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Manual Data Storage
To manually store data, press the
button. One of the following will appear: Data Stored (data has been captured
and will appear on chart), Full (Overwrite is off and data log is full), or Off (Manual Store button has been disabled).
See the Main Setup Menu section for more information on Memory.
Backlight
Press the
button to activate the backlight. The light will remain activated for one minute. Press the
within one minute to deactivate the light manually.
Relative Humidity
The Kestrel 4300 is capable of measuring RH to a high accuracy: +/- 3% RH. To ensure the Kestrel 4300's ability to
operate within these specifications, follow these recommendations:
• Avoid taking measurements in direct sunlight, which will heat the air inside the humidity sensor enclosure
and cause inaccurate readings.
• If your circumstances force you to expose the Kestrel to a large temperature swing prior to taking a relative
humidity reading (such as when taking a Kestrel stored inside at 70° F outside to a temperature of 40° F), you will
need to take additional steps to ensure that the Kestrel's external temperature sensor is in thermal equilibrium.
- Ideally, provide an airflow of at least 1 M/S (2.2 MPH), over the temperature sensor, moving from the back
of the unit towards the front. (In other words, point the Kestrel into the airflow.) If there is no airflow, simply
wave the Kestrel back and forth so air passes over the sensors. With airflow over the temperature sensors
and humidity chambers, readings within specifications will be provided within two to three minutes, even
after a large temperature shift.
- If no airflow can be provided, you must allow sufficient time for the RH value to stabilize. This can take as long
as 20 minutes- the greater the temperature change, the greater the time. You can use the logging capability
of the Kestrel 4300 to confirm that the unit has stabilized to a correct reading: Set the memory options to
a relatively short logging interval (20 seconds works well, see Main Setup Menu for more information),
select the graphical display of RH, and you can see when the value is no longer changing significantly. At
that point, the RH value is stable and can be relied upon to be within the accuracy specifications.
Again, allow the Kestrel to stabilize, then enter the value from the BARO screen as your reference pressure on the
ALTITUDE screen by following the same procedure. Both readings are now accurate.
When reviewing stored data, remember that changes in pressure AND changes in location/altitude will affect the
stored values. When tracking pressure changes relative to weather, set the reference altitude on the BARO screen
and keep the Kestrel in one location. Your graph history will now show trends in barometric pressure. Your altitude
as shown on the ALTITUDE screen will change as the weather changes, but you can ignore this screen for this
purpose.
If you are planning a day hike would like to track your altitude, you'll need to enter the correct reference pressure
on the ALTITUDE screen as described above in "starting with the known barometric pressure." You can now track
the altitude changes as you hike. In this instance, you should ignore the values on the BARO screen, since the
pressure changes will be due to changes in elevation far more than to changes in the weather.
In general, changes in barometric pressure associated with weather changes are small over the course of one day,
but they will affect the accuracy of the altimeter over time. This is why aircraft reset their altimeters at every
airfield by entering the field's "altimeter setting" or reference pressure. Accordingly, if accurate altitude readings
are your primary interest, you should reset the reference pressure on your Kestrel regularly. If you encounter an
elevation landmark, you can adjust the reference pressure until the altitude matches the landmark elevation. This
will correct the altitude for any pressure changes due to the weather. (Or, you can obtain an updated reference
pressure from the sources described above.)
Some final notes - If you wish to know the actual or station pressure for your location (such as for engine tuning),
simply set the reference altitude on the BARO screen to "0" . In this case, the Kestrel will not make any adjustment
and will display the measured value. And, the above discussion applies to ALL pressure altimeters, including one
you may have in a watch or other device, but not to GPS altimeters which use satellite triangulation to determine
altitude. Note that with present GPS technology, pressure altimeters remain more accurate for measuring altitude
change. This is why airplanes still rely on pressure altimeters, not GPS. Finally, the DENSITY ALTITUDE screen is
calculated from the absolute values of station pressure, relative humidity and temperature, and is not affected by
the reference values entered in the BARO and ALTITUDE screens.
Barometric Pressure and Altitude Adjustment
The Kestrel 4300 measures station pressure - the actual air pressure in the measurement location - and uses this
value to calculate barometric pressure and altitude. Station pressure changes in response to two things - changes
in altitude and changes in the atmosphere. Because the Kestrel 4300 is constantly changing location and altitude,
it is important to enter adjustments or "references" when accurate pressure and altitude readings are needed.
button
Barometric pressure is station pressure corrected to sea level. In order to make the correction, the Kestrel 4500
needs an accurate reference altitude. Altitude is the height above sea level. In order to correctly calculate
altitude, the Kestrel 4500 needs an accurate barometric pressure reference, also known as an "altimeter setting" .
You only need to know ONE of these values (current barometric pressure or current altitude) in order to set your
Kestrel up to show accurate readings.
Starting with the known barometric pressure for your location
You can obtain your current barometric pressure by checking an internet weather site for a
nearby location, or contacting a local airport. Set this value as your reference pressure on the
ALTITUDE screen to determine your correct altitude: Press the
setting mode. Press the button to increase the reference pressure or the button to decrease
the reference pressure. You will notice that the altitude will change with changes in the reference pressure.
Press the
button to exit the adjustment mode. Set your Kestrel down on a table and allow the altitude reading
to stabilize. (Note: very small changes in pressure generate noticeable changes in altitude. In order to provide
meaningful readings for activities where altitude changes quickly, the Kestrel 4000 features rapid altitude
response. This is why the altitude readings tend to fluctuate by a few feet.) After obtaining a current altitude
from the ALTITUDE screen, move to the BARO screen and enter this value as your reference altitude by following
the same procedure. Both readings will now be accurate.
Starting with a known altitude for your location
You can obtain your altitude from a topographical map or local landmark. Google Earth is an
excellent free program that provides the exact altitude for any given address:
earth.google.com/. Set this value as your reference altitude on the BARO screen to determine
your barometric pressure: Press the
button to increase the reference altitude or the
that the barometric pressure will change with changes in the reference altitude. Press the
adjustment mode.
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You can customize your Kestrel 4500 in multiple ways. Press the
the
button to select the highlighted setting. The Main Setup Menu contains: OFF, Memory Options,
Measurements, Graph Scale, Units, User Screens, System, Date & Time, Language and Restore.
Off - Press the
or the
button to turn the display off. Even when the Kestrel's display is turned off, the unit
will continue to automatically store data at the defined Store Rate. Wind speed will NOT be stored when the
unit is off. To continuously measure wind speed, turn the auto shutdown off, and see page 8 for more information
on how this data is stored. The battery life will be decreased if data is stored frequently. The only way to completely
shut off the unit is to remove the batteries. Custom settings and data will be stored when the batteries are
removed.
Memory Options - These settings control the data storage properties.
Setting
Description
Clear Log
All stored data is cleared. This will also clear Min/Max/Avg data.
(Go/Done)
Reset MMA
All Min/Max/Avg data is cleared. Chart data will remain intact.
(Go/Done)
Auto Store
When On, data is automatically stored at preset Store Rate. When Off,
(On/Off )
data is only stored when manually captured with the
Store Rate* The frequency at which data sets are automatically stored.
(2 sec - 12 hr)
(Battery life may be shortened if data is stored frequently.)
Overwrite
This setting only applies when the data log is full. When On, oldest
(On/Off )
data point is discarded to allow memory for the new data point.
When Off, new data points are not saved.
Man Store
When On, data is stored when the
(On/Off )
When off, the
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* When unit is off, data is NOT stored for 2 sec and 5 sec Store Rates.
button to enter the reference
button to enter the reference setting mode. Press the
button to decrease the reference altitude. You will notice
button to access the Main Setup Menu. Press
button.
button is pressed.
button is disabled.
button to exit the
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Operation
Press
or to clear
the log.
Press
or to clear
the MMA.
Press
or to toggle
between On and Off.
Press
or to increase or
decrease Store Rate frequency.
Press
or to toggle
between On and Off.
Press
or to toggle
between On and Off.
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