Larson Davis 831 - Event History; Level Based Events

Model 831 Manual Event History 13-1
CHAPTER
13
Event History
The optional firmware module 831-ELA is required in
order to measure and store the metrics associated with
exceedance events.
Level Based Events
Read “Triggers Tab” on page 4-11
prior to working with the Event
History module.
Event History provides enhanced information on measured
events defined by the user. Events are initiated and stored
when the measured sound level exceeds the trigger levels
SPL1 and Peak 1 for the specified minimum duration.
SPL1 and Peak 1 are specified on the Triggers tab and the
minimum duration is specified on the Event History tab.
Basic Measurement Data
When the basic measurement capability of the Model 831 is
utilized, as described in the section “Triggering” on page 5-
7, only a very limited set of data are saved for each threshold
associated with the five trigger levels:
• The number of exceedances for each threshold level.
• The sum total of the time the measured level was above
each threshold.
Event History Data
Event History provides a detailed record for each noise
event including metrics such as:
• Date and time
• Duration
• Equivalent level (Leq)
• Maximum RMS and Peak levels
• 1/1 or 1/3 Octave Leq and max spectra (optional 831-
OB3 firmware required)