CS SR50A, Инструкция по эксплуатации

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SR50A-Series Sonic Ranging Sensors
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FIGURE 9-6. Remove the Two Flat Phillips Screws to Expose the PCB
Carefully reassemble in reverse order.
9.2 Data Interpretation and Filtering
9.2.1 Data Interpretation
Although not common, the SR50A can occasionally output invalid reading
indicators if it was unable to obtain a measurement. For distance to target
values, a 0.0 reading is usually output. For snow depth outputs, the error
indicator value is –999. An invalid temperature reading is also indicated by a
–999 reading. For snow depth applications, these can be easily filtered out
when analyzing the data.
Consideration should be taken in a control type application to deal with invalid
readings. For example, if the sensor is used to initiate a water level alarm,
multiple readings should be used to ensure that a single invalid reading does
not trigger the alarm condition.
9.2.2 Data Filtering
There are scenarios where the SR50A can produce values with higher than
expected errors. For example, in very low density snow, very little echo is
returned back to the sensor. The increase in echo quality numbers is an
indication of the weak signals. Under these circumstances, an SR50A can
under, or over, estimate snow depth. If the signal is too weak, the sensor will
also output a value of 0 for the distance to target. When the echoes are weak,
the sensor also automatically increases sensitivity. This makes the sensor more