Short Term Exposure Limit (Stel) Mode - PerkinElmer Photovac 2020 Manual

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Short Term Exposure Limit (STEL) Mode

The Short Term Exposure Limit (STEL) mode displays the
concentration as a 15 minute moving average. 2020 maintains 15
samples, each representing a one minute averaging interval.
Once every minute, the oldest of the 15 samples is replaced with a
new one minute average. This moving average provides a 15 minute
average of the last 15 minutes with a one minute update rate. Since
the average is calculated using 15 one minute averages, the meter
display will only update once every minute.
STEL is set to zero each time the instrument is turned on. Since
STEL is a 15 minute moving average, there is no need to clear or
reset the STEL.
STEL calculations are always being performed by 2020. You can
display the results of the calculations by selecting STEL as the
Display mode. See
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