Ambient Air quality Monitoring Guidlines. - Maharashtra Pollution ...

(v) Preparation for Use
(a) Selecting the Site of Operation - In general, anemometers are designed to
record wind conditions over a large area. In order to obtain comparable values
for the determination of surface wind, measurements should be made at a height
of 10 meters over open level terrain. Open level terrain is defined as an area
where the distance between the anemometer and an obstruction amounts to at
least 10 times the height of the obstruction. If, this condition cannot be met, then
the anemometer should be set up at such a height where the measured values
are, to the greatest extent possible, not influenced by local obstructions
(approximately 6-10 meters above the obstruction).
The anemometer should be installed in the middle of flat roofs - not at the edge -
in order to avoid a possible bias to one direction or the other.
(b) Installing the Cup Anemometer - Unscrew the cap nut and remove the deck
plate from the velocity sensor case. Keep the rubber sealing ring in the
protective cap. Install the cup anemometer in such a manner that the dowel pin
(fitting pin) in the crossarms of the cup anemometer screws into the nut in the
protective cap. Replace the deck plate and rescrew the cap nut. While doing
this, hold the sensor by the protective cap not by the cup.
3.1.4 Wind Direction
(i) Installing the Wind Vane - Install the wind vane in the same manner as the
cup. There is no deck plate.
(iii) Installing the Sensor - The sensor can be installed on a pipe of R 1 1/2" (48
mm) and 50 mm length. The internal diameter must amount to at least 36 mm
since the sensor will be plugged into an electrical system at its base. Solder a
flexible control line LiYCY with the required number of leads of 0.74 mm 2 onto
the enclosed plug (see circuit diagram). The line resistance of the leads for the
heater voltage of the sensor should not exceed 1 ohm - if necessary, connect
several parallel leads.
A line resistance up to approximately 10 ohm is admissible for the signal connections.
Following electrical connection, set the sensor on the pipe and make sure that the case markings
face true north. (The bar must also point to the north). Fasten the instrument by means of the
two hexagon cap screws on the shaft. (The electrical connections for the indicators should be
carried out according to the circuit diagrams).
(iii) Maintenance - If, properly installed, the instrument requires no maintenance.
(Severe pollution can lead to blockage of the slots between the rotating and
stable parts of the sensor). Thus, it is recommendable to clean off accumulated
dirt periodically. Certain symptoms of wear and tear can appear on the generator
bearings or on the ball bearings after years of use. One notices this because the
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