HC-SR501 PIR Motion Detection Sensor Module

The HC-SR501 is a Passive Infrared (PIR) motion sensor module widely used in automation and security projects to detect the movement of humans or animals. It works by measuring changes in infrared radiation levels within its field of view. When motion is detected, the sensor's output pin sends a HIGH (3.3V) digital signal, making it incredibly easy to interface with microcontrollers like Arduino, Raspberry Pi, or ESP32.

Here are the key technical specifications of the HC-SR501 module:

• Operating Voltage: 4.5V to 20V DC (typically powered via 5V)

• Output Signal: 3.3V TTL logic (HIGH when motion detected, LOW when idle)

• Current Drain: < 60 µA (extremely low power consumption)

• Detection Range: Adjustable from 3 meters to 7 meters

• Detection Angle: Up to 120 - 140 degrees

• Delay Time: Adjustable from ~3 seconds to 300 seconds (5 minutes)

• Blockade Time: ~2.5 seconds (the sensor ignores motion briefly after the output goes LOW)

• Trigger Modes: Repeatable (H) and Non-Repeatable (L), configurable via an onboard jumper.