What is the purpose of weather sensors in irrigation control?

• A. They provide rainfall data to trigger automatic shutoff
• B. They measure soil moisture directly
• C. They regulate fertilizer application
• D. They provide input signals to the controller to adjust irrigation

Answer: (D)

Weather sensors feed the irrigation controller with real-time conditions so the system can respond to changing plant water needs. They commonly monitor rainfall, temperature, humidity, wind, and sometimes solar radiation. The controller uses this information to adjust irrigation timing and amount, such as delaying or reducing watering after rain or during cooler, wetter periods, and increasing or scheduling more watering when conditions drive higher water demand. In short, the main purpose is to provide input signals to the controller to optimize irrigation.

While rainfall data can trigger a shutoff in some setups, that’s a specific application of the same idea: the sensor data informs the controller to change irrigation operations.