20pcs HCSR505 Mini Infrared PIR Motion Sensor Overview A batch of 20 compact HCSR505 passive infrared motion sensors designed for reliable motion detection in hobby, prototyping, and light commercial applications. Small form factor and simple digital output make these modules easy to integrate into microcontroller and electronic projects. Key benefits Ready for multiple projects: 20 identical modules supplied together to support classroom use, batch installations, or repeated prototyping without repeated ordering. Fast detection and simple integration: Digital output switches when motion is detected, allowing direct connection to microcontrollers, relay modules, or alarm inputs. Space saving design: Miniature size fits into tight enclosures and small devices where larger sensors will not work. Saves development time: Standard 3pin wiring and TTLcompatible output reduce configuration and coding effort. Main features Function: Passive infrared motion detection that senses changes in infrared energy emitted by moving objects. Output: Digital motion output suitable for direct interface with microcontrollers and logic circuits. Power: Operates from low voltage DC. Typical operating range 3.3 to 5 volts. Detection range and angle: Typical detection distance approximately 3 meters with a wide field of view suitable for roomlevel motion sensing. Size and construction: Mini PCB module with integrated Fresnel lens for compact mounting. Lightweight and suitable for surface mounting inside enclosures. Compatibility: Easy to use with common development platforms and controllers including Arduino, Raspberry Pi, ESP32, and similar systems. Low power: Designed for low standby consumption to suit battery powered or lowpower systems. Simple wiring: Standard pinout includes VCC, GND, and OUT for straightforward connections. Practical applications Automatic lighting: Trigger hall, stair, or cabinet lights when motion is detected to improve convenience and reduce manual switching. Security and alarm systems: Use as a motion trigger for entry detection, perimeter monitoring, or device wakeup in alarm projects. Smart home and IoT devices: Integrate into occupancy sensing, energy management, or interactive installations for motionbased control. What you get 20 pieces of HCSR505 mini PIR motion sensor modules, identical specification for consistent performance across installations. Notes for use Mount the sensor behind a nonmetallic opening and avoid direct airflow from vents to prevent false triggers. Allow a short warmup period after power up for stable detection. For extended detection distance or adjustable sensitivity, consider sensor placement and field of view rather than increasing supply voltage. This 20piece pack of HCSR505 modules provides a compact, easy to use solution for multiple motion sensing projects where consistent, repeatable performance and small size are required.