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).
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33 views
3.3v Relay switches on/off/on - off fails 2nd switch off
This 3.3v .relay, link to the the >>> Datasheet
As the title mentions works fine until I try to switch it off the second time round,
I see the red LED turning on (it looks a touch dim)
...
0
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2answers
45 views
5V Relay only works if VCC is 3.3V
I am very new to all of this, so please excuse if this is a very basic question.
I am trying to power a tiny water pump with my raspberry pi. For that I need the 3.3V or 5V output, because the GPIO ...
0
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2answers
43 views
RPi 3 B+, set defaults for GPIO pins on boot and shutdown
I am using Raspberry Pi 3 B+ with
Linux raspberrypi 5.4.83-v7+ #1379 SMP Mon Dec 14 13:08:57 GMT 2020 armv7l GNU/Linux
to control a set of relays. I set:
gpio mode 7 output
gpio mode 0 output
gpio ...
1
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2answers
60 views
Using Relays to Power off then Cut power to Pi Zero
I have a raspberry pi zero that I am running off a battery for remote logging reasons.
There is a low battery shut off module I have connected to the battery in case the battery gets below a certain ...
1
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2answers
90 views
How to detect if an external Relay is ON or OFF
I want to know the state of an external Relay connected to my Raspberry-Pi. Basically if there is current flow or not in A-B. A-B should be connected to R-Pi.
I am not sure how to proceed even though ...
0
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2answers
32 views
How to drive two 3v relays safely from Raspberry PI?
I use PI 4 to power two 3v relays. One is controlling 5v dc, another 12v dc. And about once a minute I am switching each relay signal state to On/Off
So each relay is connected to 3v pin, ground pin ...
0
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1answer
66 views
Using GPIO to control 5v relay module not working
so this is my first time trying to use a Raspberry pi and I wanted to automate a motor using a 5v relay module. I'm using a Raspberry Pi Zero W. I am using a 5v 2amp power supply to power the ...
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4answers
360 views
Using single 5V relay module (jqc-3ff-s-z) - Asking for help
I have a developer background missing the electronics background. I read some threads with great interest:
Using single 5V relay (jqc-3ff-s-z) - safety advice required
and
5V relay (jqc-3ff-s-z)
I ...
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0answers
28 views
Protecting Raspberry Pi from EMI generated from VFD
I built a PCB to control a couple of Industrial contactors and an VFD.
The GPIO are categorized, inputs and outputs.
The output gpio are connected to the relay system.
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43 views
Raspberry PI and 8 module relay board
I have a raspberry pi 2 and an 8 module relay board (http://nettop.gr/index.php/en/hlektronika/relay/8-channel-5v-relay-module-with-light-coupling-5v.html).
Between the relay board and the raspberry I ...
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1answer
36 views
DockerPi relay is wired backwards from others?
First off, apologies if I should have posted this elsewhere (such as under general electronics, etc.)
I have two relays (JBTek, DockerPi relay hat) I have been experimenting with to control input ...
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2answers
199 views
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0answers
66 views
Wiring 12V 5 pin relay (without a module/board) for usage with Raspberry Pi
I'm trying to setup an automated garden as a quarantine project for my mother and I can't really figure out how to properly wire a 12V 5-pin relay module as every tutorial online only shows the ones ...
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0answers
131 views
relay switch switches ON but never switches OFF [closed]
I connected my FL-3FF-S-Z two channel relay board to my Raspberry Pi 3, with gpio 0 and gpio 1 (numbers are from to $ gpio readall).
Following some guide, as GPIO generates only 3.3v I have removed ...
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1answer
174 views
Relay Active HIGH
I am building an irrigation system, and to make it short, I need to decouple the electric-valve to the Raspberry.
I am so using the following relay.
It works fine, but it is active LOW, for my use ...
0
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1answer
126 views
5V Relay module working but LED not turning on - How to wire? [closed]
I'm trying to control a relay from Raspberry Pi that will switch an LED on/off.
The relay is working (lightning up and clicking), but the LED doesn't turn on.
Here is how I wired everything:
VCC - 5V
...
0
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1answer
38 views
Raspberry Pi - Activate relay by phone [closed]
I'd like to set up a system to control a relay via land line. My goal is to somehow run a landline to the Raspberry Pi unit and have it trip a relay when the number is called and a DTMF sequence is ...
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1answer
26 views
using 2 pins to power the same relay
I have relay that requires 20mA to operate, which is a bit more than the pi can give from one pin. I as wondering if t was safe to connect 2 GPIO pins together to power the relay. I would use a diode ...
0
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2answers
166 views
How I can control an AC 220v with a relay and a Raspberry Pi 3B [closed]
I'm a newbie in this topics. I love electronics and I love the power of the boards like Raspberry Pi and I want to learn to use it by myself learning in internet, but I have a lot of lacks of ...
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2answers
83 views
Problems with the rpi zero and relay [closed]
I Have a problem...
(above the relay-coil Datasheet)
I want to control a single relay with my pi zero, but it seems that it doesn't have enough power.
the 3.3V pin of the rpi (measured to 3.19V) works ...
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2answers
396 views
How to turn off relay when RPi shuts down
I have connected a relay to BCM 14 and by setting its output to HIGH I can turn it on, making a 220V bulb to turn on.
I use for that the following python instructions:
GPIO.setmode(GPIO.BCM)
GPIO....
0
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3answers
282 views
How can Rpi python control a 5V relay module, opto-isolated, with a JDVcc jumper? [closed]
Just starting to explore python, Raspberry and a relay. I want to control my 2-channel relay with a button. This is my test code:
import RPi.GPIO as GPIO
import time
import requests
from datetime ...
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0answers
35 views
Relay is behaving differently from tutorial
Given:
Raspberry Pi3
Sunfounder 2 channel relay
plugged into 3.3v
plugged into ground
plugged into pin 18
import RPi.GPIO as GPIO
import time
GPIO.setmode(GPIO.BCM)
GPIO.setup(18, GPIO.OUT)
GPIO....
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0answers
128 views
GPIO Power off on shutdown with retropie
i asked this question before but i have added a diagram to explain it more clearly.
I am building a retropie arcade machine with a raspberry pi. I have added a shutdown / startup button to shutdown ...
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0answers
131 views
How to cut power to gpio pins on shutdown
I am working on a project where i am using a pi running retropie to make a homemade arcade machine. i have wired and coded a startup/shutdown button. i would like to set up the pi n such a way i can ...
1
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1answer
125 views
Running pump & servo - Relay needed?
simulate this circuit – Schematic created using CircuitLab
So I am working on a project that will require both a servo motor plus a small water pump.
Both run on 3.7 -6v and I am going to use ...
0
votes
1answer
55 views
no output from 8 channel relay when i run the python script below
# import GPIO and datetime
import RPi.GPIO as GPIO
import datetime
# set GPIO numbering mode and define output pins
GPIO.setmode(GPIO.BOARD)
GPIO.setwarnings(False)
GPIO.setup(37,GPIO.OUT) #Relay 1
...
1
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0answers
333 views
RPi.GPIO + single channel relay + solenoid lock
I'm working on my first python/hardware project and I want to create a simple (or at least I thought it was simple) cabinet lock, which will lock/unlock when certain RFID tags are approached to the ...
2
votes
4answers
95 views
Why is my relay switching on automatically when I start my program?
I'm building a little automated hydroponics system using a raspberry pi zero, a 5 volt relay, a pump and a soil moisture sensor from adafruit. So far everything is working, I can pull the pin to high ...
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1answer
139 views
Process to select and stack a relay HAT and a touch-display HAT
The goal is to design thermostat system via stacking Raspberry pi HATs:
Raspberry pi (3B+ or 4)
4-channel relay
TFT Touch Display
It would be preferable that community experience point out any ...
2
votes
1answer
172 views
Relay does not turn off
I am trying to control a 4-Relay module with my Raspberry Pi 4.
I tried to do that by writing this script:
import RPi.GPIO as GPIO
import time
GPIO.setmode(GPIO.BOARD)
relais_1 = 8
relais_2 = 10
...
1
vote
2answers
179 views
Use HC-SR04 Distance Sensor and Relay to trigger the Water Pump - Need help with triggering the pump
I am trying to trigger/stop a water pump with the use of a 4-channel relay and a UC-SR04 distance sensor.
I tried with some codes but I think I am missing something because although there was no error ...
1
vote
2answers
250 views
Multi-threading python function using list and dictionary of GPIO pins cannot activate a relay problem
At the first part of the code(Initializing relays) the GPIO output works as expected, but at the second part it doesn't works, I have break my head for the last four hours trying to find out what is ...
1
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1answer
152 views
How to make a system that uses a mobile sim and that acts on a relay by ringing the sim
I want to create a system that has an internet connection via a mobile sim and allows owners of enabled telephone numbers to switch a relay by ringing the device sim.
The system must be able to ...
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0answers
381 views
Rpi3 Home Assistant To Read Signals at GPIO Pins Problem
I'm really new to Raspberry Pi, so please forgive me if this is a noobish question.
I have a very simple setup: Raspberry Pi 3 running Home Assistant with a switch connected to GPIO12 and 3.3v.
The ...
4
votes
4answers
215 views
gpio turning on/off relay, seems backwards
I have a Raspberry Pi 3b and wired to a 4 port relay I got from Amazon:
https://www.amazon.com/JBtek-Channel-Module-Arduino-Raspberry/dp/B00KTEN3TM/
Everything is working, but it seems backwards to ...
0
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0answers
29 views
Powering solenoid from batterypack
Im trying to power my 6V solenoid that is connected to my 8 channel 5V relay using my 8 x AA batterypack. The pi is being powered through an adapter and the relay from the VCC to 5V pi. When the LED ...
2
votes
2answers
899 views
how do I automatically power off the raspberry pi and cut power every night and then power it back on each day?
Background
I'm a student working on research project to develop a remote wireless sensor network of data loggers. Each data logger (aka node) is going to be retrofitted to a bird feeder that reads ...
0
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0answers
123 views
using Pi Zero W GPIO relay control
I am trying to control my relay with Raspberry GPIO.
Using the terminal to write to gpio5 (Physical 18, BCM 24) works:
gpio mode 5 out
gpio write 5 1
Trying to do the same in my c++ code doesn't ...
2
votes
1answer
150 views
12V Solenoid with Relay doesnt trigger
So I am using 8 AA 1.5V batteries that is wired to my 12V 16 channel relay which is wired to my Rpi.
I want to be able to control 16 solenoids and use the relay as a switch for the solenoids. As far ...
1
vote
2answers
76 views
Relay modules: Can I switch AC in one and DC in another?
I would like to control both 120VAC and 24VDC from my RPi 3B+. To make this easy, I'm looking at one of the various 3ch or 4ch relay modules for an RPi 3B+, like this or this. I'm familiar with using ...
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0answers
238 views
External power supply to a relay controlled by a Raspberry Pi
I am a beginner to relays and Raspberry Pi so please pardon me if my question sounds naive. I am trying to control 4 DC motors using relays and raspberry pi. I have decided to use an external supply ...
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1answer
216 views
I think I fried my Raspberry Pi, but I'm not sure
I was making connections from my Raspberry Pi to a relay module. While I was running some sample code, I noticed that after I had terminated the program I was still getting a high CPU usage (around 60%...
3
votes
2answers
3k views
Rpi GPIO Controlling 5V Relay Problem
I am working on a project that requires a camera analyzing some images and activating the appropriate GPIOs to control a relay board. I currently have a touchscreen display, a Raspberry Pi Cam ...
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3answers
1k views
Rpi UART control IR Remote HDMI switch problem
I've been reading about how to use the GPIO to toggle a button on a thing I've taken apart.
It's like this: Amazon
I watched a video of a guy using an opto-coupler, what are the basics here? I'm ...
1
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3answers
78 views
Voltage dropped significantly on GPIO 4 with a relay coil
I have a Raspberry PI 3 B+, and when I activate the GPIO 4 as output and checking agains a multimeter I get its 3.3V as expected.
If I connect the GPIO4 to one end of a coil (http://www....
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2answers
1k views
Driving 12V/24v Relay from raspberry pi
I am trying to drive the 12V/24V relay using Rasberry pi 3. I have got schematic from one of the forum.I have question related to below schmatic.
1) The ckt build to drive 5V relay . How can use ...
0
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2answers
173 views
Is 5V out on the Pi Zero W unregulated?
I want to power a 5V relay breakout board from a Pi Zero W. I believe the 5V pads are "raw" and a "pass through" voltage? Is this correct?
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4answers
2k views
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,...
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1answer
343 views
Is a RC snubber required when using the pi with a relay?
I am hoping to use raspberry pi to switch on and off a heating lamp and an aquarium pump via a relay switch. Both devices are plugged into 120V AC normally.
The relay tutorials online seem to be ...
