Larson Davis System 824, Training Manual

Page: 43 / 66

3/22/01 Environmental Measurements 2-11
Below is a graph of a time history for an exceedance:
Hint: Up to ten samples are stored prior to the trigger and up to ten samples
are stored after the exceedance to give a graphical indication of the
noise profile.
Setting the parameters for an
Exceedance History Before setting the parameters for the Exceedance history or
Exceedance time history it is recommended that you get
familiar with the type of events you would like to capture.
Remember that the data recorded in the Exceedance history
are: Duration, Leq, Lmax, SEL, Peak-I, Peak-II, time and
date of occurrence (time at start of event or time of maxi-
mum level)
Referring to the diagrams on the following pages, configure
the 824 with the following parameters:
df
dfdfsasdf
dfdsasdfdsafffffffffffffffffffffffffffffd
T
0
-9 -8 -7 -6 -5 -4 -3 -2 -1
+1+2 +3+4+5+6+7+8+9
Sampling rate from
1/32 of a second to
approx. 8 seconds
10 samples recorded before the event
10 samples recorded after the event
Up to 118 samples