PIR Motion Sensor Hookup Guide

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Contributors: jimblom
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Introduction

Passive infrared (PIR) sensors are motion-detecting devices used in security systems across the world -- even though you may not see them, they probably see you!

PIR Motion Sensor (JST)

PIR Motion Sensor (JST)

SEN-13285
$9.95
19

Using the PIR sensor is simple: power it up, connect a pull-up resistor to the open-collector signal pin, and watch for it to go low. The PIR can sense abrupt changes in scenery as far as 10 feet (~3m) away. Once your microcontroller is sensing movement, it can trigger a buzzer, text message, tweet, or a klaxon.

Suggested Materials

This tutorial serves as a quick primer on PIR motion sensor and demonstrates how to hook them up and use them. Beyond the sensor itself, the following materials are recommended:

Arduino Uno -- We'll be using a digital pin on the Arduino to read the state of the PIR sensor's signal output. Any Arduino-compatible development platform -- be it a RedBoard, Pro or Pro Mini -- can substitute.

Jumper Wires -- The PIR sensor is terminated with a 3-pin JST cable one of the easier ways to connect this to an Arduino is to plug a few jumper cables into the connector and run them straight to an Arduino.

Jumper Wires Standard 7" M/M - 30 AWG (30 Pack)

Jumper Wires Standard 7" M/M - 30 AWG (30 Pack)

PRT-11026
$2.25
20
Mini Speaker - PC Mount 12mm 2.048kHz

Mini Speaker - PC Mount 12mm 2.048kHz

COM-07950
$1.95
5
LED Mixed Bag - 10mm

LED Mixed Bag - 10mm

COM-13326
$9.95
3

SparkFun RedBoard - Programmed with Arduino

DEV-12757
127 Retired

Beyond those two items, you may want to add a buzzer or large LED to make range testing of the PIR sensor more convenient.

Suggested Reading

PIR sensors are a great entry-level component for beginners, but there are still a few basic electronics concepts you should be familiar with. If any of these tutorial titles sound foreign to you, consider skimming through that content first.

Pull-up Resistors

A quick introduction to pull-up resistors - whey they're important, and how/when to use them.

Light

Light is a useful tool for the electrical engineer. Understanding how light relates to electronics is a fundamental skill for many projects.

What is an Arduino?

What is this 'Arduino' thing anyway?

Resistors

A tutorial on all things resistors. What is a resistor, how do they behave in parallel/series, decoding the resistor color codes, and resistor applications.