Figure 7 Recommended Location Of Pwd22/52 Sensor - Vaisala PWD22/52 User Manual

USER'S GUIDE____________________________________________________________________
30 __________________________________________________________________ M210543EN-E
Figure 7
A = Sensor mounted on a supporting arm.
B = Sensor mounted on top of a mast.
- The receiver and transmitter optics should not point towards
powerful light sources. It is recommended that the receiver will
point north in the northern hemisphere, and south in the southern
hemisphere. The receiver circuit may become saturated in bright
light, in which case the built-in diagnostics will indicate a
warning. Bright daylight will also increase the noise level in the
receiver.
- The transmitter and receiver should face away from any obvious
source of contamination such as spray from passing vehicles.
Dirty lenses will cause the sensor to report too high visibility
values. Excessive contamination is automatically detected by the
sensor.
- In the road environment the receiver should face away from
passing vehicles. The preferred orientation is along the road. A
receiver pointing towards driving direction of the closest lane.
The possible reflections from the passing cars might generate
false snow detections in the winter time.
3. Power supply and communication lines must be available.
- When siting PWD22/52, consideration must be given to the
available power supply and communication lines, as this
influences the amount of work and accessories needed, and
hence the actual cost of installation.
Although PWD22/52 is designed to withstand harsh weather conditions,
there are locations where the environment places further demands for
installation. For harsh wintry conditions, optional hood heaters are
available to prevent ice and snow accumulation.
Recommended Location of PWD22/52 Sensor.
0308-003