ACCUR8 DWS5100 - Relative Pressure Calibration; Wind Gain Calibration

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2. Step by Step Guide
In normal mode, press and hold the SET and ALARM buttons at the same time for five seconds to enter the
barometer, wind speed, rainfall and calibration mode. To skip over a parameter, press (do not hold) the SET
button. The word CAL will appear at the top of the screen.
1. Absolute Pressure Calibration
The absolute pressure offset will begin flashing. The default offset is 0.00 inHg.
Press the [+] or [-] button to increase or decrease the absolute pressure offset.
Press and hold the [+] or [-] button for three seconds to increase or decrease rapidly.
Press the ALARM button to reset current value.
Example: The calibrated pressure source measures 28.00 inHg. The display absolute pressure reads 28.83
inHg on the console.
Offset = 28.00 – 28.83 = 0.83 inHg.
2. Relative Pressure Calibration
Press the SET button and the relative pressure offset will flash. The default is 0.00 inHg
Press the [+] or [-] button to increase or decrease the relative pressure offset.
Press and hold the [+] or [-] button for three seconds to increase or decrease rapidly.
Press the ALARM button to reset current value.
Example: The local official barometer measures 30.00 inHg. The display absolute pressure reads 29.92 inHg
on the console.
Offset = 30.00 – 29.92 = 0.08 inHg.
Note: The display console displays two different pressures: absolute (measured) and relative (corrected
to sea-level).
To compare pressure conditions from one location to another, meteorologists correct pressure to sea-level
conditions. Because the air pressure decreases as you rise in altitude, the sea-level corrected pressure (the
pressure your location would be at if located at sea-level) is generally higher than your measured pressure.
Thus, your absolute pressure may read 28.62 inHg (969 mb) at an altitude of 1000 feet (305 m), but the
relative pressure is 30.00 inHg (1016 mb).
The standard sea-level pressure is 29.92 in Hg (1013.2hpa). This is the average sea-level pressure around
the world. Relative pressure measurements greater than 29.92 inHg (1013.2hpa) are considered high
pressure and relative pressure measurements less than 29.92 inHg are considered low pressure.
To determine the relative pressure for your location, locate an official reporting station near you (the internet is
the best source for real time barometer conditions, such as Weather.com or Wunderground.com), and set
your weather station to match the official reporting station.
3. Wind Gain Calibration
Press the SET button and the wind gain will flash. The default is 1.00.
Press the [+] or [-] button to adjust the wind speed calibration factor from 0.75 to 1.25, where:
Calibrated Wind Speed = Calibration factor x Measured Wind Speed