CS SR50A, Инструкция по эксплуатации

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SR50A-Series Sonic Ranging Sensors
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prone to the occasional erroneous reading from flying debris, drifting snow, or
mounting hardware just outside the beam angle.
The reason not to average values is that occasionally a number with a very high
error value is produced, skewing the average. The value should be ignored and
not averaged. Based on experience, the best technique to eliminate errors and
filter out high error readings is to take the median value. This technique also
helps to automatically filter out zero readings that can occasionally be
produced.
For example, for a given station, a reading is taken every 5 seconds for 1
minute and the median value is taken from the readings. All the programming
examples in this manual use this method for data filtering.
If 11 consecutive values are as
follows for snow depth
After being sorted from
low to high
0.33 –1.1
0.34 0.10
0.35 0.28
–1.1 (erroneous reading) 0.32
2.0 (erroneous reading) 0.33
0.37 0.33
0.28 0.34
0.36 0.35
0.10 (high error value) 0.36
0.33 0.37
0.32 2.0
The best course of action would be to ignore the 5 lowest values and take the
6th value (0.33).