METER ATMOS 41, Руководство пользователя

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3.7 LIGHTNING SENSOR
The lightning sensor acts much like an AM radio. During a thunderstorm, the crack of the
lightning disrupts the AM signal. The integrated circuit inside the sensor listens for this
crackle, and when the sensor detects a disturbance, it registers the time of and distance
(intensity of signal) to the strike. The sensor outputs the total number of strikes and average
distance to these strikes in the measurement period. The sensitivity of the lightning sensor
can be adjusted using the ProCheck (see
Section 3.9 on page 18 ).
3.8 COMPASS
The ATMOS 41 has an internal digital compass that is used primarily as a diagnostic tool to
determine if the ATMOS 41 has been inadvertently rotated after installation. It can also be
used to correct the wind direction measurement, but only if the ATMOS 41 is mounted on a
nonferrous mounting pole, as ferrous metal interferes with the digital compass accuracy.
All ATMOS 41 units are shipped with the compass-corrected wind direction turned OFF, so
the typical installation requires that the
N on the side of the weather station be oriented to
north (true north, not magnetic north) for accurate wind direction measurements.
If the ATMOS 41 is mounted on a nonferrous pole, the wind direction compass correction can
be turned
ON (see
Section 3.9 on page 18 ) and the ATMOS 41 does not need to be oriented
towards north for accurate wind direction measurements.
NOTE: The compass-corrected wind direction will orient to magnetic north, so a correction will have to be applied to
account for magnetic declination.
Even if the compass correction is turned OFF, the compass orientation will still be
included in ATMOS 41 output, even if a ferrous metal post is affecting the accuracy of
the measurement. These orientation data are still useful as a diagnostic tool to identify
unintended rotation of the ATMOS 41, which would affect the accuracy of the wind
direction measurement.