Raspberry Pi Stack Exchange
Raspberry Pi Stack Exchange

Questions tagged [relay]

Electrical device which, when energised by a small electrical current (low-power, control circuit), safely switches a larger electrical current (controlled circuit).

Relays could use an electromagnet to mechanically operate a switch which then also provides complete electrical isolation between control and controlled circuits. Semiconductor-based solid-state relays allow switching without moving parts and are therefore not subject to wear.

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Simple Relay Control

I've got a single relay connected to my RPi but I can't seem to control it. As you can see from the image above: RPi -> Relay 5V -> VCC Ground -> GND GPIO4 -> IN1 Measuring voltage I can successfully verify that I can turn on/high off/low…
Diogo Mendonça
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Wiring a 4 channel relay - is this possible?

After watching many videos and reading, I think I now know how to wire a 4 channel relay to control 4 12V DC Solenoids with my PI. The Solenoids are wired in parallel. Please see picture 1. However, it occurs to me that I could reduce the wiring…
xpug
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Relay stays on when toggling GPIO pin between LOW / HIGH

I've got a small 5v relay board ("Ontengfei" JQC-3FF-S-Z) connected to my Raspberry Pi 3 B+. When I set the GPIO pin mode to OUTPUT, the relay turns on. When I toggle the GPIO pin between HIGH / LOW, the relay just stays on, it doesn't toggle like…
Trevor Sullivan
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Driving 12V relays from Raspberry Pi

I want to use a Raspberry Pi to drive this relay. It is solid state, SP/ST, needs 12V for the coil and can switch up to 16A at 250V AC. Now, I know that The RPi cannot switch natively anything above 3V and I have already found a circuit doing just…
dlyk1988
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Issue with lighting 15w bulb using raspberry pi & 8-pin relay

Being naive to hardware & electronics, I might missing something silly here. Here is my setup to able turn on/off bulb using iOS app and node.js as backend - Successfully setup raspberry pi 2 Integrated 8-pin relay with pi…
BaSha
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First steps into controllers and circuits (NOOB ALERT). Why does relay module works only if connected to 5v pin but not with external 5V source?

As title states, I am taking my first steps into electric circuits and microcontrollers, so I apologize in advance if my question is not clear or does not make much sense. I am trying to control several (3 for now, I am aiming 8) relays modules…
Loris Capria
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4 relay board weird behavior

i'm new to this platform, I hope I'm doing everything right. I bought a 4 relay board some time ago to use it with my pi. When I tested it with the pi, it worked well. After a while I decided to use it in a project. When i connected it to the pi it…
Dj Igiul
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5v relay led comes on and off but relay doesn't switch (no clicking)

channel SunFounder 5V 8 Channel Relay, which stopped working and I'm not sure if because something I did: The first time I connected to my pi everything worked, I powered the board from 5v pin of the pi and all 8 relays nicely clicked and turned…
zura
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Raspberry Pi power on - enable relay

There are loads of Youtube videos on how to control a relay, but I simply want to be able to power up my Pi and let it activate a relay. Then, when I power it down, it should turn the relay off. No buttons or interfaces, just on and off. I've built…
Brenton Meigh
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Relay board and solenoid power source

I am having a bit of an issue with the current setup. Im trying to run multiple solenoid valves of a 16 channel relay optocoupler…
Wayne Irwin
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Web relay switching keyboard shortcut

If I have a relay board controlled from a web interface thru the ethernet port, how can I create a keyboard shortcut to activate the relay without the browser being open?
Simon
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Can Rapberry PI 4 GPIO pins provide a ground instead of 3.3V? Looking to control a 5v relay

new here and to Raspberry PI. I want to use it to be able to toggle a relay, but that relay is a 5v one, and I read that the GPIO pins are only 0-3.3V. Is there a pin that can provide ground when toggled? Can any of the +5V pins be turned on/off?…
idoseadoo
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Relay module at Raspberry Pi zero II wont work as expected

I have connected VCC in 5V pin, GND in gnd pin and IN in GPIO 26 of my Pi. Using simple python code to control the relay import RPi.GPIO as GPIO GPIO.setmode(GPIO.BCM) relay_ch = 26 GPIO.setup(relay_ch, GPIO.OUT) // this switch the relay on (green…
Marcel Kopera
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Safest way for a 220V relay

I need to turn on and off a very power-hungry appliance using my Raspberry Pi. I know a lot about software, and next to nothing about electronics and hardware. I looked around, and I saw a few rather scary things. Is there a 220v plug out there with…
Merc
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Connecting my raspberry pi to latching relay

I am struggling with the same latching relay featured here: Command/control latching relay using gpio pin only Edit: somehow there's been confusion, I'm trying to activate this, the latching relay that's mentioned right in the question linked…
Evan S
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