User Manual

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8.4.2 Sampling Rate
8.4.2.1 SLM Instantaneous Rate
The SLM Instantaneous Rate spans from 10 ms to 1 s. This parameter defines the rate at which the
SLM data are managed in the application in general. This impacts the sampling of the SLM historic
graph as well as the record rate of SLM data in Instantaneous Record Mode.
Some sampling rates may not be suitable for some measure types. If such a combination occurs, a
warning is displayed but does not prevent the user from proceeding with measurement. For
example, a sampling rate of 1 s is not suitable to correctly reproduce the Fast SPL as it is subject to
vary more rapidly in time.
The FFT rate is set automatically from 256 ms, 512 ms or 1024 ms according to the selected Sampling
Rate.
8.4.2.2 Leq Average Time
The Leq Average Time can be set between 1 s to 24 hrs. Simply click on the field to modify this value.
This value can also be modified on the Leq Averaging Time indicator on the main interface.
The Leq Average Time defined the average period for the evaluation of Leq data. The same period is
used to evaluate the minimum, the maximum and the statistics. This average time also drive the rate
that the data are saved in Average Record Mode.
8.4.3 Data Selection Options
The Data Selection Presets automatically selects the data to be recorded. The table below
summarizes these options, as well as their advantages and drawbacks.