HC-SR501 PIR Motion Sensor Module (SMD Version) – Adjustable Passive Infrared Human Body Detector

Product Description

Automate your environment with the HC-SR501 PIR Motion Sensor Module. This industry-standard Passive Infrared (PIR) detector is designed to sense human or animal movement by measuring changes in infrared radiation levels. At Robogears, we recommend this SMD version for its enhanced stability and compact component profile, making it easier to integrate into slim enclosures. The module features two on-board potentiometers to fine-tune sensitivity and delay time, along with a specialized Fresnel lens to maximize its 120-degree detection cone. Whether you are building an energy-saving light controller or an intruder alert system at your Pimpri workshop, the HC-SR501 provides reliable, low-power motion detection with a simple 3-pin interface.

Detailed Key Features

• Passive Infrared Technology: Detects body heat movement without emitting any radiation, ensuring completely silent and safe operation.

• Dual Adjustment Controls: Features two multi-turn potentiometers: one for Sensitivity (distance) and one for Time Delay (how long the output stays HIGH).

• Wide Voltage Compatibility: Operates on anything from 4.5V to 20V, though the digital output signal is a safe 3.3V, making it directly compatible with Arduino and Raspberry Pi.

• Repeatable Trigger (H Mode): When set to 'H', the sensor will keep the output HIGH as long as motion is continuously detected, preventing lights from turning off while someone is in the room.

• Low Power Consumption: Drawing less than 50µA in standby, it is perfectly suited for battery-powered IoT security nodes.

All Technical Details

• Pin Definition:

  • VCC: Positive Power (5V is standard for Arduino).

  • OUT: Digital Output (3.3V High when motion is detected).

  • GND: Common Ground.

• Temperature Compensation: The SMD internal circuitry helps maintain sensing accuracy even during ambient temperature fluctuations.

• Lens System: High-quality polyethylene Fresnel lens splits the sensing area into multiple zones for better motion resolution.

• Applications: Automatic hallway lighting, security alarms, interactive museum exhibits, and "human-present" industrial safety triggers.