Svantek SV 200A, Руководство пользователя

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196 SV 200A User Manual
L(A/C/Z)(S/F/I) Time weighted sound level (SPL) expressed
at observation time, expressed in dB, for
frequency weightings A, C, Z and time
weightings F, S, I symbols are LAF, LAS,
LCF, LCS etc.
( )






=

2
0
2
W
p
t p
log 10 L
L(A/C/Z)eq Time averaged equivalent continuous sound
level (
Leq ) expressed in dB, for frequency
weightings A, C, Z symbols are LAeq, LCeq
and LZeq. In principle time weighting is not
involved in a determination of time averaged
sound level. Time-averaged sound level is
calculated for current time period of the
measurement (
T ).
( ) ( )








=

T
0
2
0
dt p t r
T
1
log 10 Leq
L(A/C/Z)E Sound Exposure Level (SEL) expressed in
dB, for frequency weightings A, C, Z,
symbols are LAE, LCE and LZE. SEL is
essentially the subset of the
Leq result. Its
value is equal to the Leq result referred to the
integration time equal to one second (so, for
the Integration time equal to 1 s, SEL is
always equal to
Leq ).
( )
( )
s 1
T
log 10 Leq dt p t r log 10 SEL
T
0
2
0
+ =








=

L(den) Only one result from: Ld , Le , Ln , Lde , Len , Lnd , and Lden is available in the
instrument. It depends on the day and night time in which the measurement was
performed. Day and night time depend on the
<Day Time Limits> option ( 6h-18h or
7h-19h ).
If <6h-18h> option is selected for the < Day Time Limits> in the instrument then:
T
d
(day-time) starts from 6 am and ends at 6 pm,
T
e
(evening-time) starts from 6 pm and ends at 10 pm,
T
n
(night-time) starts at 10 pm and ends at 6 am.
If <7h-19h> option is selected for the < Day Time Limits> in the instrument then:
T
d
(day-time) starts from 7 am and ends at 7 pm,
T
e
(evening-time) starts from 7 pm and ends at 11 pm,
T
n
(night-time) starts at 11 pm and ends at 7 am.
Ld Ld is calculated for: T
d
≠ 0,
T
e
= 0, T
n
= 0.
( )
( )








=

d
T
2
0 W
d
dt p t r
T
1
log 10 Ld
Le Le is calculated for: T
d
= 0, T
e
≠ 0,
T
n
= 0.
( )
( )








+ =

e
T
2
0 W
e
dt p t r
T
1
log 0 1 dB 5 Le