Davis Instruments Vantage Pro2 manual Barometric Pressure

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You can also use dew point to predict the minimum overnight temperature. Provided no new fronts are expected overnight and the afternoon Relative Humidity is greater than or equal to 50%, the afternoon’s dew point gives you an idea of what minimum temperature to expect overnight, since the air can never get colder than the dew point.

Rain

Vantage Pro2 incorporates a tipping-bucket rain collector in the ISS that measures 0.01'' for each tip of the bucket. A metric adapter can be installed to measure 0.2 mm for each tip of the bucket.Your station logs rain data in the same units it is measured in and converts the logged totals into the selected display units (inches or millimeters) at the time it is displayed. Converting at display time reduces possible compounded rounding errors over time.

Four separate variables track rain totals: “rain storm”, “daily rain”, “monthly rain”, and “yearly rain”. Rain rate calculations are based on the interval of time between each bucket tip, which is each 0.01'' rainfall incre- ment or .2 mm.

Barometric Pressure

The weight of the air that makes up our atmosphere exerts a pressure on the surface of the earth. This pressure is known as atmospheric pressure. Generally, the more air above an area, the higher the atmospheric pressure, this, in turn, means that atmospheric pressure changes with altitude. For example, atmospheric pressure is greater at sea-level than on a mountain- top. To compensate for this difference and facilitate comparison between locations with different altitudes, atmospheric pressure is generally adjusted to the equivalent sea-level pressure. This adjusted pressure is known as barometric pressure. In reality, the Vantage Pro2 measures atmo- spheric pressure. When you enter your location’s altitude in Setup Mode, the Vantage Pro2 stores the necessary offset value to consistently translate atmospheric pressure into barometric pressure.

Barometric pressure also changes with local weather conditions, making barometric pressure an extremely important and useful weather forecasting tool. High pressure zones are generally associated with fair weather while low pressure zones are generally associated with poor weather. For fore- casting purposes, however, the absolute barometric pressure value is gen- erally less important than the change in barometric pressure. In general, rising pressure indicates improving weather conditions while falling pres- sure indicates deteriorating weather conditions.

Solar Radiation

What we call “current solar radiation” is technically known as Global Solar Radiation, a measure of the intensity of the sun’s radiation reaching a horizontal surface. This irradiance includes both the direct component

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Contents Vantage Pro2 Console Manual Vantage Pro2 Console Display Features Vantage Pro 2 Console ManualTable of Contents Console Features Chapter Welcome to Vantage Pro2Keyboard & Display Printed on that keyVantage Pro Options Console ModesOptional Sensors Optional WeatherLink SoftwareOptional Accessories Chapter Installing the Console Powering the ConsoleInstalling the AC Power Adapter Ies provide backup power for up to four to six weeksInstalling Batteries Connecting Cabled StationsInstallation Manual Console LocationTested and established Cabled consoleTable & Shelf Placement Wall Mounting Chapter Using Your Weather Station Setup ModeSetup Mode Commands Screen 1 Active Transmitters Screen 1 Active TransmittersScreen 2 Configuring Transmitter IDs Wireless Only Screen 3 Retransmit Wireless OnlyScreen Screen 4 Time & Date Screen 5 Latitude Screen 6 Longitude Screen 7 Time ZoneScreen 8 Daylight Savings Settings Screen 9 Daylight Savings Status Screen 10 ElevationScreen 11 Wind Cup Size Screen 12 Rain Collector Data logger installed on the console Press and release 2ND and press Units onceScreen 13 Rain Season Screen 14 Serial Baud RateCurrent Weather Mode Clear All CommandSelecting Units of Measure Selecting Weather VariablesSelected variable’s units will change. Repeat Press Wind to select wind speedPress 2ND then press Chill to select Wind Chill Wind Chill is displayed in either Fahrenheit ºF or CenPress 2ND then press Heat to display the Heat Index Press Rainday to display the rain accumulated since 12 mid Night. Any rain accumulated in the last 24 hours displaysTicker at the bottom of the screen Press 2ND then press Lamps to turn on the backlight for Screen display. Press 2ND then Lamps again to turn the backCalibrating, Setting, and Clearing Variables Calibrating Temperature And HumidityDisplaying the Forecast Displaying Time & Date or Sunrise & SunsetAfter a moment, the variable you’ve selected begins Calibrate Wind Direction ReadingReading Setting Weather Variables Calibrating Barometric PressureClearing Weather Variables Highs and Lows Mode Viewing Highs and Lows Alarm Mode Four Special AlarmsSetting Alarms Setting the Time AlarmClearing Alarm Settings Graph Mode Silencing AlarmsPress Done to silence an alarm when it sounds Viewing Graphs Weather Variable Available Graphs Chapter Troubleshooting and Maintenance Vantage Pro2 Troubleshooting GuideProblem Solution Rain Console Diagnostic Screens Accessible to a cabled weather stationNumber of packets containing errors that were received Number of missed data packetsReception Diagnostic Screen Console Maintenance One Year Limited WarrantyAppendix a Weather Data 30% even though water vapor content does not change SorTive humidity Ity has a large capacity to absorb extra water vaporBarometric Pressure Pro2 displays UV readings in two scales MEDs and UV Index MED for persons with very light skinSkin Phototype Skin color Tanning & Sunburn history Skin Type Skin Color History of Tanning & Sunburning IIIIndex Values Exposure Category Appendix B Specifications Wireless Communication SpecificationsConsole Console Data Display Specifications Weather Data Specifications Variable Required SensorsThsw Vantage Pro2 Console Icons Forecast