Larson Davis 824 User Manual

9/29/09 System 824 Views 5-25
Current SLM and Overall SLM Views
Current SLM clears and starts over
when the R Reset button is pressed
while running. Overall SLM does not
clear during a reset, but continues
accumulating data.
The System 824 contains two independent data buffers that
can accumulate data separately. In essence, the instrument
becomes two sound level meters in one. The data in the
primary buffer is referred to as the “overall” measurement,
while data in the secondary buffer is referred to as the
“current” measurement.
The
uand darrow keys can be
used to cycle between the Current
SLM, Overall SLM, Exposure, Ln
Centiles, and Stats views.
The Current SLM and Overall SLM Views have five
common displays which can be cycled through using
the
randlarrow keys. Since these displays are identical they
will be discussed together. These displays are categorized as
follows:
a) SPL
b) Times
c) Min/Max
Daily
History
Ldn, CNEL, Leq 24, LPK-I, LPK-II, Ln’s
(if desired), Lmax and Lmin are
calculated daily; and for each hour of the
day the hourly Leq, EXCD Leq and
background Leq. Can also show wind or
tachometer data using external
transducers.
Metrics Measurement readings adjusted for night
and day noise impact differences.
Adjustments are based on standard
nighttime sound penalties criteria (i.e.
LDN, CNEL, etc.) The total exceedance
and background Leq metrics are also
displayed.
PassBy Shows the largest single 10 dB passby
event detected with its Leq, SEL, Lmax,
duration, and occurrence date and time.
Wind / Tach Shows wind or tachometer data.

Larson Davis 824 Specifications

General

Brand	Larson Davis
Model	824
Category	Measuring Instruments
Language	English