May 12, 2026 · 8 min read · by SprinklerMap Team
Rain sensor for irrigation: legal requirement and how it works
Rain sensors are legally required in Italy on all automatic irrigation systems. How they work, where to mount them, and how to wire them.
Legal requirement and how it works
Italian law (Decree 152/2006) requires a rain sensor on every automatic irrigation system. The sensor contains hygroscopic discs that expand when wet, opening a contact that interrupts the controller signal. After drying (4–24 h) the contact closes and the system resumes.
Mount at 1.5–2.5 m in a location exposed to direct rain. Remove the jumper from the controller SENS terminals before wiring.
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