1
MODEL 200-WS-03D
WIND & TEMPERATURE SENSOR
1.0
INTRODUCTION
This manual contains information to aid in the design of custom interface circuits for use
with the NovaLynx Model 200-WS-03D combination Wind and Temperature Sensor. This
information is supplied to systems integrators with the express understanding that
NovaLynx Corporation assumes no responsibility or liability for the operation of the sensor
as a part of any equipment that has been designed or furnished by any organization other
than NovaLynx.
The Model 200-WS-03D Wind and Temperature Sensor assembly consists of three major
parts: an anemometer for measuring wind speed; a wind vane for measuring horizontal
wind direction; a thermistor temperature sensor. The complete sensor assembly has been
designed with the wind vane mounted on top of the anemometer for stability and ease of
signal transmission. A small white shield protects the thermistor from direct solar heating
and is located on the side of the sensor where the thermistor passes through the sensor
housing. Output signal transmission is accomplished through a forty-foot length of six-
conductor, twenty-six gauge, flat cable. The cable has been terminated by a six-pin RJ-11
connector. Monitoring equipment supplied by NovaLynx will be equipped with a matching
connector receptacle.
1.1
ANEMOMETER
The anemometer uses a three-cup hub and cup assembly to sense wind velocity. As the
wind blows past the cups, the pressure of the wind against the insides of the cups causes
them to rotate. There are three permanent magnets embedded in the hub that holds the
cups. Each magnet, as it rotates past a fixed point on the sensor base, activates a
magnetic reed switch mounted in the base. Three closures of the reed switch will be
produced for each revolution of the cup assembly. The contacts of the magnetic reed
switch capsule are normally open; the contact will close each time a magnet passes over
it. The ratio of closed-to-open time is nominally 1/10 of the total period for a revolution of
the wind cups. This duty cycle may change slightly as the sensor ages and with exposure
to temperature extremes.
The anemometer is rated for wind speeds up to 125 miles per hour and has a starting
threshold of approximately 1 mile per hour. The magnetic reed switch capsule is rated to
carry a maximum current of 10.0 milliamperes with an applied voltage of no more than 50
volts AC or DC. The approximate speed constant for the anemometer is 1.25 mph/Hz.
