Kustom Signals Pro-Lite, Справочное руководство

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Pro-Lite Operator’s Manual
Page 12
The greater the angle between the Pro-Lite and the
direction of traffic, the greater the cosine error produced.
For small angles, the cosine effect is relatively insignificant.
For example, at angles of less than 8°, the cosine error is
under 1% , and at angles of less than 14°, the error is
under 3% . As a general guideline, if you select a location
where the distance to the target vehicle is at least ten times
greater than the Pro-Lite's perpendicular distance from the
roadway, this corresponds to an angle of 5.7° or less, and
the amount of cosine error will not exceed ½ % . This is
called the 10:1 rule. For example, setting up 20 feet off
the roadway and measuring targets at a range of 200 feet
or further away, assures the cosine effect produces no
more than ½ % error in the speed measurement. Again, it
is important to remember that any cosine error introduced
always reduces the indicated speed reading, thus favoring
the motorist.
Another factor in selecting a setup location is for
normal
operation: you should have a clear line of sight to
the target vehicle during the entire measurement interval.
Intervening objects such as signposts, utility poles, fences
and tree branches, may prevent the instrument from
gathering sufficient valid measurement data to display a
speed-reading. It is also better to select a setup location
where minimum movement of the Pro-Lite is required in
order to keep it aimed on the desired target.
Visibility conditions may also affect the performance of
the Pro-Lite. Although the laser emissions used by the
device are not in the visible spectrum, they are close
enough in wavelength that atmospheric or climatic
conditions that impair vision may also adversely affect the
unit’s ability to obtain range or speed-readings. This
impact is mitigated to some degree by choosing "Poor" on
the Pro-Lite’s Environment Menu. However, rain, smoke,
fog, and airborne dust particles, if sufficiently dense, may
prevent its operation. The unit’s accuracy is not affected,
just the ability to obtain a speed-reading. The instrument
is not affected by ambient light conditions.