How is an irrigation valve opened by the irrigation controller?

• A. Physical Turn
• B. Battery Activation
• C. Solenoid Activation
• D. Hydraulic Pressure

Answer: (C)

The irrigation valve is opened by the irrigation controller through solenoid activation. A solenoid is an electrical device that converts electrical energy into mechanical motion. When the irrigation controller sends a signal to activate the solenoid, it generates a magnetic field that pulls a plunger or armature, physically opening the valve.

This method allows for precise control over the watering schedule, enabling the system to operate automatically based on programmed settings, such as specific days and times for irrigation. The electrical signals from the controller are necessary for activating the solenoids, ensuring that water is delivered to the landscape at appropriate intervals, thereby enhancing water efficiency.

In contrast, while physical turns or hydraulic pressure may play roles in other contexts, they do not pertain to how modern irrigation systems are typically controlled. Battery activation alone refers to the power source rather than the mechanism of valve operation.