ESP32 and MQTT Prototype Aims to Detect Water Leaks Through Connected Sensing

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A tutorial outlines how to build an educational water leak detection prototype using an ESP32 microcontroller, a digital water-contact sensor, Wi-Fi, and the MQTT messaging protocol. The system reads wet or dry states from the sensor, publishes confirmed changes and periodic status updates to an MQTT broker, and lets other applications subscribe to those messages. The author stresses that the design is a monitoring prototype rather than a certified water protection system. The guide also covers sensor debouncing, network failure handling, security, and possible improvements. It recommends checking sensor voltage compatibility, since 5 V outputs should not be connected directly to the ESP32's 3.3 V GPIO pins.

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