• HC-SR501
• Pyroelectric IR sensor
• Operating Modes: Repeatable(H), Non-Repeatable(L)
• Range: 7 meters, 120°
• Power Consumption: 65mA
• Operating Temperature: -20~80°C
• Dimensions: 32.2 x 24.3 x 25.4 mm

• 1: Vcc (4.5V-12V)
• 2: Dout (3.3V when motion detected, 0V when idle)
• 3: Ground

Operating Modes

Repeatable(H) mode

In Repeatable(H) mode the output pin Dout will go high (3.3V) when a person is detected within range and goes low after a particular time (time is set by “Off time control” potentiometer). In this mode the output pin will go high irrespective of whether the person is still present inside the range or has left the area.

The sensitivity can be set using the “sensitivity control” potentiometer.

Non-Repeatable(L) mode

In "I" mode, the output pin Dout will go high (3.3V) when a person is detected within range and will stay high as long as they stay within wange of the sensor. Once the person has left the area, the pin will go low after the particular time (which can be set using the potentiometer).

The sensitivity can be set using the “sensitivity control” potentiometer.

AliExpress listing - HC-SR501 HC-SR505 AM312 Adjust IR Pyroelectric Infrared Mini PIR module Motion Sensor Detector Module Bracket For Arduino