Using the LI-8150 Multiplexer
10-81
Observation Length
The Observation Length is the time period from the instant the chamber is closed
until just before it begins to open again, and includes the specified Dead Band
period. At low to moderate CO
2
fluxes an Observation Length of 90 to 120
seconds is usually adequate.
Note that the LI-8100A starts logging data when the chamber is actuated and starts
to close. Raw, or Type 1 records are recorded throughout the entire observation
period. The Elapsed Time (labeled etime on the data output) does not increment,
however, until the chamber is closed. While the chamber is closing, etime is set to
-1 for all records collected.
Enable 'End Observation at' and enter a relative humidity value, if desired. The
observation will abort if the measured relative humidity in the chamber exceeds
this value at any time during the measurement. If the observation is aborted, a
message is placed in the log file, and the measurement will continue at the next
observation.
Dead Band
The Dead Band is the time period that starts when the chamber closes and
continues until steady mixing is established and the measurement begins. The
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