Svantek SV 971A, Руководство пользователя

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SV 971A User Manual
– Appendixes
285
L
T
Threshold sound level set in the Threshold Level parameter. The available values are
as follows: None , 60dB up to 90dB in 5 dB steps.
L
C
Criterion sound level set in the Criterion Level parameter. The available values are from
60dB up to 90dB in 5 dB steps.
L(t)
Sound level (a function of time) measured
with the selected time constant (
Impulse ,
Fast or Slow ) and the weighting filter (equal
to A , C or Z )
( )
( )
0
W
p
t p
log 20 t L
=
L
d
(t) Sound level (a function of time) depends on the selected threshold level.
In case None option is selected
( ) ( )
t L t L
d
=
In other cases (when Threshold Level is
not set to none and equal to 60 dB
… or up
to 90 dB )
( )
( ) ( )
( )



  −

=
T
T
d
L t L
L t L t L
t L
for
for
D.2 D
EFINITIONS AND FORMULAS OF THE
SLM
RESULT
The instrument calculates the sound measurement results for three profiles. The calculation flow diagram for
one profile is presented below:
OVL Percentage of the overloaded input signal, which occurred during the current time period
of the measurement (
T )
p
2
wτ
(t)
τ = Fast
τ = Slow
τ = Imp
p
w
(t)
p(t)
p
2
w
(t)
L
peak
L
max,
L
min, L,
L
tm3,
L
tm5
L
eq,
LE,
LEPd,
SEL,
L(den),
LEPd,
LR15,
LR60
p
w
(t)
all
DOSE
results