HCSR501 PIR Motion Sensor Module Key benefits Reliable motion detection for automatic control of lights and devices. Wide input voltage and very low standby current make it easy to integrate into battery or mains projects. Adjustable sensitivity and delay let you tailor detection distance and run time to each installation. Small board size and standard pinout simplify mounting and wiring in enclosures or on prototypes. Main features Sensor type: PIR motion detector module (HCSR501 type). Operating voltage: DC 4.5 to 20 V. Quiescent current: under 50 uA. Trigger modes: two options via trigger pin. Low selects nonrepeatable trigger mode. selects repeatable trigger mode. Default is repeatable trigger. Delay time: adjustable. Default range 5 to 18 seconds. Module supports a broader range from about 0.1 second up to tens of seconds, and the delay trimmer can extend the delay up to about 5 minutes when set fully clockwise. Minimum practical delay with the trimmer set fully counterclockwise is about 3 seconds. Block time: default 2.5 seconds. Adjustable across a range from about 0.1 second to tens of seconds. Detection angle: approximately a 100 degree cone. Detection range: adjustable. Turning sensitivity control clockwise decreases detection range; full clockwise gives about 3 meters. Turning it counterclockwise increases range; full counterclockwise gives about 7 meters. Lens diameter: 23 mm. Board dimensions: 32 mm by 24 mm. Why customers need this sensor Automates lighting and equipment to save energy and reduce manual switching in corridors, storage areas, and utility spaces. Provides a simple motion input for home automation, security systems, and custom electronics projects. Compact and low power makes it suitable for battery operated devices or installations with limited space. Compatibility and performance Works with a wide range of loads when used with appropriate driving circuits or relays, including incandescent and fluorescent lamps, buzzers, automatic doors, electric fans, washing machines and dryers, and other control systems. Offers stable performance across the specified voltage range and maintains very low standby power draw. Installation and adjustment tips Sensitivity adjustment: turn the sensitivity potentiometer clockwise to decrease range and counterclockwise to increase range. Use full clockwise for about 3 meters and full counterclockwise for about 7 meters as reference points. Delay adjustment: turn the delay potentiometer clockwise to increase the output hold time and counterclockwise to shorten it. Fully clockwise can deliver up to about 5 minutes; fully counterclockwise reduces delay to around 3 seconds in typical setups. Choose trigger mode according to application needs: nonrepeatable trigger mode starts the delay on first detection and ignores further motion until the delay ends; repeatable mode restarts the delay each time motion is detected during the active period. Typical use scenarios Corridor or stairway lighting: automatically switch corridor lights on when motion is detected and turn them off after a set delay. Retail or office entrance automation: trigger automatic doors or alert systems when a person approaches. Appliance or equipment control: start ventilation fans, laundry machines, or buzzers only when motion is present to reduce runtime. Physical and integration notes Small 32 mm by 24 mm PCB fits easily into enclosures or mounts behind fixtures. Standard sensor diameter and mounting allow straightforward replacement or integration with existing PIR lens holders. Requires appropriate interfacing or relay driver for mains powered loads; observe standard electrical safety practices when connecting voltage devices. This HCSR501 PIR sensor module provides a compact, adjustable, and low power solution for adding motion detection to lighting, security, and automation projects.