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E-63
Barometric Pressure Change Indications
Your watch analyzes past barometric pressure readings and uses a barometric pressure change indicator
to inform you about changes in pressure. If the watch detects a signifi cant change in barometric pressure,
it will beep and display a fl ashing arrow that indicates the direction of the pressure change. This means
you could start taking barometric pressure readings after reaching a lodge or camp area, and then check
the watch the next morning for changes in pressure, and plan you day’s activities accordingly. Note that
you can enable or disable display of the barometric pressure change indicator as desired.
The barometric pressure change indicator is displayed in the Barometer Mode and while the barometric
pressure graph is displayed in the Timekeeping Mode (page E-23).
Reading the Barometric Pressure Change Indicator
Indicator Meaning
Sudden fall in pressure.
Sudden rise in pressure.
Sustained rise in pressure, changing to a fall.
Sustained fall in pressure, changing to a rise.
• The barometric pressure change indicator is not displayed if there has been no noteworthy change in
barometric pressure.
E-62
Reading Barometric Pressure Differential Pointer
Pressure differential is indicated in the
range of ±10 hPa (0.3 inHg), in 1-hPa (0.03
inHg) units.
• The nearby screen shot, for example,
shows what the second hand would
indicate when the calculated pressure
differential is approximately – 5 hPa
(approximately –0.15 inHg).
• The second hand will point to
OVER
(
) or
UNDER
( ) if the
barometric pressure differential is
outside the allowable range of the scale.
• The second hand will move to 9 o’clock
if a sensor reading could not be taken
for some reason or if the reading is
outside the allowable range.
• Barometric pressure is calculated and
displayed using hPa as the standard.
The barometric pressure differential also
can be read in inHg units as shown in
the illustration (1 hPa
=
0.03 inHg).
Current pressure greater
than most recent
measured pressure
Current pressure
less than most
recent measured
pressure
inHg values
hPa values
Barometric
pressure
differential
pointer
–10
–5
–0.15
–0.3
00
0.15
0.3
10
5
E-61
Barometric Pressure Differential Pointer
This pointer indicates the relative difference between the most recent
barometric pressure reading indicated on the barometric pressure graph
(page E-59), and the current barometric pressure value displayed in the
Barometer Mode (page E-58).
To show and hide barometric pressure differential
1. Use
B
to enter the Barometer Mode (
BARO
), as shown on page E-20.
2. Press
D
.
Note
• Press
D
to toggle the second hand between its two functions (indicating seconds or indicating the
barometric pressure differential).
Barometric
pressure
differential
pointer
E-60
Reading the Barometric Pressure Graph
The barometric pressure graph shows a chronological history of pressure readings.
• The horizontal axis of the graph represents time, with each dot
standing for two hours. The rightmost dot represents the most recent
reading.
• The vertical axis of the graph represents barometric pressure, with
each dot standing for the relative difference between its reading and
that of the dots next to it. Each dot represents 1 hPa.
The following shows how to interpret the data that appears on the barometric pressure graph.
Rising barometric pressure indicates that upcoming weather will improve.
Falling barometric pressure indicates that upcoming weather will deteriorate.
Note
• If there are sudden changes in weather or temperature, the graph line of past
readings may run off the top or bottom of the display.
• The following conditions cause the barometric pressure reading to be skipped, with
the corresponding point on the barometric pressure graph being left blank.
– Barometric reading that is out of range (260 hPa to 1,100 hPa or 7.65 inHg to 32.45
inHg)
– Sensor malfunction
• The barometric pressure graph is not displayed while the barometric pressure change indicator is
displayed.
Barometric
pressure
Time
Not visible on
the display.
E-59
Barometric Pressure
• Barometric pressure is displayed in units of 1 hPa (or 0.05 inHg).
• The displayed barometric pressure value changes to
- - -
if a measured
barometric pressure falls outside the range of 260 hPa to 1,100 hPa
(7.65 inHg to 32.45 inHg). The barometric pressure value will reappear
as soon as the measured barometric pressure is within the allowable
range.
Display Units
You can select either hectopascals (hPa) or inchesHg (inHg) as the
display unit for the measured barometric pressure. See “To specify
altitude, barometric pressure, and temperature units” (page E-41).
Barometric Pressure Graph
Barometric pressure indicates changes in the atmosphere. By monitoring
these changes you can predict the weather with reasonable accuracy.
This watch takes barometric pressure reading automatically every two
hours. Readings are used to produce barometric pressure graph and
barometric pressure differential pointer readings.
Barometric pressure
change indicator
Barometric pressure
Barometric pressure graph
E-58
Taking Barometric Pressure Readings
This watch uses a pressure sensor to measure air pressure (barometric pressure).
To take barometric pressure readings
Use
B
to select the Barometer Mode (
BARO
), as shown on page E-20.
•
BARO
will appear on the display, indicating that barometric pressure
reading is in progress. The results will appear on the display after
about one second.
• After a barometric pressure reading operation is started, the watch will
take readings every fi
ve seconds for the fi rst three minutes, and then
every two minutes after that.
• To restart a reading operation from the beginning, press
A
.
• The watch will return to the Timekeeping Mode automatically if you do
not perform any operation for about one hour after entering the
Barometer Mode.
Note
• When you press
B
above, the second hand may indicate seconds (of
the current time) or the barometric pressure differential (page E-61). The
initial second hand function will be the same as what was selected the
last time you took a barometric pressure reading. To toggle between
the two second hand functions (indicating seconds or indicating the
barometric pressure differential) press
D
.
Barometric
pressure graph
Barometric
pressure
E-57
Precautions Concerning Simultaneous Altitude and Temperature Readings
For the more accurate altitude readings, leaving the watch on your wrist is recommended in order to
maintain the watch at a constant temperature.
• When taking temperature readings, keep the watch at as stable a temperature as possible. Changes in
temperature can affect temperature readings. See product specifi
cations (page E-95) for sensor accuracy
information.
E-56
Altimeter Precautions
• This watch estimates altitude based on air pressure. This means that altitude readings for the same
location may vary if air pressure changes.
• Do not use this watch for altitude reading or perform button operations while sky diving, hang gliding,
or paragliding, while riding a gyrocopter, glider, or any other aircraft, or while engaging in any other
activity where there is the chance of sudden altitude changes.
• Do not use this watch for measuring altitude in applications that demand professional or industrial level
precision.
• Remember that the air inside of a commercial aircraft is pressurized. Because of this, the readings
produced by this watch will not match the altitude readings announced or indicated by the fl
ight crew.
Operation Guide 5497
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