Model 820 Technical Reference Manual
Setting and Viewing Advanced Functions
7-13
Figure 7-2
Passby Diagram
After taking a reading with [Passby] enabled, you may wish to
examine the Passby events. You may also look at this while the
instrument is running. To do this follow this step:
Step 1
Press
L
(Exceedance, which is now Passby), and
using the
u
or
d
keys, scroll through the events.
Use the
l
or
r
keys to look at information
about this event.
a. EXCD-a: Time, PassBy record, and date.
b. EXCD-b: Duration and record number of PassBy
event.
c. EXCD-c: SEL and L
eq
of PassBy event.
d. EXCD-d: Max RMS level and Symmetry of
PassBy record.
e. EXCD-e: Peak PassBy level and UWPK of
PassBy record.
If “PSBY” appears in the screen it
means you are in the Max PassBy
data screen. Hit
U l
to get
into the Exceedance PassBy
screen.
Five screens are available here by
using the
r
key, giving time and
date of the occurrence, duration,
and L
eq
comparisons.
Symmetry when used in PassBy
mode is an indication of where
Occurrence Time (or Max Level)
occurs in the event. To clarify, 25%
symmetry would indicate Max
Level happened 1/4 of the way into
the event in linear time. 50%
would suggest that the Occur-
rence Time happened half way into
the event, and so forth.
_________________________
Occurrence
___________________________________
______Duration__________
Start of
Exceedance
Passby’s Max
Time
10dB
