25
RAIN SHUTOFF
THRESHOLD: .02 IN
IN ONE HOUR
Rain water fills a small internal cup in the sensor, which tips the buck-
et. For rain shutoff purposes, each tip is counted as one hundredth of
an inch or .254mm.
The preset rain shutoff amount is displayed as .02"/.51mm, which
is the minimum setting. This is sufficient for most applications, and
most users can skip this dial position.
In some areas with frequent short, heavy downpours of rain, or very
high concentrations of fog, the rain shutoff threshold can be adjusted
higher. Condensing fog or dew can accumulate enough to tip the buck-
et over the course of a few hours, the threshold is never set below two
tips of the sensor.
Use the +/- keys to change the rain shutoff threshold.
This setting applies to all stations. Turn the dial to save the Rain set-
ting. For initial setup, turn the dial to the ET setup position.
The rain setting amount is not exact. One tip of the bucket actually
equals .017"/.4318mm water, and ET System calculates the actual
totals internally using the exact value. Two tips would actually
equal .034"/.86mm of rain, and the ET System knows this.
However, the Rain Setting position displays these tips as rounded
inches, or millimeters, for general reference. This is only used for
the amount that will stop the sprinklers from running in the rain.
See the R24 explanation under View Sensor Data for a more com-
plete explanation of rain measurement.
If the Rain Sensor has caused the irrigation to pause, the ET System
display will show “RAIN PAUSE”. If rainfall ceases during the auto-
matic irrigation period, ET System may resume irrigating if the rainfall
was insufficient to fully replenish the soil reservoir. The system may
resume where it left off automatic irrigation, but with adjusted run
times for the amount of measured rainfall.
Rain Pauses always last for 15 minutes, after which ET System will
check the sensor again. If Rain is still detected, it will begin another
15 minute pause. This will continue until the Rain has stopped, and
ET System determines that watering is still required. If the measured
rainfall has replenished the soil fully, ET System will cancel the
remaining irrigation.
All sensor-based Pause modes (Rain, Freeze, and optional Wind) are
tracked in the watering history and will be reported for the days on
which they occurred.
ET Setup
The ET Setup dial position contains important settings that affect all
stations.
Enable ET
: Normally this is set to YES, and that is how the ET System
is designed to operate.
ENABLE ET: YES
UNITS: INCHES
ET SOURCE: SENSOR
ET ADJUST: 80%
If Enable ET is set to NO, the ET System will not irrigate at all. If
WiltGard was enabled (at the Daily Start Time dial position) it will also
be disabled, and when the dial is returned to the Automatic position,
the display will show OFF.
To disable ET, use the +/- key to change the display to ENABLE ET: NO.
The ET System display will then show OFF when the dial is returned
to the Automatic position, and no automatic irrigation (including Wilt-
Gard) will take place. Setting ET Enable to NO is one way of shutting
the system down for winter, or other extended periods.
Turning the host controller to Off will not stop ET System from run-
ning Program A! You must also disable ET in the ET System to stop
all irrigation for an extended period.
Summary of Contents for ET System
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