Controller Link
Controller Link is a simple upgrade for existing sprinkler timers to provide climate controlled irrigation. Controller Link saves water by managing irrigation, based on real-time weather conditions.

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Who Benefits from Weather Reach?

Quantifying Effective Rain

Don't water when it rains!  This is obvious.  But when do you irrigate after it rains?  When the rain evaporates.  
This sounds simple, but how much did it rain and how much of that rain was useful to the plants?
Weather Reach automates this complex process to conserve water and make sure plants are watered right. There are three key elements to solve this problem: 
  • Measure it - Rainfall must be measured.
  • Rain Source - Where do you take the measurement?
  • Effective Rain - What do Weather Reach Controllers do with the measurement?

Measure Rain

It is just as important to measure rain as it is to measure ET.  In many places there is more rain than evaporation, which makes the rainfall measurement the most important. 
The most common device used to measure rain is called a Tipping Rain Gauge (sometimes spelled gage).  A tipping rain gauge measures precipitation.  Rain falls into a collector on the top and funnels it to a tipping “bucket” or spoon.  Once the bucket fills with water it tips, causing a momentary switch closure.  As it tips the bucket is emptied and water drains out the bottom of the gauge.  Depending on the gauge, each “tip” or switch closure represents either 0.01” or 1-mm of rain.  Weather Reach Controllers count each tip.

Rain Source

Climate conditions affecting evaporation is the same over a broad region.  Rain on the other hand can be localized.  This is why Weather Reach Smart Controls use real-time rain measurements from one of three sources: 
  • Weather Station
  • Rain Station
  • On-Site Tipping Rain Gauge 
Note: There is a user selected setting called Rain Source in Controller Link and Rain Bird ET Managers.  Once selected this becomes the source of the rainfall measurement.  
Weather Station
Rain fall measurements recorded at the local ET Weather Station are retrieved by the Weather Reach Server.  Rainfall data is included with the hourly weather packet that is sent to Weather Reach Smart Controllers.  If the project is close to the station location, the rainfall measurements will provide accurate information.
Rain Station
Weather stations are expensive.  The ET Weather Station may be several miles from a project; the data from the station will provide accurate information to calculate evaporation, but the rainfall measurement may not be representative of the project location.  
In this case, a less expensive Rain Station may be installed at a project.  The rainfall measurements are retrieved by the Weather Reach Server and delivered to Weather Reach Smart Controller using the same communication path used by the ET Weather Station; via the Internet or Weather Reach Signal.  Measurements from one rain station will reach an unlimited number of Weather Reach Smart Controllers. 
On-Site Tipping Rain Gauge
The most accurate way to get a precise rainfall measurement is to use an on-site tipping rain gauge.  A Tipping Rain Gauges may be wired Weather Reach Smart Controllers that count each tip and record it as rain.

Effective Rain

A simple irrigation formula looks like this:
                         ET – Rain = Irrigation
But there is more to it.  How much of the rain was effective?  Effective rain is the amount of rain which is useful to the plant.  Several factors must be considered to quantify effective rain:
  • Rain that falls faster than the soil can absorb may run off.  
  • Soil moisture holding capacity is limited by soil type and root depth.  
  • The rain holding capacity of the soil is limited by the moisture content when it began to rain.  For example, if watering occurred just before a storm there is not much room left in the soil to hold the rain which limits the amount of useful rain. 
Weather Reach Smart Control quantifies effective rain using three tools:
  • Maximum Hourly Rain Limit – Rain in excess of this limit is considered to be run-off.
  • Saturation Allowance – How much extra water can the soil hold when it the soil is saturated.
  • Moisture Balance – For each program the moisture balance is tracking the amount of water since the last rain storm or watering.  Rain and irrigation are added to the Moisture Balance.  Evaporation depletes soil moisture.  Once soil moisture is depleted to the allowed level it will water. 
Weather Reach Smart Control waters right by tracking soil moisture: 
  • If it begins to rain just after watering, soil moisture is near capacity so not as much rain is effective.
  • It knows when the soil is saturated then lets it properly dry out to keep plants healthy.
  • By watering deep and less frequent, roots grow deep.  When roots are deep more rain will be available to the plants. 
All of this means, Weather Reach Smart Controllers know when irrigation should resume after it rains to more effectively eliminate wasteful over-watering.