Biral SWS-100-LW: SWS-200-LW, Руководство пользователя

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Sensor Set-up Section 1
16
STEP 5 – Installation
1.5.2 Height Above Ground:
The optimum height at which to mount the sensor depends on the application.
The table below shows recommended heights.
Application Typical height Comment
Highway fog-warning
systems 1.5 to 2 meters
(4.9 to 6.6 feet) Recommended height for the
sensor sample volume is the
average distance of a vehicle
driver's eyes above the
roadway.
Airport applications 4.3 meters (14 feet)
above the runway This is the standard height for
visibility sensors in the U.S.
This height may differ in other
countries.
General meteorological 1.8 meters (6 feet) This is a suitable height unless
the particular application
dictates otherwise.
Table 1-4 Recommended Sensor Height above Ground
1.5.3 Orientation of the SWS – LW Sensor
The orientation of the sensor heads should be such that the rising or setting sun
does not appear in the field-of-view of the receiver lenses.
It is desirable to avoid sunlight from flooding the receiver optics and to avoid
sunlight induced noise spikes from creating false precipitation counts, although
false-alarm algorithms in the sensors invariably eliminate such false counts.
The recommended orientation is shown in the following two diagrams (Figure 1-3
and Figure 1-4).
For the SW-100 – LW sensor, the optimum position is with the receiver head
pointing directly due North.
For the SWS-200 – LW, the optimum position is with the forward scatter receiver
and the back scatter receiver oriented equally either side of due North. This is
with the backscatter head pointing 34˚East of North.