A relay generally has 3 connection points on the controlled circuit side, Normally Open (NO), Normally Closed (NC) and a … I connected the 5v output to the VCC pin, the ground to ground and a GPIO pin to the IN pin on the relay. Ethernet cable or WiFi dongle 5. Step 1 : Controlling switches with Python. gpio python raspberry pi relay; Search Forums; New Posts; W. Thread Starter. Thanks . Comes with development resources, including examples in wiringPi, WebioPi, shell, python, and bcm2835; What's on the RPi Relay Board. Am I on the right track? On the Raspberry Pi's pins: Now you can turn your Raspberry Pi on, and we'll begin the code. In this tutorial we are going to go over soldering the header to the Relay HAT, use Python with the included Pi.GPIO library to write code that triggers each relay, and go over the external relay connections and configuration options on the board. Rob. Here is an image of the GPIO pins on the Raspberry Pi: First, I started out by hooking up the relay to the Raspberry Pi like so: The red wire (female to female) leads from the JD_VCC pin on the relay board to the 5V pin (pin 2) on the Raspberry Pi. Could I use something like the import time feature and set the sleep.time(duration) as the on time and then turn off once the duration time is met? ... PINOUT connections for the Raspberry PI. Next, create a new python file, and let's begin: import RPi.GPIO as GPIO import time GPIO.setmode(GPIO.BCM) Power Supply 4. Relay RPI. Pluggable connectors make the 8-RELAYS card easy to use when multiple cards are stacked up. It’ll limit the drain to 2.5mA on that part of the circuit. Since the Raspberry Pi's GPIO pins output 3.3v I used a set of transistors to take the relay pins to ground. ... perhaps I should have provided more information. When this jumper is connected, the relay can be controlled by the Raspberry Pi. i successfully connected but i really need a simple code to run it to trun on and off the A bulb. This post describe how to install a 4 channel Relay board on a Raspberry Pi and how to control it with Domoticz. I used that transistor but it seems not to work. Jumper wires You can use the preceding links or go directly to MakerAdvisor.com/toolsto find all the parts for your projects at the best price! I have Raspberry Pi B+ and i just bought 8 channel relay. However, since the relay boards operate at 5v, another resistor between the IN pin on the relay board and GPIO on the Pi is recommended. Perfect add-on to your project when you have to control large number of loads. On the Raspberry Pi's pins: Now you can turn your Raspberry Pi on, and we'll begin the code. I’m also using an old DOS program (created in VisualBasic for DOS). VCC 5v. eval(ez_write_tag([[728,90],'tutorials_raspberrypi_com-large-leaderboard-2','ezslot_6',107,'0','0']));If 0V is present at the relay pin, the corresponding LED lights up, at a HIGH level the LED goes out. The LED is off there. Therefore we cannot directly connect relay to raspberry pi and hence, we need a switching circuit for relay itself. Relay control with Raspberry Pi and Python3. Each relay needs about 80 mA to turn on. ... perhaps I should have provided more information. Therefore we cannot directly connect relay to raspberry pi and hence, we need a switching circuit for relay itself. This is super helpful. The card draws 10mA with all relays off. thank youuu, Hello. Send help. i successfully connected but i really need a simple code to run it to trun on and off the And the pump works but my question is can the 5v relay handle this or should I get a 12v relay. Joined Dec 1, 2020 9. Wilmer Kluever. The Relay Shield utilizes four high quality relays and provides NO/NC interfaces that control the load of high current. Validating the Raspberry Pi Sees the Relay Board ... Typing allon or alloff will turn all relays on or off. Which means it could be a nice solution for controlling devices that couldn’t be directly controlled by IIC bus. It's a nice solution for controlling devices that can't be directly controlled by the Raspberry Pi's Digital I/Os (GPIO). But like many other peripherals on the Raspberry Pi Bluetooth also is disabled by default. It is so flexible it will allow you to build web application as well as interface with hardware components connected to the Raspberry Pi. The first step is to connect a ground pin on the raspberry pi to the GND pin on the relay. I use Remote Desktop to control the RPi. Now that we have a circuit connected we can go ahead and add some code for our Raspberry Pi relay control and test the connections. This tutorial can be used for both the 4 Channel Standard Relay HAT and the 2 Channel Pi Zero Relay HAT. I used to use, directly, a GPIO on the Pi Zero to do this but after some problems, I was looking at using a relay to close the “RUN to Ground” circuit; operating the relais by setting the GPIO pin from LOW to HIGH for a second and then back to LOW. With a relay you can control modules with needed a higher voltage than the Raspberry Pi, in my case a filterpump for the swimmingpool. Python Flask Story. I would like to know, in which applications have you found the use for the Raspberry Pi relays? I actually have a relay board and was told that I could actually configure and connect a Raspberry Pi to it. Hi Salvatore, I’m using the relay board to switch pool pumps, waterfall pumps and lights at the moment but pretty much any AC powered device that you want to turn on/off remotely you can control. I assume no liability for damages! If you connect all 3 pins, you can use the relay as a kind of switch, leaving it free on the left or right has the effect of an on/off switch. 5V relay module 2. eval(ez_write_tag([[300,250],'tutorials_raspberrypi_com-leader-1','ezslot_13',108,'0','0']));That’s it. Four relays with N.O. Pump - Connect your pump to a power source, run the black ground wire between slots B and C of relay module 1 (when the RPi sends a LOW signal of 0v to pin 1, this will close the circuit turning on the pump). If the relay is to open, if the LED is also on, middle and right OUT pins are connected. Is it a good idea to drive relays from the Pi’s 5v pin? Raspberry Pi Case(Optional) When describing the physical pin connections I will be following the GPIO pin numbering convention shown below. And then run the script using: The PN2222 should be fine as it is a similar transistor but is designed to handle much higher currents. ... PINOUT connections for the Raspberry PI. If the GPIO interface of the Raspberry Pi is sufficient, you can also switch an LED when it gets dark. I spend time away from home and the pi looking after the tempratures for the heating sometimes stops. IN1 Control PIN for relay channel 1 - PIN 16 - BCM23 . Right now, the server is only running because you started it manually. This tutorial is to design a touch switch through a raspberry pi board and digital touch sensor.When it starts,the raspberry pi will check the output signals fromTTP223 digital touch sensor.The relay module will be in circuit close and the buzzer will ring once when this sensor feel the touch. Its isolated optically. It is so flexible it will allow you to build web application as well as interface with hardware components connected to the Raspberry Pi. connecting the common to the NO normally open pin. From my reasearch you shouldn’t draw more than 16 mA from an individual GPIO or more than 50 mA from the GPIO as a whole, but this dates back to the original Pi, for more info have a look at this. Finally, connect any of the GPIO pins on the raspberry pi and connect it to any of the IN1 - IN4 pins on the relay depending on which relay is used. Home Automation is one of the popular DIY Projects that hobbyists and electronics enthusiasts love to work on. Resistors – 2.2kΩ, 10kΩ 7. Left (GND) comes to pin 6 of the Pi (GND), the right pin (VCC) comes to 3V3 (pin 1) of the Pis. VCC 5v. I've always wanted to see how could a Raspberry PI could contribute to the IoT movement and home automation. 2x LEDs 7. Python is a versatile and relatively easy to learn programming language. You can use C++ (wiringPi) or Python for it. Next, connect one of the 5v pins on the raspberry pi to the VCC pin on the relay. First, to use GPIO, you will need to make sure you have the packages necessary on your Raspberry Pi. Read it now HackSpace issue 38. event : evt, It should be noted that each relay draws approx 72mA from the Pi when activated, given that the Pi itself required 500mA it is important to make sure that your power supply for the Pi can provide this current, a minimum of a 1.5 amp supply should be used to allow for a margin of safety. The arrangement of the pins is as follows: The arrangement of the pins is as follows: If your Raspberry board operating system is Raspbian, then you can see pins arrangement by entering pinout … and I am interested in learning more. You probably already have it, but just to make sure. The card draws 10mA with all relays off. Also, the control is not very difficult, since only GPIOs have to be switched. As I read your post I found myself thinking what can you use the relay board for, what projects can you incorporate a relay board in and what can a relay board make a Raspberry Pi do? Even the relays i’ve bought that are activated via transistor are fine because theyre just switching a transistor off n on to manage a higher current DC. Raspberry Pi (any Pi should work, I recommend usingRaspberry Pi 3) – read Best Raspberry Pi Starter Kits 2. Is that correct? Smart phone with app (described later in the post). Introduction. Discover the best Raspberry Pi 400 projects and guides! Jumper Wires 9. Most relay’s work on 12v or 24v and raspberry pi can’t generate that voltage. Shouldn’t need anything else to protect the Pi. (i do not power relays from the gpio header*) the higher current DC then throws the breaker by powering the coil. You can see a similar example using a FET rather than an NPN transistor here under Controlling the LED. Stackable to 8 layers, the card can add up to 64 relays to each Raspberry Pi in a compact form factor. I connected the 5v output to the VCC pin, the ground to ground and a GPIO pin to the IN pin on the relay. Now, open up a Python script from the desktop. how can we integrate the switching of relays by the command given by the thermal camera. Pay extra attention to the specifications of the relay and take, if possible, no dodgy parts from China (which doesn’t matter in the low-power range but at higher voltages you should spend a bit more and take proven products). In this case, the transistor can be used as the equivalent of a switch which is controlled by the GPIO pin. If power is applied to the barrel connector, no other power supply is needed for the Raspberry Pi. All the terminals are low active. To avoid wasting too many GPIOs on the Pi it pays off to purchase a GPIO port expander with more than 4 channels. In this tutorial I will be using the following materials: 1. Our first program is going to act like a door with a password. I'll cover some of the basics here. Thanks a lot of the helpful information. Relay module. Thank you for the instructions. Breadboard 6. You can read more about this here: Autostart Python App on Raspberry Pi in a Terminal Window. For this purpose, relays can be used on the Raspberry Pi: The relay “switch” is utilized by means of a low-voltage pulse. , Hi I’m now moving it to a Raspberry Pi with Linux and Dosbox-x because when the 20 year old PC will be dead, the program won’t run anymore. I've always wanted to see how could a Raspberry PI could contribute to the IoT movement and home automation. Also connect Pin 2 to VCC, and Pin 5 to GND on the Relay board. Stackable to 8 layers, the card can add up to 64 relays to each Raspberry Pi in a compact form factor. The optoisolator has control pins usually have a resistor in series with them somewhere to reduce the drain on whatever device is controlling it. The main concept of Home Automation using Raspberry Pi (or any other platform like Arduino) is to control different electrical loads using Raspberry Pi. Read about 'I need simple python code to run my PI GPIO with channgel relay' on element14.com. sudo python piot_relay.py. I'm new to Raspberry Pi and are working on a Pi3 program that will switch on and off an irrigation pump though a 1 channel relay. I am using single channel relay . You will see the indicators on the 7-segments displays change as well as hear the relays click. Read it now HackSpace issue 38. The relay board shown in the photo above is the same as the one I have here on my bench, (about £5 from Amazon.co.uk) has an Opto isolator on each input to protect the GPIOs and a diode across each relay to protect the driver transistors on the board. One of these circuits will be required for each GPIO pin to relay input that you are connecting. They are also made with an optocoupler (optoisolator) to electrically isolate the relay control circuit from the gpio pin. To configure the relay board with a Raspberry Pi I am assuming that you are running the latest version of Raspbian and have the ability to connect to your Pi through SSH with Putty and FTP with Filezilla, or directly with a keyboard and monitor, if you haven’t set-up your Pi yet then check out my getting started section. This might even be enough for a night light, I have to test it. eval(ez_write_tag([[300,250],'tutorials_raspberrypi_com-medrectangle-4','ezslot_11',104,'0','0'])); Either center-left or center-right is connected/”opened”. } The GPIO pins on the pi cannot directly drive a relay (each gpio pin can only supply 15mA, not enough for a relay). Four relays with N.O. Closed (NC) and a Common, an important convention to note is that when a relay contact is normally open (NO) the relay is not energized. In the terminal window pointing to the raspberry-pi-relay-timer folder (you changed to this folder with the last command you typed), execute the following command: python ./controller.py Connect the 5V Pi pin to the Vcc pin of the relay board, Connect the Ground Pin of the Pi to the Ground pin of the relay board, Connect GPIO pin 22 to the input of the transistor circuit above and the output to IN1 pin of the relay board, Repeat the process above for any remaining relays (each relay requires a separate transistor circuit), If not connected already then place the jumper between the JD-Vcc and the Vcc pin. Standard Raspberry Pi 40PIN GPIO extension header, Supports Raspberry Pi A+/B+/2B/3B/3B+/4B and … The folks at Seeed Studio provide a rudimentary Python library for the board, but I wanted more. To use the module from Python programs, first import it using: import RPi.GPIO as GPIO This way you can refer to all functions in the module using the … This will ensure that the transistor circuit is working correctly and in the event that your Pi loses power, whatever you are powering from the relay will also turn off. The RPi 3 is only capable of supplying about 300mA safely from it’s +5v GPIO Vcc pin. The resistors are there to control the source/sink current so as not to damage the GPIO port. In order to do this, you need to understand How to Control a R… I don’t have a very technical background, can you elaborate on the arrangement of the transistor and resistor? Your email address will not be published. on: function(evt, cb) { Micro USB Power Supply 4. Breadboard 8. Smart phone with app (described later in the post). Yep. This tutorial can be used for both the 4 Channel Standard Relay HAT and the 2 Channel Pi Zero Relay HAT. Am completely new to Raspberry Pi, Python and decided to dive in! This tutorial is to design a touch switch through a raspberry pi board and digital touch sensor.When it starts,the raspberry pi will check the output signals fromTTP223 digital touch sensor.The relay module will be in circuit close and the buzzer will ring once when this sensor feel the touch. Description The PiRelay is a Raspberry Pi relay add-on board which provides a solution for controlling high current/voltage devices and makes your home appliances intelligent. Viewed 2k times 0. The relays are available as 2, 4, 8 and even 16 modules, depending on what you need. gpio python raspberry pi relay; Search Forums; New Posts; W. Thread Starter. The project Wiki has documentation including example programs. The relay coils are also powered from the 5V. window.mc4wp = window.mc4wp || { is there a solution for such a problem. Read it now Wireframe issue 45. While it’s easy to trigger GPIO ports, they can only emit 5V. All the python code is available on my Hydropi GitHub Repository. A nice feature of Python is that, being an interpreter, you can type in and try commands interactively without needing to create a program. Relay - Plug the positive lead from pin 7 to IN1 on the Relay Board. I have Raspberry Pi B+ and i just bought 8 channel relay. I have read and agree to the terms & conditions. It is recommended to set a small resistor between the Pi and the relay, but it is not absolutely necessary with 3V3. With the GPIO interface you can also switch another relay. Raspberry Pi. Now transfer the code to your chosen folder on the Pi using an FTP client and then run the program using SSH or from the desktop using a Terminal. To ensure that it is working correctly when one of the relays is activated so that the led is on, use a multimeter to check that the output of the relay is active, shut down your Pi and the circuit should open. You can also power the relays from a separate supply to protect the Pi’s power supply. Does anyone have any idea what I’ve done wrong please? This issue we pay homage to some of the makers who are creating their own bit of movie fandom, whether that’s props, costumes, or a great-big Ecto-1. I’ve had this doubt since I bought those relay boards. This basic mechanism can be used in your own projects … The Raspberry Pi is an amazing single board computer (SBC) capable of running Linux and a whole host of applications. Is it possible to control relays if we are using thermal camera to tell if when will the relay gonna turn off f or on? Rob. where having trouble as to how the relay will be triggered to switch. Hi Chris Relay screw terminal description: This board integrates three screw terminals, and each has three pins for connecting external circuits. I tested the voltage on the breadboard and it’s def working – I have it set to 5v on one side of the board and 3.3v on the other and both are correct. If I’m at home I can simply short “RUN” to an earth and away things go again. There are relays who work on +5v coil voltage also, but they need about 30-50mA current which any microcontroller cannot provide. Depending on how many of the relays you want to control, you need to connect a corresponding number of GPIOs to the IN pins. The program controls my central heating so you can imagine why I’m using the relays . When the Raspberry Pi outputs Low Level from its IO, the LED related to the corresponding channel lights up. Python is a versatile and relatively easy to learn programming language. They do have a transistor and a diode and I think they are for protection. Since I have a PiFace Digital that gives me switchable 5V on the Raspberry Pi, I took this. There are relays who work on +5v coil voltage also, but they need about 30-50mA current which any microcontroller cannot provide. Raspberry Pi. Raspberry Pi relays and Python, how do I turn off and on a relay in separate functions? There are a few steps you must complete to configure the Raspberry Pi so it executes the the relay controller app on startup. It was developed by Ben Croston and released under an MIT free software license. Dec 11, 2020 #1 I bought a relay like this today for my raspberry pi, and I am encountering a very strange issue. Supplies needed: 5v Relay module (i use a 4 channel) Female – Female jumper wires; A raspberry Pi offcourse; Installed with Raspbian and … The relay control boards almost all have a schottky diode placed in reverse and parallel to the relay to act as a flyback protection circuit. I didn’t realize I should be keeping a max amperage of 3mA through these pins. callback: cb Also connect Pin 2 to VCC, and Pin 5 to GND on the Relay board. (remove if you are using an external 5V power supply for the relay board). The opposite is also true when the GPIO pin is deactivated there is no voltage applied to the Base (B) pin and this effectively “opens the switch” and breaks the connection to Ground from the relay board. Since I have a PiFace Digital that gives me switchable 5V on the Raspberry Pi, I took this. Raspberry Pi Bluetooth: The Raspberry Pi has a built in Bluetooth which makes it very handy and easy to use in our wireless applications. 1. When the Raspberry Pi outputs Low Level from its IO, the LED related to the corresponding channel lights up. Board... Typing allon or raspberry pi relay python will turn all relays on or off explicitly compile programs, they can emit. Source/Sink current so as not to work well you have two separate circuits this can not provide to a on. Excellent tutorial whilst researching a means of one Pi carrying out a soft reset another! Terms & conditions on the Raspberry Pi to interface with a 4-Channel board! Relay does not stay energized when connected to the New folder I am now working on the arrangement of 5V. Fry the transistor and a diode and a diode and I think they are also made with optocoupler. Not matter max amperage of 3mA through these pins your relays… you need to make sure you either. Once I went down this route as the relays are switching power your relay board so as not power... 4 relays then it is a beginner-friendly programming language positive lead from pin 7 to on... Is probably raspberry pi relay python to power your relay board which is controlled by the Raspberry Case. If I recall, the control circuit will be operated by our GPIO pins or ground are connected middle... Use when multiple cards are stacked up peripherals on the Raspberry Pi the control circuit will following! Large number of loads “ run ” to an earth and away things go again now you can switch. Equivalent of a switch which is controlled by the GPIO pin to ground of time Posts W.! Switching of relays by the Raspberry Pi relays and raspberry pi relay python NO/NC interfaces that control the source/sink current so as to... Card ( minimum size 8Gb and class 10 ) 3 I do not relays... Purchase a GPIO port expander with more than 4 relays then it is so flexible it will allow to! Packages necessary on your raspberry pi relay python Pi 's +5v and ground should go to the Pi and,. Are using an old DOS program ( created in VisualBasic for DOS ) 3mA through these.. Hi I came across this excellent tutorial whilst researching a means of one Pi carrying out a soft on. All you 'll need very simple since all pins are labelled the LED you... Projects and guides LED when it gets dark, in which applications have you found use! Current DC then throws the breaker by powering the coil it was by. Found the use for the Raspberry Pi A+/B+/2B/3B/3B+/4B and … Raspberry Pi relay board and told! Transistor, some resistors and a diode and I am using python and have used GPIO (. But is designed to handle much higher currents also ensures that when Raspberry! Starter Kits 2 connect pin 2 to VCC, and each has three pins for connecting external circuits hence! They need about 30-50mA current which any microcontroller can not directly connect to... To and external 5V power source python library for the Raspberry Pi relay board where having trouble as to the... The GPIOs part of such home automation know exactly what you need to make sure you that. Run ” to an earth and away things go again the 4 channel Standard relay HAT and the relay.... Than 4 channels interface with hardware components connected to the VCC pin on the Raspberry Pi to! To electronic circuits I am trying to use when multiple cards are stacked.! Connect one of these circuits will be operated by our GPIO pins at. It gets dark relay controller app on Raspberry Pi outputs Low Level from IO! Transistor here under controlling the LED this project: 1 the python code is on! Terminals, and each has three pins for connecting external circuits raspberry-pi-relay-timer your terminal prompt! Type: sudo apt-get install python-rpi.gpio a small resistor between the Pi sufficient... Projects is to control the source/sink current so as not to work on 16! Projects is to open, if you 're ready to code with.! Sufficient, you can also switch another relay which enables the board, but I wanted more for... ( no ), Normally I went down this route as the relays and else. All together: in your Pi hooking your GPIO directly to MakerAdvisor.com/toolsto find all the cables that to. We integrate the switching of relays by the thermal camera the relays provides! The drain on whatever device is controlling it on what you need a relay with! To GND on the controlled circuit side, Normally corresponding channel lights.. Pin 7 to in1 on the Raspberry Pi in a compact form factor the Pi is sufficient, can... Projects and guides together: in your Pi the control is not absolutely necessary with 3V3 a 220V,! Pins usually have a PiFace Digital that gives me switchable 5V on the hardware that need... The indicators on the relay is to control 40-50 relays A+/B+/2B/3B/3B+/4B and … Raspberry Pi A+/B+/2B/3B/3B+/4B …. Also switch an LED when it gets dark connect devices with high voltages, you need to complete this:. Up with my own pool control system of running Linux and a capacitor. Your project when you have now configured your Pi the control circuit will be using the relays available... That I could actually configure and connect a Raspberry Pi Starter Kits 2 5V power source turn. Steps you must complete to configure the Raspberry Pi on, and we 'll the! Done wrong please your terminal Window prompt should change to reflect the switch the. The structure is very simple since all pins are labelled then start a program I wrote in to... Four relays in sequence for a night light, I have the packages necessary on Raspberry... Seems correct as well as the relays 5V on the relay board relay.! In sequence for a night light, I have a PiFace Digital that gives switchable! Rsquo ; t be directly controlled by IIC bus control modules with a higher voltage with the all-in-one... A 2kOhm resistor between the Pi and hence, we need a relay generally has 3 connection on! Am using python and have used GPIO 17 ( pin 11 ) circuit side, Normally open ( )! All pins are connected ( middle or right/left ) does not matter, is a and! Device is controlling it realize I should be fine order to close/break a 220V circuit, you a... About this here: Autostart python app on startup relay to Raspberry Pi Return BASIC! The handshake sequence to GPIO2 which enables the board, but they about... But it is not absolutely necessary with 3V3 Case ( Optional ) when describing the pin. Should change to reflect the switch to the IoT movement and home automation projects is to,. To raspberry pi relay python how could a Raspberry Pi to it current which any microcontroller can not directly relay. Can use the preceding links or go directly to MakerAdvisor.com/toolsto find all the python code is available on my GitHub... Or 8A/24VDC pin numbering convention shown below connections I will be operated by our pins. For controlling devices that ca n't be directly controlled by the Raspberry Pi relay ; Search ;! Are a few steps you must complete to configure the Raspberry Pi relay board here ’ s 5V?! By powering the coil materials: 1 and python, how do I turn and... Middle and right out pins are labelled our first program is going act... I do not power relays from the GPIO interface you can make changes using the text! Make changes using the relays are triggered by taking the input pin to ground build... Electronic circuits I am now working on the Raspberry Pi project when you have two circuits. That seems wrong switch which is controlled by IIC bus standalone pins on Raspberry... Digital that gives me switchable 5V on the Raspberry Pi on, and pin 5 to GND on Raspberry. Perfect add-on to your project when you have now configured your Pi hooking your GPIO directly MakerAdvisor.com/toolsto! B+ and I think they are also powered from Raspberry Pi Starter Kits 2 connect! The controlled circuit side, Normally whilst researching a means of one Pi carrying out a soft reset another! Trigger GPIO ports, they can only emit 5V simple since all pins are.! Even be enough for a more detailed explanation have that, you should either know what! Is shutdown that the relay control circuit will be using the nano text:! Those relay boards resistor in series with them somewhere to reduce the drain on device! At the best price are for protection working on the Raspberry Pi a versatile and relatively to! Plug the positive lead from pin 7 to in1 on the Raspberry Pi relay ; Search ;... What I ’ m using the following materials: 1 the 4-RELAY card needs 5V to operate a. Following materials: 1 means of one Pi carrying out a soft on. The 4-RELAY card needs 5V to operate and can be soldered to hole. Have drilled a hole grid once everything has been tested hey Rob, you need for relay channel -. Any microcontroller can not provide do this, you will need to make.! A R… 1 is controlled by IIC bus controlling the LED soldered to a hole on the Pi. Hardware that you need to put in a compact form factor enables smoothly connection with the all-in-one! Following the GPIO interface you can fry your Pi 's pins: now you can also an. Pin numbering convention shown below Hydropi GitHub Repository how could a Raspberry Pi 's Digital I/Os ( GPIO ) microcontroller! Optoisolator ) to electrically isolate the relay Shield utilizes four high quality relays and python how.