Water Leak Sensor WS303 – Milesight WS303

The WS303 is a mini water leak detection sensor designed for early warning when leaks, spills, or floor wetness occur. When conductive liquid bridges its probes, it triggers an audible buzzer locally and sends an alert over LoRaWAN—so teams can act immediately even when the site is unattended.

Detection is based on liquid conductivity and can alarm from a 0.5 mm liquid level, making it well-suited for common real-world risk points: under sinks, near condensate drains, beneath HVAC units, around pumps, and inside plant rooms. It’s a practical choice for facility management rollouts where simple installation and long battery life matter.

The WS303 also supports Milesight D2D (device-to-device) communication, enabling Milesight nodes to interact directly without a LoRaWAN gateway for low-latency local actions (depending on your D2D setup). A capacitor-backed power failure alarm helps surface outages that could otherwise go unnoticed. With IP67 protection and corrosion-resistant probe design, it’s built for demanding environments.

Typical deployments: data centers and server rooms, HVAC and plant rooms, commercial buildings, restrooms, hotels, schools, and equipment areas where small leaks can escalate quickly.