iThis 1pcs HC-SR501 Motion Sensor Module is a high-sensitivity IR pyroelectric infrared (PIR) human motion detector, specifically designed for Arduino and Raspberry Pi projects. It utilizes pyroelectric infrared technology to detect the infrared radiation emitted by human bodies and other warm objects, making it an ideal choice for automatic control, security alarm, and smart home projects that require motion detection functionality.
The core of the HC-SR501 module is a high-performance PIR (Passive Infrared) sensor, which can detect the subtle changes in infrared radiation caused by moving warm objects within its detection range. Unlike active sensors, this passive design consumes low power, making it suitable for battery-powered projects such as portable security devices and smart wearables. It has a stable detection performance, with minimal false triggers when properly adjusted.
One of the key features of this module is its adjustable parameters, including detection distance and delay time. The detection distance can be adjusted from 3 meters to 7 meters using the built-in potentiometer, while the delay time (the duration the module maintains a high output after detecting motion) can be adjusted from 5 seconds to 600 seconds. This adjustability allows the module to adapt to different project requirements, whether for short-range detection in a small room or long-range monitoring in an open space.
The HC-SR501 module is fully compatible with Arduino boards (such as Uno, Nano, Mega) and Raspberry Pi, featuring simple wiring and easy integration. It has three pins: VCC, GND, and OUT. The VCC pin supports 5V power supply (compatible with most Arduino and Raspberry Pi power outputs), the GND pin is for ground connection, and the OUT pin outputs a digital signal (high level when motion is detected, low level when no motion is detected), which can be directly read by the controller.
Designed with a compact and durable plastic case, the module effectively protects the internal components from dust and physical damage, ensuring long-term stable operation. It also has a built-in sensitivity adjustment function, allowing users to fine-tune the detection sensitivity to reduce false triggers caused by environmental factors such as sunlight, wind, or small animals.
This PIR motion sensor module is widely used in various applications, including automatic lights, security alarms, smart doorbells, human presence detection systems, and Arduino/Raspberry Pi educational projects. It is easy to program and use, making it suitable for both beginners and experienced enthusiasts. With its adjustable parameters, low power consumption, and wide compatibility, the HC-SR501 IR pyroelectric motion sensor is a reliable and cost-effective solution for adding motion detection capabilities to your electronic projects.