PIR Motion Detector Sensor Module – HC-SR501
This passive infrared (PIR) module detects changes in infrared radiation associated with movement. It includes a pyroelectric sensor, Fresnel lens, conditioning circuitry, and adjustment potentiometers for sensitivity and delay time.
Supplier-listed features
Model: HC-SR501
Dual-element, low-noise, high-sensitivity infrared sensor
Default blockade time: approximately 2.5 seconds
Adjustable sensitivity; supplier describes approximately 3–7 m detection range depending on adjustment
Adjustable output hold time; supplier describes approximately 5–200 seconds depending on adjustment
Applications
Motion-triggered lighting prototypes
Intruder-alarm demonstrations
Arduino, Raspberry Pi and microcontroller projects
Allow the module to stabilize after power-up and test its output in the intended environment. Actual range and timing depend on settings and environmental conditions.