La Crosse Technology WS-9020U 915MHZ instruction manual Hysteresis, Alarm setting Minimum Maximum

can set the thresholds for the outdoor temperature to +104°F (+40ºC) (high) and +14ºF

(-10°C) (low), while only enabling the high alarm and disabling the low alarm (i.e. temperatures < +14ºF (-10°C) won’t trigger alarm, but temperatures > +104ºF (+40°C) will).

Alarm setting	Minimum	Maximum
Outdoor Temperature	-40°F (40ºC)	+139.8°F (59.9ºC)

HYSTERESIS

To compensate for fluctuation of the measured data, which may cause the weather alarm to sound constantly if the measured reading is close to user set level, a hysteresis function has been implemented for each weather alarm. For example, if the high temperature alarm is set to +77°F (+25°C) and the current value moves to +77°F (+25°C), the alarm will be activated (if it has been enabled). Now when the temperature drops to +76.8°F (+24.9°C) or below and thereafter again increases to beyond +78°F (+25°C), the data will be blinking, but no alarm will be activated. It has to drop to below +75.2°F (+24°C) (with a pre-set hysteresis of 2ºF (1°C)) so that the alarm can be produced again. Hysteresis values for the various weather data types are given in the following table:

Weather data	Hysteresis
Temperature	2°F
Humidity	3% RH
Air pressure	0.03 inHg

WEATHER FORECAST AND WEATHER TENDENCY: WEATHER FORECASTING ICONS:

There are 4 weather icons in the fourth section of LCD which can be displayed in any of the following combinations:

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