MeteoHeerhugowaard

Meteoheerhugowaard maakt gebruik van een Davis Vantage Pro 2 Weerstation. 6152c

Het Davis Vantage Pro 2 weerstation is opebouwd uit een Integrated Sensor Suite, een anemometer (windmeter) met windvaan en een console:

De Integrated Sensor Suite bevat een regenmeter (zwarte beker), een temperatuurs- en luchtvochtigheidssensor, Een sensor unit verstuurd alle weerdata naar de console.
De temperatuurs- en luchtvochtigheidsmeting hangt op precies 1,5 m hoogte boven het aardoppervak in een witte sensorhut, zoals voorgeschreven door de WMO.

De hoeveelheid neerslag wordt door de regenmeter automatisch gemeten. Onder de trechter van de regenmeter bevindt zich een kantelmechanisme. Telkens één van de twee schepjes is volgelopen kantelt het systeem en loopt het schepje leeg. Het andere schepje komt dan onder de trechter terecht

Telkens wanneer de schepjes kantelen, beweegt een magneetje onderaan de schepjes over een detectie-eenheid en wordt via de transmitter een signaal verstuurd. Er is 0.2 mm neerslag gevallen.

De windsnelheid en windrichting worden gemeten door middel van een anemometer met windvaan. Deze bevindt zich op het dak op een hoogte van ongeveer 10 meter. De anemometer is weer aangesloten op de Integrated Sensor Suite (ISS) die er op zijn beurt weer voor zorgt dat de data naar de console gaat.

In de console zitten ook nog 3 sensoren namelijk Luchtdruk , binnen tempratuur en binnen luchtvochtigheid .
Alle sensoren komen binnen op de console en worden daar verwerkt.

De console bevat tevens een datalogger. Alle gegevens, die gegenereerd worden door de console, worden hier in opgeslagen.
De console is zo ingesteld dat dit gebeurt om de 5 minuten.
Indien de data logger niet uitgelezen kan worden is het mogelijk tot 6 maanden weerdata te bewaren.

Via een RS232 verbingen is de datalogger aangeloten op een Linksys NSLU2 .
Deze is voorzien van een nieuwe Firmware (SLUG Firmware) waardoor het een klein zelfstandige Linux computer is geworden.
De NSLU2 draaid op een 266 MHz cpu met 32 Mb werkgeheugen, verder is er een externe 2,5" harddisk op aangesloten waarop Wview software geinstaleerd is.
Het grote voordeel van deze oplossing is dat het erg energie zuinig is (<6W), stil en geen warmte ontwikkeling, ideaal dus voor 24X7X365 gebruik.

De weerdata worden door specifieke software (Wview) verwerkt tot tabellen, grafieken, weerbulletins enz...
Wview zorgt er tevens voor dat alle actuele gegevens in een template terecht komen. Deze templates met grafieken en tabellen worden om de minuut ververst en online gezet op de website van MeteoHeerhugowaard.
Om er voor te zorgen dat de juiste tijd bij de data word opgeslagen is er ieder uur een tijd synchronisatie.

Hieronder nog een Hardware en Software schema van de opbouw van dit meteo station:

Hieronder nog de uitgebreide specificatie van de Davis Vantage Pro 2:

Vantage Pro2

The Vantage Pro2 (# 6152C) and Vantage Pro2 Plus (# 6162C) cabled weather stations include two components:
the Integrated Sensor Suite (ISS) and the console. The ISS contains the sensor interface module (SIM), rain collector,
an anemometer, and a passive radiation shield. The Vantage Pro2 console provides the user interface, data display,
and calculations. The Vantage Pro2 Plus weather station includes two additional sensors that are optional on the
Vantage Pro2 and purchased separately: the UV Sensor and the Solar Radiation Sensor. The console and ISS are
powered by an AC-power adapter connected to the console. Batteries can be installed in the console to provide a
backup power supply. Use WeatherLink for Vantage Pro and Vantage Pro2 to let your weather station interface with
a computer, log data, and upload weather information to the Internet. The 6152C and 6162C models rely on passive
shielding to reduce solar-radiation induced temperature errors in the outside temperature sensor readings.
Integrated Sensor Suite (ISS)
Operating Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . -40° to +140°F (-40° to +60°C)
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . -50° to +158°F (-45° to +70°C)
Power Source, ISS SIM. . . . . . . . . . . . . . . . . . . . . . . . . . Vantage Pro2 console / AC-power adapter
Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Modular RJ-11
Cable Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-conductor, 26 AWG
Cable Length, Console . . . . . . . . . . . . . . . . . . . . . . . . . . 100' (30 m) (supplied) 1000' (300 m) (maximum recommended)
Cable Length, Anemometer . . . . . . . . . . . . . . . . . . . . . . . 40' (12 m) (supplied), 240' (73 m) (maximum recommended)
Wind Speed Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . Large wind cups with magnetic switch
Wind Direction Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . Wind vane with potentiometer
Rain Collector Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tip bucket, 0.01" per tip, 33.2 in (214 cm ) collection area
Temperature Sensor Type. . . . . . . . . . . . . . . . . . . . . . . . Thermistor
Relative Humidity Sensor Type . . . . . . . . . . . . . . . . . . . . Film capacitor element
Housing Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UV-resistant PVC plastic
Sensor Inputs
RF Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RC low-pass filter on each signal line
ISS Dimensions:
Product # Dimensions (Length x Width x Height) Package Weight
6152C 5.7 lbs. (2.6 kg)
11.0" x 9.3" x 14.0"
(279 mm x 238 mm x 355 mm)
6162C 6.1 lbs. (2.8 kg)
Console Operating Temperature . . . . . . . . . . . . . . . . . . . +14° to +140°F (-10° to +60°C)
Display Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . +32° to +140°F (0° to +60°C)
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . -5° to +158°F (-20° to +70°C)
Current Draw (includes ISS) . . . . . . . . . . . . . . . . . . . . . . 0.10 mA (average), 15 mA (peak) (plus 120 mA for illuminated display)
at 4 to 6 VDC
Power Adapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 VDC, 200 mA
Battery Backup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 C-cells
Battery Life (no AC power) . . . . . . . . . . . . . . . . . . . . . . . 1 month (approximately)
Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Modular RJ-11
Housing Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UV-resistant PVC plastic
Console Display Type . . . . . . . . . . . . . . . . . . . . . . . . . . . LCD Transflective
Dimensions (Console: length x width x height; Display: length x height)
Console . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.63" x 1.50" 6.13" (244 mm x 38 mm x 156 mm)
Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.94" x 3.375" (151 mm x 86 mm)
Weight (with batteries) . . . . . . . . . . . . . . . . . . . . . . . . . . 1.88 lbs. (.85 kg)

Data Displayed on Console

The data display categories represent all weather variables that the console displays and are listed in alphabetical
order. General describes the general ways in which data is displayed and archived for all data display categories and
is listed first as a point of reference. See the individual data display categories for specific display information.
General
Daily Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Includes the earliest time of occurrence of highs and lows; period
begins/ends at 12:00 am
Monthly Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Period begins/ends at 12:00 am on the first of the month
Yearly Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Period begins/ends at 12:00 am on the first of January unless
otherwise noted
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . .Current display data describes the current reading for each weather
variable. In most cases, the variable lists the most recently updated
reading or calculation. Some current variable displays can be
adjusted so there is an offset for the reading.
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Current graph data appears in the right most column in the console
graph and represents the latest value within the last period on the
graph; totals can be set or reset. Display intervals vary. Example
include: Instant, 15-min., and Hourly Reading; Daily, Monthly, High
and Low
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . Includes the past 24 values listed unless otherwise noted; all can be
cleared and all totals reset. Display intervals vary. Examples include:
15-min., and Hourly Reading; Daily, Monthly, High and Low
Graph Time Interval Length . . . . . . . . . . . . . . . . . . . . . . . 1 min., 10 min., 15 min., 1 hour, 1 day, 1 month, 1 year (user-
selectable, availability depends upon variable selected)
Graph Time Span. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Intervals + current interval (see graph intervals to determine time
span)
Graph Variable Span (Vertical Scale) . . . . . . . . . . . . . . . .Automatic (varies depending upon data range); Maximum and
Minimum value in range appear in ticker
Alarm Indication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Alarms sound for only 2 minutes (time alarm is always 1 minute) if
operating on battery power. Alarm message is displayed in ticker as
long as threshold is met or exceeded. Alarms can be silenced (but not
cleared) by pressing the DONE key.
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Varies with sensor - see individual sensor specifications

Barometric Pressure

Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . .Measured in 0.01" Hg. Other units are converted from Hg and
rounded to nearest 0.1 mm, 0.1 hPa, 0.1mb
Corrected Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26.00" to 32.00" Hg, 660.0 to 810.0 mm Hg, 880.0 to 1080.0 hPa/mb
Uncorrected Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16.00" to 33.50" Hg, 406.0 to 850.0 mm Hg, 542.0 to 1130.0 hPa/mb
Elevation Range. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1500' to +15,300' (-460 m to 4670 m). The console screen limits
display of lower elevation to -999' when using feet as elevation unit.
Uncorrected Reading Accuracy . . . . . . . . . . . . . . . . . . . . ±0.03" Hg (±0.8 mm Hg, ±1.0 hPa/mb) (at room temperature)
Sea-Level Reduction Equation Used . . . . . . . . . . . . . . . .United States Method employed prior to use of current "R Factor"
method
Equation Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Smithsonian Meteorological Tables
Equation Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.01" Hg (±0.3 mm Hg, ±0.3 hPa/mb)
Elevation Accuracy Required . . . . . . . . . . . . . . . . . . . . . . ±10' (3m) to meet equation accuracy specification
Overall Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.04" Hg (±1.0 mm Hg, ±1.4 hPa/mb)
Trend (change in 3 hours) . . . . . . . . . . . . . . . . . . . . . . . .Change 0.06" (2.0 hPa/mb, 1.5 mm Hg) = Rapidly
Change 0.02" (0.7hPa/mb, 0.5 mm Hg)= Slowly
Trend Indication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 position arrow: Rising (rapidly or slowly), Steady, or Falling (rapidly
or slowly)
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 minutes or when console BAR key is pressed twice
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant, 15-min., and Hourly Reading; Daily, Monthly, High and Low
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-min. and Hourly Reading; Daily, Monthly Highs and Lows

Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High Threshold from Current Trend for Storm Clearing (Rising Trend)
Low Threshold from Current Trend for Storm Warning (Falling Trend)
Rising and Falling Trend Alarms Range. . . . . . . . . . . . . . 0.01 to 0.25" Hg (0.1 to 6.4 mm Hg, 0.1 to 8.5 hPa/mb)

Clock
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±8 seconds/month
Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 minute
Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Time: 12 or 24 hour format (user-selectable)
Date: US or International format (user-selectable)
Adjustments
Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic Daylight Savings Time (for users in North America, Europe
and Australia that observe it in AUTO mode, MANUAL setting available
for all other areas)
Date. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic Leap Year
Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Once per day at set time when active

Dewpoint (calculated)
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1°For 1°C. Celsius is converted from Fahrenheit and rounded to the
nearest 1°C
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -105° to +130°F (-76° to +54°C)
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±3°F (±1.5°C) (typical)
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 seconds
Source. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . World Meteorological Organization (WMO)
Equation Used. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . WMO Equation with respect to saturation of moist air over water
Variables Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Outside Temperature and Instant Outside Relative Humidity
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Calculation
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Calculation; Daily, Monthly High and Low
Historical Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . Hourly Calculations; Daily, Monthly Highs and Lows
Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High and Low Threshold from Instant Calculation

Evapotranspiration (calculated, requires Solar Radiation Sensor)
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . Measured in 0.01". Converted to mm and rounded to nearest 0.2 mm
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Daily to 99.99" (999.9 mm); Monthly & Yearly to 199.99" (1999.9 mm)
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Greater of 0.01" (0.25 mm) or ±5%, Reference: side-by-side
comparison against a CIMIS ET weather station
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 hour
Calculation and Source . . . . . . . . . . . . . . . . . . . . . . . . . . Penman-Monteith Equation as implemented by CIMIS (California
Irrigation Management Information System) including Net Radiation
calculation
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . Latest Hourly Total Calculation
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Latest Hourly Total Calculation, Daily, Monthly, Yearly Total
Historical Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . Hourly, Daily, Monthly, Yearly Totals
Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High Threshold from Latest Daily Total Calculation

Forecast
Variables Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Barometric Reading & Trend, Wind Speed & Direction, Rainfall,
Temperature, Humidity, Latitude & Longitude, Time of Year
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 hour
Display Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Icons on top center of display; detailed message in ticker at bottom
Variables Predicted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sky Condition, Precipitation, Temperature Changes, Wind Direction
and Speed

Heat Index (calculated)
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1°F or 1°C. Celsius is converted from Fahrenheit and rounded to the
nearest 1°C
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40° to +135°F (-40° to +57°C)
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±3°F (±1.5°C) (typical)
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 seconds
Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .United States National Weather Service (NWS)/NOAA
Formulation Used. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Steadman (1979) modified by US NWS/NOAA and Davis Instruments
to increase range of use
Variables Used. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Outside Temperature and Instant Outside Relative Humidity
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Calculation
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Calculation; Daily, Monthly High
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . . . . .Hourly Calculations; Daily, Monthly Highs
Alarm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .High Threshold from Instant Calculation

Humidity
Inside Relative Humidity (sensor located in console)
Resolution and Units. . . . . . . . . . . . . . . . . . . . . . . . . 1%
Range. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 100% RH
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±5%
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 minute
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . Instant (user-adjustable offset available)
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . Instant, Hourly Reading; Daily, Monthly High and Low
Historical Graph Data . . . . . . . . . . . . . . . . . . . . . . . .Hourly Readings; Daily, Monthly Highs and Lows
Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .High and Low Threshold from Instant Reading
Outside Relative Humidity (sensor located in ISS)
Resolution and Units. . . . . . . . . . . . . . . . . . . . . . . . . 1%
Range. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 100% RH
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±3% (0 to 90% RH), ±4% (90 to 100% RH)
Temperature Coefficient . . . . . . . . . . . . . . . . . . . . . . 0.03% per °F (0.05% per °C), reference 68°F (20°C)
Drift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.5% per year
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 seconds
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . Instant (user-adjustable offset available)
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . Instant and Hourly Reading; Daily, Monthly High and Low
Historical Graph Data . . . . . . . . . . . . . . . . . . . . . . . .Hourly Readings; Daily, Monthly Highs and Lows
Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .High and Low Threshold from Instant Reading

Moon Phase
Console Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1/8 (12.5%) of a lunar cycle, 1/4 (25%) of lighted face on console
WeatherLink Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . 0.09% of a lunar cycle, 0.18% of lighted face maximum (depends on
screen resolution)
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full
Moon, Wanning Gibbous, Last Quarter, Waning Crescent
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±38 minutes

Rainfall
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.01" or 0.2 mm with optional metric adapter (included) (Console
rounds 1 mm if rain totals are 2000 mm or higher)
Daily/Storm Rainfall Range . . . . . . . . . . . . . . . . . . . . . . . 0 to 99.99" (0 to 9999 mm)
Monthly/Yearly/Total Rainfall Range. . . . . . . . . . . . . . . . . 0 to 199.99" (0 to 19999 mm)
Rain Rate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 199.99" (0 to 19999 mm)
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .For rain rates up to 2"/hr (50 mm/hr): ±4% of total or +0.01" (0.2 mm)
(0.01" = one tip of the bucket, 0.2 mm with metric adapter), whichever
is greater.
For rain rates from 2"/hr (50 mm/hr) to 4"/hr (100 mm/hr): ±5% of total
or +0.01" (0.2 mm) (0.01" = one tip of the bucket, 0.2 mm with metric
rain adapter), whichever is greater.
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 seconds
Storm Determination Method . . . . . . . . . . . . . . . . . . . . . . 0.02" (0.5 mm) begins a storm event, 24 hours without further
accumulation ends a storm event
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . Totals for Past 15-min
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Totals for Past 15-min, Past 24-hour, Daily, Monthly, Yearly (start date
user-selectable) and Storm (with begin date); Umbrella is displayed
when 15 minute total exceeds zero
Historical Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . Totals for 15-min, Daily, Monthly, Yearly (start date user-selectable)
and Storm (with begin and end dates)
Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High Threshold called "Flash Flood" (15-min. Total, default is 0.50",
12.7 mm), 24-hour Total, Storm Total
Range for Rain Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 99.99" (0 to 999.7 mm)

Rain Rate
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.01" or 0.2 mm (with optional metric adapter (included)) at typical rates
(see Fig. 2 and 3)
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0, 0.04"/hr (1 mm/hr) to 100"/hr (0 to 1999.9 mm/hr)
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±5% or ±0.04"/hr (1 mm/hr) (up to 10"/hr. [250 mm/hr.]), whichever is
greater
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 seconds
Calculation Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Measures time between successive tips of rain collector. Elapsed time
greater than 15 minutes or only one tip of the rain collector constitutes
a rain rate of zero.
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant and 1-min. Reading; Hourly, Daily, Monthly, Yearly High
Historical Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-min Reading; Hourly, Daily, Monthly, Yearly Highs
Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High Threshold from Instant Reading

Solar Radiation (requires Solar Radiation Sensor)
2
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 W/m
2
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 1800 W/m
2
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±5% of full scale (Reference: Eppley PSP at 1000 W/m )
Drift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Up to ±2% per year
Cosine Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±3% for angle of incidence from 0° to 75°
Temperature Coefficient . . . . . . . . . . . . . . . . . . . . . . . . . -0.067% per °F (-0.12% per °C); reference temperature = 77°F (25°C)
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 seconds (5 minutes when dark)
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Reading and Hourly Average; Daily, Monthly High
Historical Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . Hourly Average, Daily, Monthly Highs
Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High Threshold from Instant Reading

Sunrise and Sunset
Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 minute
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±1 minute
Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States Naval Observatory

Temperature
Inside Temperature (sensor located in console)
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . Current Data: 0.1°F or 1°F or 0.1°C or 1°C.°(nominal). Celsius is
converted from Fahrenheit and rounded to the nearest 0.1° or 1°C.
Historical Graph Data and Alarms: 1°F or 1°C. Celsius is converted
from Fahrenheit and rounded to the nearest 1°C.
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +32° to +140°F (0° to +60°C)
Sensor Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . ±1°F (±0.5°C) typical
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 minute
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . Instant (user-adjustable offset available)
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . Instant; Daily and Monthly High and Low
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . Hourly Readings; Daily and Monthly Highs and Lows
Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High and Low Thresholds from Instant Reading
Outside Temperature (sensor located in ISS)
Resolution and Units. . . . . . . . . . . . . . . . . . . . . . . . .Current Data: 0.1°F or 1°F or 0.1°C or 1°C.°(nominal). Celsius is
converted from Fahrenheit and rounded to the nearest 0.1° or 1°C.
Historical Graph Data and Alarms: 1°F or 1°C. Celsius is converted
from Fahrenheit and rounded to the nearest 1°C
Range. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40° to +150°F (-40° to +65°C)
Sensor Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . ±1°F (±0.5°C) typical (see Fig. 1)
Radiation Induced Error . . . . . . . . . . . . . . . . . . . . . . +4°F (2°C) at solar noon (insolation = 1040 W/m , avg. wind speed <
2 mph (1 m/s)) (reference: RM Young Model 43408 Fan-Aspirated
Radiation Shield)
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 seconds
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . Instant (user-adjustable offset available)
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . Instant Reading; Daily, Monthly, Yearly High and Low
Historical Graph Data . . . . . . . . . . . . . . . . . . . . . . . .Hourly Readings; Daily and Monthly Highs and Lows
Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .High and Low Thresholds from Instant Reading

Temperature Humidity Sun Wind Index (requires Solar Radiation Sensor)
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1°F or 1°C. Celsius is converted from Fahrenheit and rounded to the
nearest 1°C.
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -90° to +135°F (-68° to +64°C)
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±4°F (±2°C) (typical)
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 seconds
Sources and Formulation Used . . . . . . . . . . . . . . . . . . . .United States National Weather Service (NWS)/NOAA
Steadman (1979) modified by US NWS/NOAA and Davis Instruments
to increase range of use
Variables Used. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Outside Temperature, Instant Outside Relative Humidity, 10-
minute Average Wind Speed, 10-minute Average Solar Radiation
Formulation Description . . . . . . . . . . . . . . . . . . . . . . . . . .Uses Heat Index as base temperature. Effects of wind and solar
radiation are either added or subtracted from this base to give an
overall effective temperature
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant and Hourly Calculation; Daily, Monthly Highs
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . . . . .Hourly Calculation; Daily, Monthly Highs
Alarm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .High Threshold from Instant Reading

Ultra Violet (UV) Radiation Dose (requires UV Sensor)
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 MEDs to 19.9 MEDs; 1 MED above 19.9 MEDS
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 199 MEDs
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±5% of daily total
Drift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . up to ±2% per year
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 seconds to 1 minute (5 minutes when dark)
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Latest Daily Total (user resettable at any time from Current Screen)
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . . . . .Hourly, Daily Totals (user reset from Current Screen does not affect
these values)
Alarm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .High Threshold from Daily Total
Alarm Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 19.9 MEDs

Ultra Violet (UV) RadIatIon Index (requires UV Sensor)
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 Index
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 16 Index
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±5% of full scale (Reference: Yankee UVB-1 at UV Index of 10
(extremely high))
Cosine Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±4% (0° to 65° incident angle); 9% (65° to 85° incident angle)
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 seconds (5 minutes when dark)
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant and Hourly Average; Daily, Monthly High
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . . . . .Hourly Average, Daily, Monthly Highs
Alarm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .High Threshold from Instant Calculation

Wind
Wind Chill (Calculated)
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . 1°F or 1°C. Celsius is converted from Fahrenheit and rounded to the
nearest 1°C
Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -110° to +130°F (-79° to +54°C)
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±2°F (±1°C) (typical)
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 seconds
Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States National Weather Service (NWS)/NOAA
Equation Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Osczevski (1995) (adopted by US NWS in 2001)
Variables Used. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Outside Temperature and 10-min. Avg. Wind Speed
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . Instant Calculation
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . Instant Calculation; Hourly, Daily, Monthly Low
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . Hourly, Daily, Monthly Lows
Alarm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Low Threshold from Instant Calculation
Wind Direction
Display Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . 16 points (22.5°) on compass rose, 1° in numeric display
Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±4°
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 seconds
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . Instant (user-adjustable offset available)
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . Instant; 10-min. Dominant; Hourly, Daily, Monthly Dominant
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . Past 6 10-min. Dominants on compass rose only; Hourly, Daily,
Monthly Dominants
Wind Speed
Resolution and Units . . . . . . . . . . . . . . . . . . . . . . . . Measured in 1 mph. Other units are converted from mph and rounded
to nearest 1 km/h, 0.1 m/s, or 1 knot
Range (large wind cups, included) . . . . . . . . . . . . . . 2 to 150 mph, 2 to 130 knots, 1 to 67 m/s, 3 to 241 km/h
Range (small wind cups; optional, not included) . . . . 3 to 175 mph, 3 to 150 knots, 1.5 to 79 m/s, 5 to 282 km/h
Update Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instant Reading: 2.5 seconds, 10-minute Average: 1 minute
Accuracy (large wind cups, included) . . . . . . . . . . . . ±2 mph (2 kts, 3 km/h, 1 m/s) or ±5%, whichever is greater
Accuracy (small wind cups; optional, not included) . . ±3 mph (3 kts, 5 km/h, 1.5 m/s) or ±5%, whichever is greater
Maximum Cable Length . . . . . . . . . . . . . . . . . . . . . . 240' (73 m). Maximum wind speed reading decreases as length of
cable from Anemometer to the ISS increases. At 140' (42 m), maximum
speed is 135 mph (60 m/s). At 240' (73 m), the maximum is 100 mph.
Current Display Data . . . . . . . . . . . . . . . . . . . . . . . . Instant
Current Graph Data . . . . . . . . . . . . . . . . . . . . . . . . . Instant; 10-minute and Hourly Average; Hourly High; Daily, Monthly,
Yearly High with Direction of High
Historical Graph Data. . . . . . . . . . . . . . . . . . . . . . . . 10-min. and Hourly Averages; Hourly Highs; Daily, Monthly, Yearly
Highs with Direction of Highs
Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High Thresholds from Instant Reading and 10-minute

MeteoHeerhugowaard

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