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).
215
questions
1
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1answer
21 views
Need script to make scheduled 8 channel relay outputs [closed]
This script fires my relays, but I don't know how to change duration and need it to fire daily to run pump and ozonator for an iso float tank. I'm currently only using GPIO 9 and 10
#!/usr/bin/python
...
1
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3answers
61 views
12v 4 channel relay pinout and explanation
I am kind of dipping my toe in this lake. Not a hardware/electronics person, more of a software guy (programmer). I am not able to easily find information about the 12V 4 Channel Relay (duinotech).
I ...
0
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2answers
120 views
Raspberry Pi , RFID , Relay Module and Magnetic Door
I have used the code from github and in that code i am implementing the raspberry pi and the RFID and relay module with magnetic door unlock. Everything is working Okay , the RFID , the Relay module ...
0
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1answer
42 views
How to control raspberry pi 4 GPIO pins by running android application in the rpi and in mobile?
I am trying to build a project based on IoT. My goal is to trigger relays connected to GPIO pins in rpi4 by using an android application running in rpi4 itself which can be accessed with an official ...
0
votes
1answer
51 views
Use Pi to control power to usb-connected device
I have a digital microscope connected to my pi (usb) that you can use in a browser with a java web app that I have written. The microscope is also powered through the usb. There is no on or off switch,...
0
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2answers
34 views
Do I need additional protection when using a 5V relay module with the raspberry Pi?
Noob here, I have purchased a relay module (see pic below), and was wondering if I needed to add any other protection components to the Pi. Through my limited research, I found that using a diode, ...
0
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0answers
35 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
108 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
46 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
vote
2answers
98 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
vote
2answers
101 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
34 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
votes
1answer
103 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 ...
1
vote
4answers
621 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 ...
0
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0answers
32 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.
0
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0answers
46 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 ...
0
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1answer
39 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 ...
1
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1answer
485 views
2
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0answers
68 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 ...
1
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0answers
194 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 ...
0
votes
1answer
229 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
votes
1answer
213 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
votes
1answer
44 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 ...
0
votes
1answer
30 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
226 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 ...
-1
votes
2answers
142 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 ...
1
vote
2answers
506 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
votes
3answers
366 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 ...
0
votes
0answers
36 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....
0
votes
0answers
149 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 ...
1
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0answers
164 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
165 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
63 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
477 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
97 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 ...
1
vote
1answer
154 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
178 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
231 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
287 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
vote
1answer
180 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 ...
0
votes
0answers
454 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
234 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
votes
0answers
30 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
1k 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
votes
0answers
142 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
156 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
81 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 ...
1
vote
0answers
275 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 ...
1
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1answer
243 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 ...
