Dynamax Dynamet 5, Руководство пользователя

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Dynamax Inc
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There is an internal solid state instrument contained within the Radiation shield that
provides digital output signals for Relative Humidity, Temperature and calculated Dew
point.

Barometric pressure output is provided by a solid-state device fitted on to a circuit board
inside a MaxiMet molding.

MaxiMet contains a 2-axis compass and magnetic field sensing module using Magneto-
Inductive (MI) sensors. The sensor changes inductance by 100% over its field
measurement range. It incorporates a temperature and noise stabilized oscillator/counter
circuit. The compass has a high degree of azimuth accuracy. MaxiMet uses the internal
compass to electronically sense the difference in the earth's field from the system's
magnetic field, then an on-board microprocessor electronically subtracts out the system's
magnetic fields, reporting highly accurate compass readings. Wind direction data is
corrected for the orientation of the sensor. The output of the wind direction is relative to
magnetic North. The MaxiMet compass is calibrated at Gill Instruments before the unit is
delivered. Prior to installing MaxiMet it is suggested that for best accuracy a declination
figure should be entered. Use of the Compass Corrected Wind direction readings allows
the unit be installed such that accurate positioning of the MaxiMet North Marker is not
required.

Declination is the magnetic declination (the angle between Magnetic North and True
North) in degrees. This is a correction factor that is added to the magnetic north heading
from the compass. Map and declination figures in decimal figures can be obtained from
http://www.ngdc.noaa.gov/geomag/declination.shtml

MaxiMet uses a highly accurate GPS (Optional) antenna receiver module including a
ceramic GPS patch antenna. The module is capable of receiving signals from up to 48
GPS satellites and transferring them into position and timing information that can be read
over a serial port. Small size and high-end GPS functionality are combined with low
power consumption.