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AIR PRESSURE HIST ORY GRAPH
The LCD shows the relative air pressure value and the air pressure history on a bar graph.
Press the SET button to toggle between Mode1 and Mode2 of the display.
•
Mode 1:
The bar graph displays the air pressure history of the
past 24 hours in seven steps. The horizontal axis represents the
last 24 hours of air pressure recording (-24, -18, -12, -8, -6, -3 and
0 hour).
•
Mode 2:
The bar graph displays the air pressure history of the
past 72 hours in seven steps. The horizontal axis represents the
last 72 hours of air pressure recording (-72, -48, -36, -24, -12, -6
and 0 hour).
The vertical bars are plotted at each of the seven steps and give the trend over the recorded period. The
0 hour vertical bar will always display at the midline height to indicate the current air pressure. The
varying height of bars in other columns on the graph indicates a relative change in air pressure up or
down from the 0 hour.
New pressure measurements are compared to previously recorded pressure measurements. The
pressure change is expressed by the difference between the current ("0h") and the past readings in
divisions of ±0.06 inHg or ±2 hPa. If the bars are rising from left to right, this indicates that the weather is
getting better due to an increase in air pressure. If the bars are falling from left to right, this indicates that
the weather is expected to get worse due to a drop in air pressure.
At every full hour, the current air pressure is used as a basis for the display of a new graph bar. The
existing graph is then moved one column to the left.
Note:
For accurate barometric pressure trend, the weather station should operate at the same
altitude. Should the unit be moved (for instance, from the ground to the second floor of the house), the
readings for the next 48-60 hours should be discarded.
Note:
The bar graph will scroll right to left regularly to prevent LCD burnout.
WIND DIRECT ION AND WIND SPEED MEASUREMENT
•
The longest pointer on the outer circle of the compass indicates the
current wind direction.
•
The last 6 wind directions may be displayed with shorter pointers on
the inner circle.
•
The wind direction (abbreviation or degrees) is displayed in center of
compass.
Press the SET button to toggle between Mode1 and Mode 2 of the
display.
Mode 1
displays the following wind data:
•
Wind direction
•
Wind chill in
°
F or
°
C
•
Wind
speed
in mph, km/h, bft, knots or m/s
Mode 2
displays the following wind data:
•
Wind direction
•
Wind chill in
°
F or
°
C
•
Wind
gust
in mph, km/h, bft, knots or m/s
RAINF ALL MEASUREMENT
