How to Use a Relay with a Raspberry Pi

Add an electrically-operated switch to your Pi!
Tyler Tyler (304)
20 minutes

A relay is an electrically-operated switch. These switches can be extremely useful for a variety of Raspberry Pi projects (think turning on a light or opening your garage door. Watch the video below to learn how to drive a relay using your Raspberry Pi.

Raspberry PiRaspberry Pi ×1
SainSmart 2-channel Relay Module ×1

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The following video will show you how to wire up the relay to your Raspberry Pi.

Watch the video:

Here's a copy of the test script used in the video:

#!/usr/bin/env python

import time

import RPi.GPIO as GPIO


GPIO.setmode(GPIO.BCM)
GPIO.setup(17, GPIO.OUT)
GPIO.output(17, GPIO.LOW)

time.sleep(0.25)

GPIO.output(17, GPIO.HIGH)
GPIO.cleanup()

To run the script, simply copy the code above to a file on your Raspberry Pi called test-relay.py (or whatever you want). And then run the script using:

python test-relay.py
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0

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