Larson Davis System 824 Training Manual page 4

824 Training Manual
Printing a Report .........................................................................................1-23
Exporting Data ............................................................................................1-23
Content of Reports ......................................................................................1-23
Chapter 2 Environmental Measurements
Environmental Noise ..............................................................................................2-1
Types of Environmental Noise ..........................................................................2-1
Why Measure Community Noise? .....................................................................2-3
824 LOG Instrument ...............................................................................................2-4
What Does the LOG Instrument Measure?........................................................2-4
Time History ......................................................................................................2-4
Interval History ..................................................................................................2-6
Exceedance History............................................................................................2-8
Exceedance Time History ...........................................................................2-10
Setting the parameters for an Exceedance History......................................2-11
Viewing Exceedance History Data on the 824............................................2-14
PassBy Exceedance .....................................................................................2-15
PassBy Measurement ..................................................................................2-16
Daily History....................................................................................................2-16
Explanation of Ldn and CNEL....................................................................2-17
Hourly Statistics ..........................................................................................2-17
Metrics .............................................................................................................2-18
iv
Summary Report.......................................................................... 1 -23
Time History Report....................................................................1-25
Interval Report.............................................................................1-26
***Special advanced feature.....................................................................2-7
Time synchronization........................................................ 2-7
Excd Enable (Yes) .............................. ...............................2-12
Min Duration (000)........................................................... 2-12
Excd Time-Hist (Yes) ........................... . ............................2-12
T.H. Period (032)............................... . ................................2-12
Excd Trigger (Level) ........................... . .............................2-12
Excd Time (Start)............................... ................................ 2-12
Excd-a...................................................................................2-14
Excd-b .......................................... ........................................2-14
Time History .................................... ...................................2-15
Hourly Leq...................................... ................................... 2-18
Background Leq ................................. . ..............................2-18
Hourly Excd Leq ................................ ................................2-18
DNL (Ldn) ..........................................................................2-19