Observator OMC-160-3, Manual

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OMC-160-3
Manual Page 7
3 Description
3.1 General description
The Observator OMC-160-3 is a combined wind speed and direction meter using high accurate non-
contact sensors. It uses a rotary cup with 3 cups for speed and a stainless steel balanced vane for
direction measurement. It has a NMEA output signal and be combined with all Observator display and
MeteoL
l ink systems.
3.2 Main parts
The OMC-160 anemometer consists of a sensor body and a mounting bracket. Note that the mounting
bracket, though it was sometimes referred to as OMC-167, is an integral part of the OMC-160
anemometer. The mounting bracket has a mast clamp for mechanical connection and a junction box for
electrical connection. This clamp is designed for mounting on a vertical pipe end.
3.3 Moving parts
The only moving parts are the cup unit and the vane unit. The vane unit is mounted on top of the sensor
body, and the cup unit is mounted at the bottom of the sensor body. Both the cup unit and the vane unit
are wind driven. The wind speed sensor is a rotary cup type unit manufactured in stainless steel and
polycarbonate. The three cups are cone shaped for optimum response to varying winds. The vane unit is
made in stainless steel.
3.4 Theory of Operation
The OMC-160 is a cup and vane anemometer. Cup and vane anemometers are the most common
instrumentation for measurement of wind speed and direction. Cup and vane anemometers are the
primary sensors for wind measurement used by the leading meteorological services all over the world.
Therefore the readings of the OMC-160 anemometer are inter-comparable with the readings of other cup
and vane anemometers without any conversions.
For a more comprehensive discussion on the measurement principle please refer to Chapter 5 of the
WMO CIMO guide
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3.5 Conditions of use.
The OMC-160 anemometer is built to provide reliable measurement results under all weather conditions.
Rain, snow, or other kinds of precipitation do not affect the readings. Further, the OMC-160 anemometer
is insensitive to noise, extreme temperatures, solar radiation, etc.
1
Guide to Meteorological Instruments and Methods of Observation, WMO No. 8, 7th Edition, World Meteorological
Organisation, Geneva, Switzerland, ISBN 92-63-16008-2