Humidity sensor - resistive, analog, 3.3-5 V

Product Overview

• Resistive moisture sensor with two contact electrodes for soil or water
• 3-pin connection S/+/− for signal and power supply
• Analog output 0–1023
• Operating voltage 3.3–5 V with current consumption below 20 mA
• Threshold logic is handled by the connected microcontroller

Product Description

The moisture sensor measures the water content of soil or water using two fork-shaped contact electrodes. The changing electrical resistance between the contacts is converted by an on-board circuit into an analog voltage value, which is read via the signal pin.

A connected microcontroller records the measured value as a number between 0 and 1023 through its analog input. This value varies depending on the moisture of the material between the contacts; calibration or adjustment is not required. This makes it possible, for example, to detect whether potting soil is drying out or whether a water container has reached a certain fill level.

The 3-pin connection allows direct operation with microcontroller boards using 3.3 V or 5 V logic. Threshold logic for an alarm or switching action when the water content reaches a critical level must be implemented in the controller software, as the module itself only provides an analog output. For long-term stability, it is recommended to briefly dry the contact electrodes after extended measurement series.

Safety Notice

This module is intended exclusively for building prototypes and for testing and development purposes and is not designed for continuous operation in household electrical circuits. Work on or near electrical installations is reserved for qualified electricians. When operating with directly grounded water or in corrosive environments, consult a qualified electrician before commissioning.

Scope of Delivery

• 1x moisture sensor for microcontrollers