P
lac
ement
a
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d
In
sta
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tion
4.9. Sound pressure reduction when sound radiation on a facade
Example 1:
The sound pressure level for the TERRA AL 17 have to be calculated in 5 m distance (on a facade):
Sound power level AL 17 - Sound pressure level reduction ==> Sound pressure level in 5 m
66.9 dB(A) - 19.0 dB(A) =
47.9 dB(A)
Example 2:
The sound pressure level for the TERRA AL 32 have to be calculated in 10 m distance (on a facade):
Sound power level AL 32 - Sound pressure level reduction ==> Sound pressure level in 5 m
75.8 dB(A) - 25.0 dB(A) =
50.8 dB(A)
