Rain Delay is a manual control – it stops the controller from watering for a specified amount of time. Rain Sensor requires installing an external rain sensor, and it stops the controller from watering when the sensor detects rain. Weather-based Adjustment makes use of real-time data at your nearby weather stations, and automatically calculates a watering percentage that combines not only information about rain but also temperature and humidity. Although these three features are conceptually related, they are independent. See the chart below:
Trigger | Action | Delay Time | Notes |
Rain sensor | Stations (except those that ignore rain) will stop watering when the sensor reports rain. | Rain sensor has a built-in mechanical delay, adjustable by opening/closing evaporation vents on the sensor. | Stations that are stopped, or scheduled to run during the delay time will NOT restart or resume after the delay time is over. |
Change | Manual. Stations (except those that ignore rain) will stop watering during the specified rain delay time. | Specified by the user. | |
Weather-based Adjustment | Water time is scaled by a watering percentage value (0% to 250%), updated every 15 minutes. | No explicit delay time. Water time may decrease (<100%) or increase (>100%) based on weather. | Accuracy depends on the proximity of your closest weather station. |