Larson Davis 831, User Manual

Page: 126 / 548

Model 831 Manual Run Mode with Measurement History 6-3
The ability to restart when power is
restored following a power failure,
with documentation in the session
log, is a valuable feature for long-
term remote noise monitoring
applications If the unit stops due to a power failure, the session log is
labeled as a type of “Stop” with a cause of “Power”. If,
following a loss of power, the power is restored, the Model
831 will automatically begin running again.
If the unit is paused it will resume automatically after 5
minutes. This prevents loss of data due to an inadvertent
pause, whether done manually or when the preamplifier
cable is removed.
Single Block Timer
Using Single Block Timer, a single measurement is made for
the time interval defined by the single block timer settings.
The measurement may also be started or interrupted
manually by pressing the
9
key or the
7
key. The
Single Block Timer mode is often used to make a
measurement for a period of one week. The setup procedure
is described in ‘Single Block Timer or Daily Timer” on
page 6-8.
Daily Timer
Using Daily Timer, the measurement is initiated for one or
more blocks of time every day within the programmed date
range as set by the Daily Timer settings. The measurement
may also be initiated or interrupted manually pressing the
9
key or the
7
key. The Daily Timer mode is often used
to make a work area survey that follows a worker’s daily
schedule for an entire work week. The setup procedure is
described in ‘Single Block Timer or Daily Timer” on page 6-
8.
Run Mode with Measurement History
This chapter does not address Run
Modes with Measurement History. There are many applications where it is desirable to measure
and store a sequence of measurements using the same setup,
either manually or automatically. With the Model 831 this is
facilitated using the Measurement History feature, which is
described in detail in Chapter 12 "Measurement History" on
page 12-1.