Record Sample Data for Alarm Design
In order to design effective alarms for acoustically triggered curtailment (ATC) on a particular turbine, you should collect sample recordings from that same turbine. The characteristics of the turbine machinery, local weather, and where microphones are placed on the turbine will affect what kinds of noise your microphones records.
Before you begin
The SMART System's alarms will only process sounds that satisfy the pulse-level trigger parameters defined in a Setting Profile, including minimum and maximum frequency and duration criteria. When recording sample data, you may wish to set these criteria to be broader than normal to ensure that all possible bat activity is recorded and accounted for.
About this task
There is no universally effective set of alarms for ATC. Effective alarms detect nearby bat activity while preventing false triggers from the noise of the turbine. On each turbine, you will record noise with different characteristics and will need to employ different strategies to separate the mechanical noise from bat vocalizations. Therefore, collecting sample data from each turbine is key to designing effective alarms for ATC on that turbine.
Procedure
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Record sample data using the same microphone placements you will use during
ATC.
Changing the placement of a microphone may change the characteristics of the mechanical noise you record.Changing the placement of a microphone can also increase or decrease the presence of reflections of bat vocalizations off of hard surfaces. These reflections can change the apparent duration of nearby bat activity.
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Record sample data in a variety of weather conditions to capture different
turbine behaviors.
The characteristics of a turbine's mechanical noise may vary with wind speed.
- Record across a long-enough timespan to capture seasonal variations in bat behavior.
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Record both WAV and ZC files.
Actual alarm behavior is based on the SMART System's ZC output, so ZC files should be used when testing alarm behavior in Kaleidoscope Pro. WAV files display fuller information about the audio being captured, so they are useful when manually examining files during testing.