Product Description

The HR202 Humidity Detection Sensor Module is a compact environmental humidity sensing module designed to detect changes in ambient humidity. It uses a high-quality HR202 humidity sensor along with an LM393 comparator to provide stable and responsive humidity detection.

The module features an adjustable sensitivity/trigger threshold, allowing users to set a desired humidity level using the onboard potentiometer. When the environmental humidity crosses the configured threshold, the module changes its digital output state and provides visual indication through the onboard LED.

The module provides a digital DO output that can be directly connected to a microcontroller such as Arduino, ESP32, or other compatible development boards. It also provides an analog AO output, which can be connected to an ADC input for obtaining a more detailed humidity-related reading.

With its compact design, onboard LEDs, adjustable threshold, and 3 mm mounting holes, the HR202 module is suitable for humidity monitoring, environmental sensing, automatic humidity control, and DIY IoT projects.

Features

• Uses a high-quality HR202 humidity sensor
• Detects changes in ambient humidity
• Adjustable humidity trigger threshold
• Onboard LM393 comparator
• Clean digital comparator output
• Digital DO output
• Analog AO output
• Digital output can interface directly with microcontrollers
• Output driving capability specified as more than 15 mA
• Onboard power indicator LED
• Digital output indication LED
• Adjustable sensitivity using onboard potentiometer
• Compact module design
• 3 mm mounting holes for easy installation
• Suitable for humidity switching and control applications
• Can be used with relay modules for automatic humidity control

Specifications

Note: The supplied product information does not specify an exact operating voltage, humidity measurement range, or humidity accuracy. These values should be confirmed from the specific module version before design calculations or precision measurements.

Working Principle

The HR202 humidity sensor changes its electrical characteristics according to the humidity level of the surrounding environment.

The sensor signal is processed by the onboard LM393 comparator. The potentiometer can be adjusted to set the desired trigger threshold.

When the humidity changes and crosses the selected threshold, the comparator changes the state of the DO digital output. The onboard LED also provides a visual indication of the output condition.

The DO output can be connected directly to a microcontroller’s digital input to detect whether the humidity is above or below the configured threshold.

The AO analog output can be connected to an ADC input to obtain a variable signal related to the sensor condition, allowing more detailed monitoring when used with suitable calibration and software.

Digital Output

The DO (Digital Output) provides a simple HIGH/LOW signal based on the humidity threshold configured using the onboard potentiometer.

It can be connected to:

• Arduino
• ESP32
• ESP8266
• Raspberry Pi through suitable interfacing
• Other compatible microcontrollers

This makes it useful for applications where the requirement is simply to detect whether humidity has crossed a selected level.

Analog Output

The AO (Analog Output) provides an analog signal that can be read using a suitable ADC.

This allows the module to be used for applications requiring more than simple threshold detection. The analog reading should be calibrated against the actual humidity conditions if accurate humidity measurement is required.

Adjustable Humidity Threshold

The onboard potentiometer allows the user to adjust the trigger threshold according to the application.

For example, a user may configure the module around a desired humidity condition and use the digital output to activate another circuit when the humidity crosses that threshold.

The exact humidity percentage corresponding to a particular potentiometer position depends on the sensor, module characteristics, environment, and calibration.

LED Indicators

The module includes onboard LEDs for easy status monitoring:

• Power LED: Indicates that the module is powered.
• Digital Output LED: Indicates the current digital output condition.

These indicators make it easier to test and troubleshoot the module during development.

Applications

The HR202 Humidity Detection Sensor Module can be used for:

• Ambient humidity detection
• Humidity threshold monitoring
• Automatic humidity control
• Greenhouse monitoring
• Plant and agricultural projects
• Smart home systems
• Environmental monitoring
• Humidity alarms
• DIY IoT projects
• Arduino humidity projects
• ESP32 humidity projects
• Relay-based humidity control
• HVAC-related prototypes
• Equipment protection
• Educational electronics projects

Package Includes

• 1 × HR202 Humidity Detection Sensor Module

Product Disclaimer

• This module is intended primarily for humidity detection and threshold-based control.
• The exact humidity percentage cannot be determined solely from the potentiometer position without appropriate calibration.
• The supplied product information does not provide a guaranteed humidity accuracy specification.
• The module’s exact operating voltage is not specified in the supplied information and should be verified for the specific module before connection.
• The analog output should be calibrated if used for quantitative humidity measurement.
• Do not connect the module directly to loads that exceed the specified output capability. Use an appropriate transistor, MOSFET, or relay interface for higher-current loads.
• Product appearance and component placement may vary slightly between production batches.

Note: The product images are for illustration and representation purposes only. The actual product may slightly differ in appearance, colour, design, or component placement from the images shown due to manufacturing variations and production batches.