Controlling Multiple Solenoids With Arduino

Note: The board ships as pictured, without Arduino headers. Controlling Solenoids With Arduino: In this instructable we will be building a simple circuit that will allow us to control a solenoid using the popular physical computing platform arduino. This module is able to control multiple connected modules with the Pneuduino library and can be programmed via USB through the Arduino IDE. Adafruit Industries, Unique & fun DIY electronics and kits : Sensors - Tools Gift Certificates Arduino Cables Sensors LEDs Books Breakout Boards Power EL Wire/Tape/Panel Components & Parts LCDs & Displays Wearables Prototyping Raspberry Pi Wireless Young Engineers 3D printing NeoPixels Kits & Projects Robotics & CNC Accessories Cosplay/Costuming Halloween Reseller and School Packs Internet of. Powering Multiple solenoid valves with one arduino (self. The opto-coupler must be connected with the transistor the right way around or it will not work (or melt, or create a black hole) To ditch the opto-coupler you can just treat it like any other load on the Arduino (as long as the MOSFET's threshold voltage V GS is. I have already done other projects with capacitive touch on the arduino (actually the teensy 2. two, are utilized. i have a 17 dof robot controlled by a torobot usc32 servo controller, running the torobot software through a usb cable. Lab: Using a Transistor to Control High Current Loads with an Arduino Introduction In this tutorial, you'll learn how to control a high-current DC load such as a DC motor or an incandescent light from a microcontroller. You can actually change the DC Fan to other electrical devices such as light or servo motor. Arduino is a small $15 circuit board with an Atmel MicroController chip and other parts. Arduino on Sale. One of the most popular Arduino boards is known as the “UNO”. "Uno" means one in Italian and is named to mark the upcoming release of Arduino 1. Before you get started, there is one simple process for uploading a sketch to an Arduino board that you can refer back to. , Experts in Manufacturing and Exporting IC, Transistor and 10372 more Products. How to Build an H-bridge Circuit with an Arduino Microcontroller. This type of solenoid is normally used for starting motors. Think about a pencil. With an H-bridge, motors can go forward or backward, left or right, up or down, etc, depending on the use of the motor(s) in the circuit. In the Arduino enviroment, the PWM signal (analogWrite) is most commonly used to control something i. It requires more current than you can provide and produces destructive voltages when it is switched off. What are the advantages and disadvantages of using relay boards vs transistors with muultiple outputs?. In this post we are going to construct a farmer friendly GSM pump motor controller circuit which could turn on and off the irrigation system remotely from anywhere in the world via cellphone SMS and return you with an acknowledgement message. All our products are industrial-grade and made to deliver dependable performance for years to come. The PSU should be able to drive multiple solenoid, it's 7. Valves for Pneumatic Cylinders | Actuators. Harlan Russell. i have fitted one mega to the robot servo controller,arduino tx to controller rx, a common gnd plus power to each, could you show me a mod to your sketch to run the servos. If you add 1 to an unsigned long holding the maximum value of 4,294,967,295 the answer will be 0 (zero). For more on Servo motor control, see this lab: Servo Motor Control with an Arduino, and this video: Analog Output – Servo. Arduino - Controlling multiple 12v motors. Just send text out the USB when you want the servo position to change. Re: Controlling Electromagnets with a Microcontroller, Arduino or Raspberry Pi Using solenoids for "long" movements requires a high-power DC input, and the force is weak at the larger distance. Pneumadyne’s direct acting pneumatic solenoid valves are a cost effective, space saving solution for the use of single or multiple valves. We are well on our way to building some really powerful projects. Most useful hardware requires significantly more power to operate than can be supplied directly from an Arduino output. a top quality 60a rc tiger speed controller. One simple example is controlling an array of LEDs. Using the Arduino to control the solenoid valve is simply a case of setting a pin high for the appropriate amount of time. All About Turnouts. I am using some shift registers to cut down on the Arduino pins I need. Please help! 😁' on element14. Transistor is wired as a switch which carries the current required for operation of the relay. When the pin RB7 of the PIC microcontroller goes high, the transistor BC547 turns On and current. mention some Arduino processing power. Adafruit Industries, Unique & fun DIY electronics and kits Plastic Water Solenoid Valve - 12V - 1/2 Nominal ID: 997 - Control the flow of fluid using the flow of electrons! This liquid valve would make a great addition to your robotic gardening project. The FQP30N06L is a N-Channel MOSFET and can switch up to 60V DC at 32A, this is more than chunky enough for the solenoid. A microcontroller isn't very useful without some kind of hardware attached. The key thing to note here is that the A4988 only requires two inputs from the Arduino to control the stepper motor and does not need the Arduino to "figure out" the stepping logic. Connecting multiple Servo Motors with Arduino seems to be easy and but if we connect all the Servos to Arduino supply pins then they won’t work correctly because of lack of enough current to drive all the motors. I was wondering how I could connect multiple 12v solenoids (more than the 53 allowed on mega because of the pins) on the Arduino Mega 2560 to get it to control the keys on a piano/keyboard/organ. That means, here to make an arduino uno like this case, and it needs an arduino. The valves are normally closed (NC) type which I guess in that context means they open and let the water drain only when they receive ON signal at their input. Sometimes it's not a bad idea, but more often than not it's an over-powered and somewhat frustrating way to go. Linear solenoids are useful in many applications that require an open or closed (in or out) type motion such as electronically activated door locks, pneumatic or hydraulic control valves, robotics, automotive engine management, irrigation valves to water the garden and even the “Ding-Dong” door bell has one. No worries about interrupts on the Arduino. In my head, I imagined that I would have an easier time controlling DC valves (as I was planning on using Arduino and Raspberry PI. Let me show you how to operate relays and control GPIO pins with the Pi using PHP and a temperature sensor. The if statement can be followed by an optional else ifelse statement, which is very useful to test various conditions using single ifelse if statement. 5V) exists then we know the MOSFET is suitable. So what type of motor can do this? I've been reading about rotary encoders, but I want to control the motor position with code/feedback from the motor and not a separate switch. 2016-06-30 Cheap Arduino SD Card Reader. It consists of a resistor array, wiper switches, a control section, and non-volatile memory. The MegaMoto is the first and only motor control for Arduino that gives users the ability to control up to 30A of current at up to 28V. The FQP30N06L is a N-Channel MOSFET and can switch up to 60V DC at 32A, this is more than chunky enough for the solenoid. LED brightness control using arduino. com, it can control DC motor 7-12V DC , current load up to 5amps. Moving on from Tutorial 1 where we flashed an LED on for a second then off for a second in a continuous loop. Selecting the right air control valves to regulate system pressure, direction of flow, and rate of flow is crucial when designing fluid power circuitry. You already know it can be used for the dimming of LEDs and controlling the angle of servo motors and now you can begin to explore other possible uses. We feature an expansive collection at the best prices. Why do rocket engines use nitrogen actuators to operate the fuel/oxidiser valves instead of using electric servos? Stack Exchange Network Stack Exchange network consists of 175 Q&A communities including Stack Overflow , the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. Choose from two-, three- and four-way models. Can anyone suggest me which mux( component name) can be. Commercial Multi-Zone Heating Controllers (like EvoHome. In an irrigation system, a number pumps and valves are used to properly convey a controlled flow of water to a designated area in a field. Solenoid valves use electromagnetic levers to help control air release and can make compressors safer and more efficient. MegaMoto Plus Motor Control Shield for Arduino The Robot Power MegaMoto Plus™ is a low-cost robust H-bridge "shield" for the Arduino™ and hardware compatible base units. Proportional Valves ASCO Proportional Valves control the flow of neutral fluids. I don't have the N-channel power MOSFET yet, I understand you need this and a diode to get started. Stepper Motor. Note that the distance between digital pins 7 and 8 is 160 mil (0. In this tutorial we will be controlling a solenoid with an Arduino and a transistor. I am using 2 way so I can turn lights on in a garden room by a switch but also remotely with Blynk(via an arduino controlled 2 way relay) from the comfort of my house. readDigitalSignals This example assumes there are push buttons with pullup 10 kOhm resistors connected to the 16 channels like in the following figure. The package enables you to perform tasks such as:. This is because current control raises or lowers the voltage to control the current. Driving Large Loads with the Arduino. For this, it uses the Arduino flight controller board along with various sensors, such as gyro scope and accelerometer. This indicated (along with the LED on the control board) that the relay was actuated to the 'on' position. The smart solution to control multiple zone heating in your house, Controlling the Floor Unit pump will save you over 150 Euro/Year! Multi-Zone Heating Controller Project tutorial by erkr. Multiple processes. I was wondering how I could connect multiple 12v solenoids (more than the 53 allowed on mega because of the pins) on the Arduino Mega 2560 to get it to control the keys on a piano/keyboard/organ. We have learned how to control commands with both for loops and while loops. In arduino based system both digital and analog outputs of the sensor can be used as an input signal. Solenoids can be connected to your Arduino/Genuino Uno or Mega and L298 H bridge module using any of the inputs and outputs, as shown in these examples:. In this project, we will go over how to integrate a keyboard with an arduino board so that the arduino can read the keys being pressed by a user. The FQP30N06L is a N-Channel MOSFET and can switch up to 60V DC at 32A, this is more than chunky enough for the solenoid. You basically have an In called the Source, an Out called the Drain, and a Control called the Gate. Remove the Vcc to JD-Vcc jumper. com, that makes a board they call the "Mini-Maestro" which will controll multiple servos, you just tell it where to go via USB serial text, it handles the 50 times per second part. That means, here to make an arduino uno like this case, and it needs an arduino. I became interested in controlling solenoids for robotic music applications. Still searching for affordable Home Kit Switch from Consumer Electronics, Replacement Parts & Accessories, Gamepads, Lights & Lighting? Online Buy 2018 high quality, low price Home Kit Switch. If you need to power things like relays, solenoids, or motors, you will need to use transistors, and pass through the channels only the control signals. In this project, we are going to build something very simple project, a temperature controlled relay that is used to turn on a dc fan. There is, however, a caveat, the solenoid works at a different voltage to the Arduino and you cannot directly connect the two. Let me know if you need more details and thanks for your help in advance!. If you already played with an ESP-01 module, the uploading firmware process is exactly the same, you can easily. In an irrigation system, a number pumps and valves are used to properly convey a controlled flow of water to a designated area in a field. There is a simple solution. I am absolutely a complete novice and like many, this really seemed like it would be very difficult to learn. Thanks in advance for your help. With an H-bridge, motors can go forward or backward, left or right, up or down, etc, depending on the use of the motor(s) in the circuit. mention some Arduino processing power. For the wiring, we ordered a 20 cm dupont cable male to female (Phantom YoYo 40P dupont cable 200mm male to. The valves I need to control using the labview are: a) Pressure Reducing Valve (open & close) b) Remote control Valve(On & Off) with in-built actuator. A stepper motor is a motor that has multiple coils, not just one. Arduino is intended for use by both non-technical people with no previous programming experience and seasoned pros who love to tinker. This example shows how to control the speed of a DC motor an LED on pin 9 using the analogWrite() function. This indicated (along with the LED on the control board) that the relay was actuated to the 'on' position. com, that makes a board they call the "Mini-Maestro" which will controll multiple servos, you just tell it where to go via USB serial text, it handles the 50 times per second part. Debounce: read a pushbutton, filtering noise. You can connect the module directly to your Arduino/Genuino Uno or Mega without soldering using the supplied connector, and then control your solenoids from MECControl. This is my first time posting and it's about my first electronics project since school. Read before buying. Designed by Lensen--Wireless Communication, Ships from China. Arduino solenoid valve control circuit. This is a draft it still has a ways to go ( and with other micro controllers, the PIC …. IRJET Journal. mention some Arduino processing power. The Adafruit 16-Channel 12-bit PWM/Servo Driver will drive up to 16 servos over I2C with only 2 pins. The DC motor controller has been designed using Multi-purpose LCD Arduino Nano shield, circuit, PCB layout and Arduino code available at our website www. In this article you will learn how to control a stepper motor with the L298N Motor Driver. Buy SparkFun Analog/Digital MUX Breakout CD74HC4067 in Dubai,Abu dhabi,Sharjah or anywhere in the UAE at Edwin Robotics. /* Controlling a Solenoid with Arduino This demo shows how to control a solenoid using pushbuttons and a relay with your Arduino compatable controller. Economizer circuits embrace the physics of solenoids and relays to bring power savings control to regulate the means that you can use a single solenoid design in multiple products. When the pin RB7 of the PIC microcontroller goes high, the transistor BC547 turns On and current. If a buzzer operates from a low enough voltage and draws low enough current, it can be interfaced directly to an Arduino Uno pin. So whenever there was a gas leakage the solenoid valve would close automatically. If the pneumatic valve is too big for your application, you will be wasting air and money. Control multiple solenoids using PIC12f675? Learn how to use a Raspberry Pi and an Arduino to develop a system for monitoring and controlling your home. If you already played with an ESP-01 module, the uploading firmware process is exactly the same, you can easily. com, it can control DC motor 7-12V DC , current load up to 5amps. Read about 'Multiple Arduino functions without delay' on element14. Working with Arduino platforms (if you are new to Arduino – see this article link to learn more). Arduino solenoid valve control circuit. Hot Network Questions. The extensive line of solenoid valves from ASCO also includes nuclear products, navy/marine solenoid and air operated valves, modular fuel gas shut-off valves, composite valves, spool valves, redundant control systems and electronically enhanced Next Generation valves. A separate ground must be connected and this type of solenoid can be mounted on any surface. While using with digital signal arduino can only read the input as a HIGH or LOW state. What's All This Solenoid Driver Circuit Stuff, Anyhow? [Mod edit: dysfunctional link removed. ArduCAM is a startup company dedicated to open source hardware and software, designed and manufacured in China specifically for Arduino and Raspberry Pi camera solutions. The standardized shield format stacking headers allows multiple MegaMoto Plus units to be controlled by a single Arduino Uno or Duemilanove using pass-through stacking headers. In the pneumatic world, valves are the equivalent of relays controlling the flow of electricity in automation systems. Keypads are used in all types of devices, including cell phones, fax machines, microwaves, ovens, door locks, etc. One of the most popular Arduino boards is known as the "UNO". What's All This Solenoid Driver Circuit Stuff, Anyhow? [Mod edit: dysfunctional link removed. The pins are 4 (S0 to S3) to select the solenoid for each Demultiplexer/Decoder, and the E1 and E2 pins (Probably I will need to separate them and change JP2 to a 12 pins connector). D1 must be connected reverse biased or it will just short out your solenoid. Introduction This webpage describes control systems that are used to operate the Fusor. The page lists down all the projects made using esp8266 wifi module. The circuit for controlling the solenoid valves uses the transistor as a switch. So what type of motor can do this? I've been reading about rotary encoders, but I want to control the motor position with code/feedback from the motor and not a separate switch. So, your example, you could only run the 1 solenoid? If you wanted multiple, you'd have to up the amps, right? If you had 2A output, you could run 3 of those solenoids concurrently? I'm not sure of the draw for the solenoid that I have, I guess the best way to find out is to use an ammeter while active?. With the relay module you can control almost any AC electronics appliances (not just lamps). AC powered lights, fans, pumps, etc. Large linear actuators traditionally have five wires. 2016-06-30 Automatic garden watering system BY arduino, LCD, Buttons, EEPROM, solenoid valve, Motor and underground sprinkler. It really is a convenient part, allowing you to adjust the brightness of sixteen individual LEDs via PWM (pulse-width modulation) - and you can also daisy-chain more than one TLC5940 to control even more. One limitation of the Arduino platform is that it only supplies two external interrupts, yet many RC Systems support 8 or more channels. API tools faq deals. It’s a common mistake to assume sprinkler valves work with DC voltage. So, your example, you could only run the 1 solenoid? If you wanted multiple, you'd have to up the amps, right? If you had 2A output, you could run 3 of those solenoids concurrently? I'm not sure of the draw for the solenoid that I have, I guess the best way to find out is to use an ammeter while active?. Another connector JP2 to control the solenoids, Anything can control this, for example an Arduino, Raspberry Pi, etc. Economizer circuits embrace the physics of solenoids and relays to bring power savings control to regulate the means that you can use a single solenoid design in multiple products. Stepper Motor Working Principle. 0 cable will be attached to the board from a laptop which generates the spatial coordinates that the arm must follow and perform the specific tasks. The OM1 shield provides the following functions: - 4 channel H-bridge to control up to 4 solenoid valves for delivering multiple liquid stimuli/rewards , or airpuff stimuli. The dropController features: - Connection for camera focus and shutter trigger - Connection for flash trigger - Connections for 6 solenoid valves (image still show the 3 valve version). Hi, I am planning to control multiple solenoids with the Arduino Mega board. ArduCAM is a startup company dedicated to open source hardware and software, designed and manufacured in China specifically for Arduino and Raspberry Pi camera solutions. On the arduino you usually think of this as analogWrite. The circuit for controlling the solenoid valves uses the transistor as a switch. The DC motor controller has been designed using Multi-purpose LCD Arduino Nano shield, circuit, PCB layout and Arduino code available at our website www. So, your example, you could only run the 1 solenoid? If you wanted multiple, you'd have to up the amps, right? If you had 2A output, you could run 3 of those solenoids concurrently? I'm not sure of the draw for the solenoid that I have, I guess the best way to find out is to use an ammeter while active?. Plus our world class engineering teams can work with you to create high. The configuration is done entirely through a small LCD screen using only two buttons, so it works independently without the need for a computer (except for firmware updates) but also, you can use the Photoduino Remote Software to wide control of Photoduino. However, references to Arduino basics may appear but only in passing. Pumps generally use a universal, brushed or brushless DC motor or a single-or three-phase induction motor. Servo motors are extremely useful in so many different applications; it'd be good to learn how to control them! Solenoid and DC motor control have been shown already; for the most part, they are both pretty straightforward (only power and ground connections) methods of motor control. Applying electricity to the solenoid quickly directs air through the valve and into the circuit. In the Arduino enviroment, the PWM signal (analogWrite) is most commonly used to control something i. A stepper motor is a motor that has multiple coils, not just one. In this arduino relay control tutorial we will simply learn How to interface a Relay with Arduino. I am using 2 way so I can turn lights on in a garden room by a switch but also remotely with Blynk(via an arduino controlled 2 way relay) from the comfort of my house. Now there’s a simple way to use your Arduino or compatible to switch up to 3A at 24VDC. I read the tutorial on controlling a single solenoid with an Arduino and reviewed the diagram posted in the playground. The following example uses a standard sized servo (without any load) powered directly from the Arduino via USB. I believe the solenoids draw at most 3 A each, but this is not measure yet. A Solenoid Tutorial. The project "Arduino Fingerprint Sensor Lock" is simply fabricated around Arduino board. The valves are normally closed (NC) type which I guess in that context means they open and let the water drain only when they receive ON signal at their input. Re: Controlling Electromagnets with a Microcontroller, Arduino or Raspberry Pi Using solenoids for "long" movements requires a high-power DC input, and the force is weak at the larger distance. ForLoopIteration - Control multiple LEDs with a for loop. The commands are conveyed back to the Arduino, which then drives the remote control, which the Hex Bug receives over its usual IR link. Linear solenoids are useful in many applications that require an open or closed (in or out) type motion such as electronically activated door locks, pneumatic or hydraulic control valves, robotics, automotive engine management, irrigation valves to water the garden and even the “Ding-Dong” door bell has one. Here’s a challenge for your creative minds: use a soil moisture sensor so that you can stop the water flow as per the soil requirement. Here the system is using the analog output of the module so the arduino can read instantaneous readings from the sensor. Arduino is an open source electronics prototyping platform based on flexible, easy-to-use hardware and software (called sketch. These control systems as such are not essential for operating the Fusor but they provide automatic control of equipment in the Fusor system or are required due to the properties of some of the parts in the Fusor system, e. Depending on the application, and the user experience you want to provide, there are a number of ways to control a linear actuator. The Solenoid Valve is a great companion to the Large DC Liquid Pump and the Small DC Liquid Pump. Bionic Arduino is a set of four 3-hour classes in November 2007 hosted by Machine Project and taught by Tod E. Speed of motor can be set using trimmer potentiometer, 16X2 LCD display the Bar-Graph of speed of motor. Electrical Signals. Compatible with the most popular software in educational robotics: Arduino Learn how to program and control electronic components Mini Lab programing kit for beginners. I want to give a string of data like this:. They're practically everywhere. Problems can occur if the relay module is low triggered. I'm using the original 24v AC wall wart from the original brain. Note that the distance between digital pins 7 and 8 is 160 mil (0. These control systems as such are not essential for operating the Fusor but they provide automatic control of equipment in the Fusor system or are required due to the properties of some of the parts in the Fusor system, e. The DC motor controller has been designed using multi LCD Arduino Nano shield, circuit, PCB layout and Arduino code available at our website www. Supporting accented fonts, Left, Center, Right justification, Blinking, Intensity control. ) What are Large Loads. That way you can use it for multiple devices without having to re-wire the relay or cut into the device's power supply. We hope you've found this guide useful. The smart solution to control multiple zone heating in your house, Controlling the Floor Unit pump will save you over 150 Euro/Year! I builded this device because my kitchen was either to warm or to cold with a single thermostat in my living. 3 A at 48VDC. The schematics needed to get DCC signal into the Arduino pin 2 is also available on the Software page. They're practically everywhere. You basically have an In called the Source, an Out called the Drain, and a Control called the Gate. Continuously adjustable valves and more simple shut. Â In the above wave forms you can see that the frequency is same but ON time and OFF time are different. Wirelessly connect it to your smart home automation controller where you create the rules when it actually should run or not. Just send text out the USB when you want the servo position to change. Sometimes it's not a bad idea, but more often than not it's an over-powered and somewhat frustrating way to go. I am absolutely a complete novice and like many, this really seemed like it would be very difficult to learn. This indicated (along with the LED on the control board) that the relay was actuated to the 'on' position. I need to control eight solenoid-valves for water drainage outdoors remotely and simultaneously. Enjoy discount prices, fast shipping & award-winning customer service. You can do the same thing by plugging into the 5V and GND pins on an Arduino board. Utilize a arduino mega to read switch matrix, control playfield lamps, control solenoid driver board. This is the reason we can control a relay using 5V's from an arduino and the other end of it could be running an 230V appliance, the 230V end is completely isolated from the 5V arduino circuitry. Shop Electronic Actuator from Makerfabs, we have served 1 million makers over 100 countries. Connect a separate +5 supply to "JD-Vcc" and board Gnd. I am controlling several 2 way lighting circuits using an arduino and Blynk. The smart solution to control multiple zone heating in your house, Controlling the Floor Unit pump will save you over 150 Euro/Year! Multi-Zone Heating Controller Project tutorial by erkr. Interfacing Relay with PIC Microcontroller using Transistor. Using just three digital pins, an Arduino can control 8 output pins on the shift register. An Arduino can be used to turn devices on and off via an infrared remote. As mentioned above a lot of the relay modules available do not come with circuit diagrams. In applications where the need is great but cost may be an issue and there is little or no risk of injury due to machine failure, the Arduino is a viable option for machine automation. Multiple user configurable power modes allow the user to dial in the lowest power profile for a given application. Valve Activation. The wiper position is controlled by a three-wire interface. 3) Wireless Control of a Mobile Robot & Robotic ARM; 4) Design & Development of Direct Control Mechanism for Single & Double acting Compressed Air Pneumatic Cylinders. Overview The Arduino Motor Shield is based on the L298 ( datasheet ), which Arduino Motor Shield Rev3 (Original) - Arduino - Top Brands JavaScript seems to be disabled in your browser. A small transistor like the PN2222 can be used as a switch that uses just a little current from the Arduino digital output to control the much bigger current of the motor. There are a number of classes that represent different types of speed controllers and servos. Discussion in 'Software and Programming' started by cfellows, May 21, 2012. Controling a Solenoid Valve With an Arduino: I need to take some vacation time and unfortunately, while I don't have kids, I have bonsais. Here arduino plays a key role in setting this time period. Arduino - Controlling multiple 12v motors. Depending on the voltage of the Arduino the ON or HIGH of the Digital signal will be equal to the system voltage, while the OFF or LOW signal will always equal 0V. Let me show you how to operate relays and control GPIO pins with the Pi using PHP and a temperature sensor. Linear solenoids are useful in many applications that require an open or closed (in or out) type motion such as electronically activated door locks, pneumatic or hydraulic control valves, robotics, automotive engine management, irrigation valves to water the garden and even the “Ding-Dong” door bell has one. com, that makes a board they call the "Mini-Maestro" which will controll multiple servos, you just tell it where to go via USB serial text, it handles the 50 times per second part. Same idea with Arduino. This is my first time posting and it's about my first electronics project since school. In this tutorial we will be controlling a solenoid with an Arduino and a transistor. The square end of the USB cable connects […]. I have already done other projects with capacitive touch on the arduino (actually the teensy 2.

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