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position of the vane. By orienting the vane to North (360 degrees) during installation,
wind can be easily calculated from the output voltage. The resolution of the wind vane
is 1 degree (azimuth display), or 16 compass points (cardinal points display).
1.5.2 Barometric Pressure
Barometric pressure is sensed using a piezoresistive sensing element. This element
responds to changes in barometric pressure with a corresponding change in resistance.
This resistance is converted to a voltage from which the microprocessor calculates the
barometric pressure at the elevation where the sensor is located.
The barometric pressure sensor is set for sea level when it leaves the factory. Because
pressure varies with elevation, the sensor must be adjusted to read correctly for the
elevation at which it is installed. This is done using the offset adjustment screw located
on the side of the sensor. Instructions are provided in the installation section of this
manual. (See page 10.)
1.5.3 Temperature and Relative Humidity
The WS-16-A is designed to accommodate a combination temperature and relative
humidity sensor. Temperature is sensed using a thermistor element which changes
resistance in response to temperature fluctuations. Relative humidity is sensed by
changes in the dielectric constant of a thin polymer film as it absorbs moisture or sheds
it to the surrounding air.
For maximum accuracy, the sensor should be isolated from the effects of sunlight which
can cause misleading temperature and humidity measurements. The WS-16-A-THS
self-aspirated solar radiation shield is provided to give this protection.
1.5.4 Rain
The rain gauge provided with the WS-16-A is a traditional tipping bucket design.
Resolution is 0.01 inches (0.254 mm) per tip.
1.6 Using the Data
Once the weather data generated by the WS-16-A has been logged and saved, either
within the data acquisition module or on external media, it can easily be manipulated by
a number of commercially available software packages. The format of the columnar,
coma-delimited data was carefully designed to make it compatible with most widely
used spreadsheet programs. The data can be imported easily into these programs and
then analyzed or manipulated, making the information generated by the WS-16-A much
more than simply a collection of numbers.
2.0 INSTALLATION
Installation of the WS-16-A is simple and straightforward, thanks to its modular design
and terminal-strip connections.
Содержание 110-WS-16
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