HC-SR501 PIR Motion Detector Sensor Module for Arduino & Raspberry Pi

Specifications:

• Operating Voltage: 4.5V to 20V DC
• Static Current: < 50µA
• Logic Output Level: High 3.3V / Low 0V
• Delay Time: Adjustable from 0.5 seconds to 200 seconds via onboard potentiometer
• Block Time: 2.5 seconds (default)
• Sensing Range: Adjustable up to 7 meters (110° cone angle) via onboard potentiometer
• Trigger Modes: L (non-repeatable trigger) / H (repeatable trigger) via onboard jumper selection
• Dimensions: 32mm × 24mm × 25mm
• Operating Temperature Range: -15°C to +70°C
• Compatible Platforms: Arduino Uno, ESP32, Raspberry Pi, STM32, and standard digital logic circuits

Unlock New Capabilities

Past Projects 
If you've already experimented with basic digital inputs like reading a tactile pushbutton switch or capturing data from a basic infrared obstacle sensor, you already understand how a microcontroller processes high and low binary logic states. This means you possess the absolute foundation needed to move from short-range line-of-sight tracking to wide-angle volumetric thermal presence detection.

Feature Upgrade 
This HC-SR501 PIR sensor unlocks automatic hands-free room lighting relays, smart burglar alarms, non-contact visitor counter logs, and power-saving sleep-state triggers for nearby media displays. By sensing real-time shifts in ambient blackbody infrared radiation, you can construct background environmental triggers that respond directly to human presence across an entire room—a scale impossible to monitor with simple proximity switches.

Effort Level & Minimum Hardware

• Arduino Uno or alternative development platform — essential to monitor the digital output transitions and initiate secondary responses like firing a buzzer or relay.
• USB interface cable — provides a clean 5V tether from your terminal to run the microcontroller and serves as the data link for uploading your threshold code.
• 3× Jumper wires (Female-to-Male) — mandatory to hook up the sensor's sub-lens header pins directly into the microcontroller input ports.
• Solderless prototyping board — recommended to anchor connections and distribute power buses safely without running risks of short-circuits.

Virtual Technician & Wiring Guide

• Warm-Up Phase Lock: Upon receiving initial power, the HC-SR501 requires an initialization window of 30 to 60 seconds to calibrate its internal pyroelectric element against ambient thermal baselines. Expect erratic or stuck-HIGH logic states on the output pin during this warm-up interval.
• Power Supply Minimums: Always supply at least 4.5V to 20V DC to the VCC pin. Even though the module outputs a friendly 3.3V logic signal, attempting to run the main power rail directly from a 3.3V pin will starve the onboard BISS0001 controller chip and result in dead sensor loops.
• High-Voltage Isolations: If using this motion tracker to automate commercial 230V AC household appliances, never wire mains lines anywhere near this sensor board. Always isolate high-voltage paths through an optocoupled electromagnetic or solid-state relay module.

Pin mapping  

Package Includes:

1 x HC-SR501 PIR Motion Detector Sensor Module for Arduino & Raspberry Pi

Frequently Asked Questions

1. Is the HC-SR501 PIR Motion Sensor compatible with Arduino Uno?
   Yes, this motion sensor module is fully compatible with the Arduino Uno because it can be powered directly from the board's 5V pin and its 3.3V logic output is safely registered as a high signal by any digital input pin.
2. Can I use the HC-SR501 PIR Motion Sensor with an ESP32 board?
   Yes, it is fully compatible with the ESP32. While the module requires 5V to power its internal regulator circuitry, its logic output line emits a safe 3.3V high state that will not damage sensitive ESP32 GPIO pins.
3. Can I run the HC-SR501 PIR Motion Sensor on a Raspberry Pi using MicroPython?
   Yes, you can read the digital high and low states of the sensor module directly within MicroPython on a Raspberry Pi Pico or standard Raspberry Pi board using the native machine.Pin input framework.
4. Can I place multiple HC-SR501 PIR Motion Sensors on the same microcontroller system?
   Yes, you can wire multiple motion sensors to a single board simultaneously by assigning the output signal line of each individual breakout module to a unique digital GPIO pin.
5. What supply voltage does the HC-SR501 PIR Motion Sensor require to function?
   The sensor module handles a wide input supply range spanning from 4.5V to 20V DC, allowing it to easily adapt to standard 5V rails or raw external battery banks.
6. Can I power the HC-SR501 PIR Motion Sensor directly from a 3.3V power pin?
   No, you cannot run this sensor off a 3.3V rail. The onboard voltage regulator needs a minimum input threshold of 4.5V to stabilize power across the BISS0001 IC and avoid circuit death loops.
7. How much operating current does the HC-SR501 PIR Motion Sensor consume?
   The module is highly energy-efficient, drawing a minimal static idle current of under 50µA, making it ideal for low-power battery-operated monitoring systems.
8. How do I hook up the HC-SR501 PIR Motion Sensor to my Arduino Uno board?
   Route the sensor's VCC pin to the Arduino 5V line, attach the GND pin to a common system ground, and connect the middle OUT pin to Digital Pin 2 for quick signal processing.
9. Which pins should I use to connect the HC-SR501 PIR Motion Sensor to a Raspberry Pi?
   Connect the sensor's VCC pin to a physical 5V pin (Pin 2 or 4), wire GND to a physical GND terminal (such as Pin 6), and attach the OUT pin to any open GPIO header like GPIO17.
10. Do I need to use an external resistor or logic level shifter with the HC-SR501 PIR Motion Sensor?
    No shifter is required because the module natively puts out a 3.3V high logic signal, which is universally safe and fully readable by both 5V systems and 3.3V microcontrollers.
11. Which specific Arduino library do I need to download for the HC-SR501 PIR Motion Sensor?
    No dedicated library is required to operate this component. It functions via a simple binary trigger state that is captured effortlessly using the native digitalRead() command.
12. Is there a specialized MicroPython library file for running the HC-SR501 PIR Motion Sensor?
    No custom external driver files are necessary since the board interfaces via straightforward digital logic, which is supported out-of-the-box by the core machine python modules.
13. Where can I find basic example code to test my new HC-SR501 PIR Motion Sensor?
    You can find starter sketches directly on the Arduino Forum or by opening the built-in "DigitalInputPullup" example located inside the standard Arduino IDE software suite.
14. Why is my HC-SR501 PIR Motion Sensor constantly outputting a high signal value of 1?
    A stuck-HIGH output state usually occurs because the sensor is still in its 60-second initialization window, or your time delay potentiometer is tuned to its absolute maximum setting of 200 seconds.
15. Why are the motion readings from my HC-SR501 PIR Motion Sensor inconsistent or jumping randomly?
    Erratic signal response is typically caused by power supply ripple noise or a missing common ground link. Ensure that a solid ground wire securely joins the sensor directly back to the microcontroller's GND node.
16. Why is my microcontroller failing to detect any response from the HC-SR501 PIR Motion Sensor?
    Detection failures are almost always traced back to loose wire terminations or cold solder connections along the pin headers. Verify lines using a digital multimeter set to continuity mode.
17. My HC-SR501 PIR Motion Sensor triggers correctly at times but fails during rapid movements — how do I fix this?
    This issue is caused by the default 2.5-second internal block time locking out triggers. Adjust the onboard trigger mode jumper from single-trigger mode (L) to repeatable-trigger mode (H) to resolve this restriction.
18. Does Probots provide bulk sourcing quantities of the HC-SR501 PIR Motion Sensor for commercial projects?
    Yes, our Bangalore engineering and logistics team handles corporate inventory logistics and bulk institutional quotes. Contact our sales department through the enterprise channel for volume processing.
19. Is the HC-SR501 PIR Motion Sensor distributed by Probots a verified genuine part?
    Yes, every sensor module we supply is sourced through vetted Tier-1 factory lines to ensure proper BISS0001 silicon quality, protecting your builds from the flawed rejects prevalent across unverified channels.
20. Does Probots offer post-purchase hardware support for the HC-SR501 PIR Motion Sensor?
    Yes, all hardware purchases include access to our localized Bangalore technical helpdesk, where field engineers are ready to assist with wiring diagnostics, pin configurations, and troubleshooting.