P a g e
| 27
The bars are plotted at each of the seven steps and give the trend over the recorded
period. The scale on the right compares the result. The "0" in the middle of this scale
determines the current air pressure.
The vertical axis represents the air pressure changes in inHg (+0.12, +0.06, 0, -0.06, -
0.12. The “0” represents the current air pressure). The newly measured pressure was
compared to the previously recorded pressure reading. The pressure change
is expressed by the difference between the current ("0h") and the past readings in
division of ±2 hPa or ±0.06 inHg. If the bars are rising, this indicates that the weather is
getting better due to an increase in air pressure. If the bars go down it indicates a drop
of the air pressure and the weather is expected to get worse from the present time "0".
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 Center should operate at
the same altitude. For example, it should not be moved. 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 shall be discarded.
Note:
The bar graph will scroll right to left regularly to prevent LCD burnout.
WIND DIRECTION AND WIND SPEED MEASUREMENT
In display Mode 1, LCD shows the following wind data:
x
Wind direction (shown on the compass scale of 16 divisions)
x
Wind chill in
q
F or
q
C
x
Wind
speed
in mph, km/h, bft, knots or m/s
In display Mode 2, LCD shows the following wind data:
x
Wind direction (shown on the compass scale of 16 divisions)
x
Wind chill in
q
F or
q
C
x
Wind
gust
in mph, km/h, bft, knots or m/s
RAINFALL MEASUREMENT
The 1hour, 24 hour, week, month or total rainfall measurement is displayed on the LCD,
in the unit of mm or inch.