Casio 2891 Operation Manual page 11

Calibrating the Pressure Sensor
The barometric pressure sensor of the watch is calibrated at the factory, and further calibration normally is not required. Perform the
following operation only when you find that a pressure reading taken with another accurate instrument is very different from the reading
produced by your watch. Take care that you perform the calibration operation correctly. Using the wrong value can make it impossible to
measure barometric pressure correctly.
1.
Pressure
In the Pressure/
Temperature Mode, hold
down the E E button for E E E
about two seconds until
"OFF" or the current
temperature appears at
the bottom of the display.
• It will take four to five seconds
for the barometric pressure
(2 seconds)
value to appear.
Temperature
2.
Press the D D D D D button so
"OFF" or the barometric
pressure value is flashing.
Barometric Pressure Primer
❚ Ways you can use the pressure tendency graph
Example 1: Hiking
You can take barometric pressure
readings from morning to night the
day before you plan to go hiking or
mountain climbing, and get an idea
of what the weather will be like.
❚ Predict weather based on changes in barometric pressure.
Barometric pressure changes along with atmospheric movements. Because of this, you can predict upcoming weather by monitoring
changes in barometric pressure.
If barometric pressure is rising ➔ Weather conditions should improve
If barometric pressure is falling ➔ Weather conditions should deteriorate
Why this is true
High Pressure Sky
A rise or fall in
Downward flowing
barometric pressure
air dissipates clouds
produces changes in
and clears the skies.
Downward Air Flow
the weather as shown
to the right.
High Pressure
❚ Atmospheric Pressure
The barometric pressure values reported on TV, in newspapers, and in other media are actual readings taken on mountains, plains, and
the sea, which are converted to a mean sea level pressure value. They are not the barometric pressure values for mountain areas. This
makes it possible to compare barometric pressure values regardless of location. The process of correcting barometric pressure to a fixed
altitude (sea level) is called "reduction to sea level".
Operation Guide 2891
3.
Use the C C (+) and A C C C A A A A (–)
buttons to adjust the
barometric pressure
value.
• Each press of the C button
or A button changes the
displayed value by 1hPa.
• Holding down either button
scrolls the setting at high
speed.
• Pressing the C and A
buttons at the same time
returns to the factory default
setting, which is indicated by
"OFF".
4.
After the setting is the
way you want, press the
E E button to return to the E E E
Pressure/Temperature
Mode screen.
• The watch automatically exits
the pressure sensor
calibration screen if you do
not perform any operation for
about two or three minutes.
Example 2: Golf
Changes in barometric pressure can
alert you to an approaching
thunderstorm and keep you safe.
Low Pressure Sky Clouds
Upward flowing air
produces clouds,
which cause rain.
Upward Air Flow
Ground
Ground
Low Pressure
Calibrating the Temperature Sensor
The temperature sensor is calibrated at the factory, and further calibration normally is not required. Perform the following operation only
when you find that a temperature reading taken with another accurate instrument is very different from the reading produced by your
watch. Take care that you perform the calibration operation correctly. Using the wrong value can make it impossible to measure
temperatures correctly.
1.
(–) Pressure
In the Pressure/
Temperature Mode, hold
down the E E E E E button for
about two seconds until
"OFF" or the current
temperature appears at
the bottom of the display.
(+)
• It will take four to five seconds
for the barometric pressure
(2 seconds)
value to appear.
2.
Use the C C (+) and A C C C A (–) A A A
buttons to adjust the
temperature value.
• Each press of the C button
or A button changes the
displayed value by 0.1 o C.
• Holding down either button
scrolls the setting at high
speed.
• Pressing the C and A buttons at the same time returns to
the factory default setting, which is indicated by "OFF".
3.
After the setting is the way
you want, press the E E E E E
button to return to the
Pressure/Temperature
Mode screen.
• The watch automatically exits the temperature sensor
Temperature
calibration screen if you do not perform any operation for
about two or three minutes.
(–)
(+)
11