Model 90 Quantifier Sound Level Meter
Page 6
Please read. A note is a hint or advice that helps you make best use of the
equipment and accessories.
Section 1 Introduction
Main Features
Measurement Functions
The measurement functions that can be provided by the MODEL 90 depend upon the
options that have been fitted. If the instrument has been fitted with the 1:1 Octave
Band or the 1:3 Octave Band filters, these measurements will be available.
Listed below is a summary of the measurements that can be provided by the basic
Broadband instrument, and by the addition of the 1:1 Octave Band or the 1:3 Octave
Band filters.
If the Auto Repeat function is used, the MODEL 90 can be made to repeat the
broadband measurement up to 999 times. See page 21 for details of setting the auto
repeat function. The instrument can also be configured to synchronise the
measurement start time with the instrument clock. See page 21 for details of the Auto
Synchronise function.
Broadband Measurement Mode
In Broadband Mode, the instrument stored the overall values such as L
Aeq
, L
AFmax
and
Ln’s as well as storing a noise profile, or Time History, during each measurement.
The MODEL 90 instruments can store up to 1,300 Broadband Measurements which can
be of any length, up to a maximum of 99 hours per measurement. With each
measurement is stored a noise profile which consists of 1 second Leq samples, with up
to a maximum of 11 days of Noise Profile being available.
Function
Frequency
Weighting
Displayed as
Maximum
value
Minimum
value
Sound Level with Fast Time
Weighting
A
L
AF
L
AFmax
L
AFmin
C
L
CF
L
CFmax
L
CFmin
Z
L
ZF
L
ZFmax
L
Zfmin
Sound Level with Slow Time
Weighting
A
L
AS
L
ASmax
L
ASmin
C
L
CS
L
CSmax
L
CSmin
Z
L
ZS
L
ZSmax
L
Zsmin
Sound Level with Impulse
Time Weighting
A
L
AI
L
AImax
L
AImin
C
L
CI
L
CImax
L
CImin
Z
L
ZI
L
ZImax
L
ZImin
Equivalent Continuous Sound
Pressure Level with
integration time t
A
L
Aeqt
-
-
C
L
Ceqt
-
-
Z
L
Zeqt
-
-
Sound Exposure Level (SEL)
A
L
AE
-
-
C
L
CE
-
-
Z
L
ZE
-
-
Peak Sound Pressure
C
LCpeak
-
-
Takt Maximum Sound Level
DIN 45641 (L
AFTeq
)
A
LAFTeq
-
-
Impulse Weighted Equivalent
A
LAIeqt
-
-
i
