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3. Press the
Ÿ
UP ARROW key or
ź
DOWN ARROW key to set the 24 hour
rainfall alarm value.
4. Press the ALARM key to confirm the setting. The digit will stop flashing.
5. Press the SET key to switch on or off the alarm. The (((
y
))) icon indicates the
alarm is switched on.
6. Press the ALARM key to exit the alarm setting mode.
HYSTERESIS
To compensate for fluctuation of the weather data,
which may cause the weather alarm to ring
constantly if the measured reading is close to the
alarm level, a hysteresis function has been
implemented for each weather alarm.
For example, if the high temperature alarm is set to
77°F and the temperature reaches 77°F, the alarm will
be activated. If the temperature then drops to 76.8°F
(a change of less than 1.8°F) and then increases to
77°F again, the data will blink, but no alarm will be
activated.
The temperature would have to drop below 75.2°F (with a pre-set hysteresis of
1.8°F) so that the alarm can be produced again. Hysteresis values for the various
weather data types are given in the table.
Note:
The temperature or humidity data will keep flashing even after a
weather alarm has been switched off by a key press. The flashing value
indicates that the current weather condition is out of the pre-set weather alarm
limit(s).
Weather
data
Hysteresis
Temperature 1.8°F
Humidity 3%
RH
Pressure 0.029
inHg
Wind speed
6.2 mph
