Svantek SV 971A - D.2 Definitions and Formulas of the SLM Result

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
tp
log20tL =
L
d
(t)
Sound level (a function of time) depends on the selected threshold level.
In case None option is selected
( ) ( )
tLtL
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
LtL
LtLtL
tL
for
for
D.2 DEFINITIONS 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)
Lpeak
Lmax, Lmin, L,
Ltm3, Ltm5
Leq,
LE,
LEPd,
SEL,
L(den),
LEPd,
LR15,
LR60
p
w
(t)
all
DOSE
results