SRC RANGER 4000 S, Инструкция по установке и устранению неисправностей

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Ranger S Installation and troubleshooting
23
Setting Hourly Maximum Rain and Rain Alarm
Level
The Ranger 4000 S allows for two precautions when you experience rain:
You can set a threshold value for how much it should rain before the rain
alarm will be activated. Here is how this calculation is done:
• Based on historical ET data for the area, the controller knows how
much water is evaporating per day during the current season.
• The Ranger 4000 S assumes that 75% of the daily ET is evaporating
between 8 and 20, and the remaining 25% between 20 and 8.
• When the amount of rain exceeds the rain alarm level you define,
the rain alarm is activated.
• Now, based on the historical ET data the controller will calculate
how much rain will evaporate, and mapping this number against the
known amount of fallen rain, the controller will intelligently know
when it is safe to turn off the rain alarm (i.e. when enough rain has
evaporated that we are below your defined alarm level.)
• The soil holding value is also a parameter: since you can never
benefit from more rain than the soil is capable of holding, the rain
alarm will not stay on forever after a few days of intensive rain.
• If it rains intensively for more than an hour you may get so much
water that the soil can not benefit from all of it ‐ the excess water
will simply run off the surface. So if you run programs in ET
corrected mode, the controller won't subtract all of the rain from
Note: If you have not provided any historical ET, a default of 5
mm per day is used. See more in the Ranger 4000 User Manual.