8. Sensor
112
Using the altimeter
Applicable modes:
You can check the altitude of the current location.
Altimeter is not adjusted at the time of purchase.
• Displaying range is
j
500 m (
j
1640 feet) to 9000 m
(29530 feet).
A
Altitude
B
Current altitude
∫
About altitude conversion
The displayed altitude is a relative altitude
¢
1
. The altitude is a value calculated by
converting an atmospheric pressure within the unit to an altitude with 0 m (0 feet) (sea
level)
u
1013 hPa
¢
2
as a reference.
¢
1 Altitude can be expressed in two forms — as an altitude above sea level (absolute height
from sea surface) or as a relative altitude (difference in altitude between two locations). This
unit displays a relative altitude estimated by a method which uses the relationship between
the altitude and atmospheric pressure in the ISA [International Standard Atmosphere], as
specified by the ICAO [International Civil Aviation Organization].
¢
2 “hPa (hectopascal)” is a unit used to represent atmospheric pressure.
∫
About the measured altitude and atmospheric pressure
• Altitude value may show errors depending on the change in atmospheric pressure compared to
areas such as locations with altimeter reference signs. Adjust frequently with [Altimeter Adjust].
• Altitude announced onboard an airplane is measured using the atmospheric pressure
surrounding the airplane. It does not match the altitude actually measured inside the airplane.
• Even if the unit is fixed at a constant altitude, the measured altitude may fluctuate due to the
effects of change in atmospheric pressure.
In coastal areas, the altitude changes by 1 m (3.3 feet) per 0.12 hPa.
• Altitude and atmospheric pressure may not be measured
accurately in the following cases:
– When there is a significant change in weather conditions
(Pressure and air temperature)
– When there is a movement with a rapid change in altitude
– When pressure is applied to the front or rear of this unit
(Hold this unit as shown in the figure when measuring.)
– When this unit is wet (after using underwater, etc.)
¢
3
– When closing the side door
¢
3
¢
3 It will adapt to the ambient atmospheric pressure within a few minutes, and display correct
measurement values.
1
P
