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Wind Direction (accessory required)
This channel reports the direction of the wind. The Go Direct Weather Vane
accessory (order code WTHR-VANE) is required and mounting on a tripod is
recommended. Once attached, your Go Direct Weather will rotate such that the
wind will pass from the back of the sensor to the front. The direction from
which the wind is coming will be reported in 10° increments, with 360°
representing north and 90° representing east.
For the sensor to indicate true north at your location, the magnetic declination
must be set. Magnetic declination is the angular difference between true north
and the direction to which a magnetic compass points. This varies by location
and changes over time. Your current magnetic declination can be determined by
consulting any number of online calculators. It will consist of a numeric angular
value and identified as either East or West. If your declination is identified as
East, enter the value in the app as a positive number. If it is identified as West,
enter it as a negative number.
For example, Vernier’s main office is near Portland, Oregon. At the time of this
writing, its magnetic declination is 15° East. Therefore, the declination should
be entered as 15. Portland, Maine, on the other hand has a declination of 15°
West. Therefore, this would be entered as –15.
Follow these steps to set the magnetic declination for your location:
1. Connect your Go Direct Weather.
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In Graphical Analysis 4 app, click or tap on the sensor icon in the
bottom right corner of the application window. Click or tap the “i” next
to the sensor ID to launch the device information dialog.
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On LabQuest, tap the Wind Direction meter, tap Go Direct, and select
Device Details…
2. Select Advanced at the bottom of the window.
3. Enter the declination value for your location as a positive value for East and
a negative value for West.
4. Click or tap Save in Graphical Analysis 4 or Apply on LabQuest. The
declination value is stored in the sensor and is applied each time the sensor
is used.
Wind Chill
This channel reports the wind chill. Wind chill is a calculation that measures
how the wind and temperature impact the rate of heat loss from exposed skin.
Wind chill is defined only for ambient temperatures below 50°F and wind speed
greater than 3 mph. The reading is calculated based on an equation from the
National Weather Service where WC is the wind chill, T is temperature in °F
and W is wind speed in mph.
Temperature
This channel measures ambient temperature.
Connecting via USB
Connected and charging
Orange LED next to the battery icon is solid
when the sensor is connected to
Graphical Analysis via USB and the unit is char-
ging. LED next to Bluetooth icon is off.
Connected, fully charged
Green LED next to the battery icon is solid
when the sensor is connected to
Graphical Analysis via USB and fully charged.
LED next to Bluetooth icon is off.
Charging via USB,
connected via Bluetooth
Orange LED next to the battery icon is solid
when the sensor is charging. Green LED next to
the Bluetooth icon flashes.
Identifying the Sensor
When two or more sensors are connected, the sensors can be identified by
tapping or clicking Identify in Sensor Information.
Using the Product
Connect the sensor following the steps in the Getting Started section of the user
manual.
The sensor shows best performance when operated within recommended normal
temperature and humidity range of 5–60°C and 20–80% RH, respectively. Long-
term exposure to conditions outside normal range, especially at high humidity,
may temporarily offset the relative humidity reading.
Channels
Go Direct Weather has the following measurement channels:
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Wind Speed
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Wind Direction
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Wind Chill
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Temperature
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Heat Index
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Dew Point
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Relative Humidity
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Absolute Humidity
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Station Pressure
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Barometric Pressure
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Altitude
Wind Speed
This channel reports wind speed. The sensor uses an impeller-type anemometer
with the axis of rotation parallel to the direction of the wind. The motion of a
magnet in the impeller produces a signal proportional to wind speed. The
reading is positive regardless of the direction of motion of the impeller.
