Home Automation Using Cloud Computing

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Home Automation Using Cloud Computing

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Home Automation Using Cloud Computing

Abstract: Today, we are entering post-PC era where mobile devices (e.g. Smartphone’s, Smartphone’s and Handheld tablets) are handling daily tasks that traditional desktop and laptop computers once handled. Several reports show that personal computers are no longer on the leading the edge of computing and the use of mobile devices are quickly taking over. Accompanying the shift from PCs to multi-touch mobile devices is the use and implementation of Cloud Networking. With the availability of products which integrate mobile devices and cloud networking rapidly increasing, many users can see how new technology can impact their everyday lives. In this paper we have developed a Home Automation system that employs the integration of multi-touch mobile devices, cloud networking, wireless communication, and power-line communication to provide the user with remote control of various lights and appliances within their home. This system uses a consolidation of a mobile phone application, handheld wireless remote, and PC based program to provide a means of user interface to the consumer. The home automation system differs from other systems by allowing the user to operate the system without the dependency of a mobile carrier or Internet connection via the in-home wireless remote. This system is designed to be low cost and expandable allowing a variety of devices to be controlled.

1 Problem Definition Many people are always on the move from place to place due to business demands. Some people can spend a couple of days away from their home leaving all their household appliances without any kind of monitoring and control. Some devices are left plugged into power sockets whereas others are supposed to be plugged into and out of power sockets at different intervals depending on the time of the day. All this requires an individual to manually attend to each of the devices independently from time to time. All such monitoring and control can be done without necessarily being around or inside the home. Some devices if not controlled properly consume a lot of energy which leads to extra expenditure on electricity. Therefore I propose to design an internet based home automation system which will enable one to remotely manage his/her appliances from anywhere, anytime.

2 Literature Survey Home automation: Home automation is the residential extension of building automation. It is the automation of the home, housework or household activity. Internet : The Internet, sometimes called simply "the Net," is a worldwide system of computer networks - a network of networks in which users at any one computer can, if they have permission, get information from any other computer (and sometimes talk directly to users at other computers). The Internet is now widely used as a connectivity tool for educational, commercial, and personal applications. The Internet is an exciting portal that makes it possible for users to access virtually an infinite supply of information. Microcontroller: A microcontroller is an application specific integrated circuit (ASIC) that fetches and executes instructions based on input from some user program. These devices do not have a fixed function, but rather are controlled by software. Remote control: Remote control is the control of an activity, process, or machine from a distance, as by radioed instructions or coded signals

3.1 Introduction Modern advances in electronics and communications Technologies have lead to the miniaturization and improvement of the performance of computers, sensors and networking. These changes have given rise to the development of several home automation technologies and systems. According to, home automation can be useful to those who need to Access home appliances while away from their home and can incredibly improve the lives of the disabled. Many of the home automation systems that are commercially available can be separated into two categories: locally controlled systems and remotely controlled systems. Locally controlled systems use an in-home controller to achieve home automation. This allows users complete use of their automation system from within their home via a stationary or wireless interface. Remotely controlled systems use an Internet connection or integration with an existing home security system to allow the user completes control of their system from their mobile device, personal computer, or via telephone from their home security provider. There are a number of issues involved when designing a home automation system. Should also provide a user- friendly interface on the host side, so that the devices can be easily setup, monitored, and controlled. Furthermore the overall system should be swift enough to realize the true power of wireless technology. Lastly the system should be cost Effective in order to justify its application in home Automation. To minimize the shortcomings of each system and to overcome the design issues previously mentioned, this project integrates locally and remotely controlled systems with the use of Cloud data network. This allows the system to operate without the dependence of a mobile provider, allows the system to be used with various mobile phone platforms, and allows the system to operate locally when phone or computer access is not available. Cloud networking and data infrastructure allow individuals to monitor, manage, and control their personal data points through the Internet. Each data stream is given a unique feed identification number to differentiate itself from all other data Streams on the Network. Home Automation as a Service (HAaaS)can simplify this scenario by connecting each sub-system of a home automation system directly to the cloud, and thus not only reduce the setup and maintenance cost by eliminating the need of specialized gateway and web server in each household , but also enable HAaaS providers to deliver advanced automation services to the home automation

system.Multi-user HAaaS must be necessarily based on the standard cloud computing model, in which services are made available to the general public over the Internet as long as they use the specified web application programming interface (API).Cloud computing refers to the online services provided over the Internet together with the hardware and software infrastructure of the data centers that offer those services. The services offered by existent cloud providers can be broadly categorized as Software as a Service(SaaS), Platform as a Service (PaaS) and Infrastructure as a Service (IaaS). To endorse the expediency of HAaaS, we designed and actualized a cloud connected ad-hoc wireless home automation system as a virtuous case in point of HAaaS and tested the Quality of Service (QoS) of different sub-systems working simultaneously. We also devised our own cloud so as to empower the employment of specialized shared resources and demonstrate the upright functioning of the entire ecosystem while calling attention to the advantages of HAaaS over traditional home automation systems HAaaS refers to the cloud services provided over the Internet together with the household appliances that are automated through those services. We regard HAaaS as a development of PaaS, where computer hardware, operating systems, data storage and network bandwidth are outsourced, while application and data are managed by the HAaaS provider. HAaaS users are in control of their automated home appliances and systems by using the cloud services.

To realize the amalgamation of cloud and home automation, the bridge to link cloud services with home automation systems needs to be efficient and effective. The link is essentially the Internet and the following are the two main approaches to linking: A. Internet Gateway Conventionally, smart homes use an Internet gateway to connect to the Internet , where the Internet gateway is largely a dedicated computer unit which allows coupled devices to access the Internet. In HAaaS, home automation systems and appliances may also be connected to the cloud through such an Internet gateway. Figure shows how different household appliances can be connected to the cloud by linking to a residential Internet gateway. B. Internet of Things The Internet of Things (IoT) refers to distinctively recognizable objects (things) and their virtual representations in an Internet-like structure . In HAaaS, individual home automation systems and appliances may be directly connected to the cloud as distinct objects and as a result avoid protocol conversion

3.1.1 Project Scope

As mentioned the proposed home automation system consists of three main modules, the server, the hardware interface module, and the software package.As shown in figer. Serial port used by server and hardware interface module to communicate with each other. User may use the Internet to login to the server web based application., so remote users can access server web based application through the internet using compatible web browser. The system is designed keeping in mind the following key requirements:

3.1.2 User Classes and Characteristics The proposed home automation system is designed as a tool for the casual user. A casual user; shall be defined as one possessing general knowledge of the Microsoft Windows operating system and general knowledge of using the Internet by employing a standard browser such as Microsoft Internet Explorer General user; who will have the most use of the system functionality. Administrator; who will control the access and permissions policy of the system, and can add and delete user accounts, anything that a general user can perform, the administrator can also perform.

3.1.4 Design and Implementation Constraints The Proposed home automation system is implemented using JSP, HTML and CSS. The server application is implemented in jsp and java , and the embedded hardware interface application shall be implemented using C Processing Language. Software design concept Software of the proposed home automation system is divided to server application software, and Microcontroller (Arduino) firmware.

The server application software package for the proposed home automation system, is a web based application built using JSP ,java Netbeans IDE application software runs on windows OS, requires Glass Fish server, and JVM being installed. The server application software can be accessed from internal network or from internet if the server has real IP on the internet using any internet navigator supports jsp technology. Server application software is responsible of setup, configuration, maintain the whole home automation system. Server use database to keep log of home automation system components, we choose to use XML files to save system log. The Arduino software, built using C language, using IDE comes with the microcontroller itself. Arduino software is responsible for collecting events from connected sensors, then apply action to actuators and pre-programed in the server. Another job is to report the and record the history in the server DB.  Clients should be able to quickly and seamlessly connect to and disconnect from the system  Change in the status of an appliance should be propagated to all Clients in real-time.  Customizable time-based profiles to automatically activate and Deactivate appliances based on the time of day  Hardware should be widely compatible with different PC configurations.  Server should run in the background without disturbing regular activities on the desktop PC  Provide a simple and user-friendly interface on the client side. 3.1.5 Assumptions and Dependencies  The component of the system will always be connected  Each User must have a User ID and password  There is only one Administrator.  Server must always run under windows system  There should be Internet connection available.  Proper browsers should be installed  Proper Hardware Components are available  User is capable of using a computer

3.3 External Interface Requirement. 3.3.1 User Interfaces The primary goals of the home automation system user interfaces are accessibility, universality and reachability.The user interface is comprised of input and output devices. The input devices shall have the following components:  Touch Screen: The touch screen interface must be unscrachable, finger controllable and multi touchable.  Mobile Device: The mobile device interface must be small,attachable,and Compatible across different device

3.3.2 Hardware Interfaces Basically Home Automation System has a physical USB interface to get data and actuators to give a physical service. To handle getting data and make a service, HAM has a main computer called Home servers and to provide an user interface Sensors:  Smoke, thermal, CO-detector: These sensors detect fire. Actuators:  Light switch: Based on user location and behavior, light system can be smart.The system turn on/off lights through the light switch.  Alarm: if system detects safety, security or emergency situation the system alert it through the audible and visible alarm actuators. 3.3.3 Software Interfaces The system should use an xml file format for communication with rest of the home

3.3.4 Communication Interfaces

 The system shall be connected to internet.  The system has a connection with an emergency protocol which is conned to a hospital, police and fire station.

3.6 Analysis Models
DESIGN DIAGRAMS

Data Flow Diagrams:

The mobile device connects to the server PC through through the internet. The user sends commands to the server from the mobile device. The microcontroller is connected to the server via USB. On receiving commands from the mobile device, the server sends commands to the microcontroller over the USB connection. The microcontroller is directly connected to the relays and it can

enable or disable them. The relays are connected to the electrical system of the building so that they can control the plug points.

SEQUENCE DIAGRAMS

USE CASE DIAGRAMS

The server module receives control commands either from clients or directly from its own interface. The time-based profiles are configured on the server interface. It internally checks whether it’s time to activate a time-based profile. It propagates the status of the appliances to all connected clients

The client interface allows the user to control the appliances. It receives status updates from the server.

The microcontroller only receives commands from the server via USB

The component diagram shows all the physical components of the entire system and how they are interfaced with each other

3.7 System Implementation Plan The system is comprised of five different modules in total; three of which are client modules for different platforms.  Cloud server  Embedded Program for Microcontroller, and Hardware Circuit  Internet Client for any mobile phones or desktop

4. System Design: 4.1. System Architecture:

5. Technical Specification: This system consists of three independently developed sub systems. Different technologies were used in developing each sub system. These sub systems are; • Client application. • Central Server (Cloud Server) • Home System (communicating with hardware) Client application: The main objective of the Client application is providing user the basic interface to communicate with the home. It provides an illustrative view of the home and status of equipments and lets the user control them and closely monitor them with ease. In addition to that it sends alerts when there’s a change in the status of equipments or in the environment being monitored. There were two possible approaches for implementing the Client application. They are 1. Device based application: As we know that there are many devices available in market with different platform so develop and client application for every platform is not possible .for example consider a android and windows base devices so to actually enable or client to communicate with home automation system application should support both the platform. 2. Web based application: web application can be accessed through any platform using any browser interface and as we are using cloud server for home automation web application will help connecting any client from any platform Central Server (Cloud Server) The central server is focused in providing services to the other three modules. Central server acts as the brain and data repository of the system. It provides three interfaces to the three sub modules; mobile, web configuration tool and home system. The server analyzes the data it receives from home and send updates to the mobile and vice versa. At the same time it takes intelligent decisions about each system, such as whether there’s a failure in the home system and informs the user. A database is maintained by the server and it is updated according to the changes in the home. Since this acts as the heart of the entire system, careful analysis was needed before implementing this system.

During this analysis it was identified that implementing services on top of an existing server is more appropriate and efficient than developing the entire server from the scratch. Hence when implementing this subsystem, it was necessary to decide on three major components. They are • The database • Server • Scripting language to define services • Communication mechanism between the server and the other components Several tools and technologies available for the implementation of each component were carefully analyzed when selecting the most appropriate methodology. 11 The Glassfish server was selected as the most suitable server due to several reasons. One major reason is its high reliability and ability to handle a very large number of simultaneous requests without a failure. And also it is free software thus results in reducing the cost of this system. MySQL database is selected as the database of this system. Since mysql server is freely available and it’s supported with WAMP, it is identified as the most suitable database for this application. This will result in reducing the cost of system further while maintaining the quality of the product unharmed. Similarly JSP is selected as the scripting language and with the use of JSP the services were defined. Since JSP scripts run very fast and time is a critical factor for a system like this it is selected over the other scripting languages. Cloud computing is often defined as a large-scale distributed computing paradigm that is driven by economies of scale (reductions in unit cost as the magnitude of usage levels increase), in which a pool of abstracted, virtualized, Dynamically scalable, managed computing power, storage, platforms, and services are delivered on demand to users or customers, over the Internet . Classification of cloud services: 1. Software as a Service SaaS is a software delivery model in which application software are hosted by a service provider or vendor and made accessible to clients over a network, usually the Internet. Software as a service is becoming the dominant software distribution model as core technologies that support web services mature and the use of new developmental methodologies (like HTML5 and AJAX) become widespread. Correspondingly, expansion of broadband services to more areas facilitates user access from around the world.

2.Platform as a Service PaaS is a method to outsource computer hardware, operating systems, data storage and network bandwidthover a network, usually the Internet. PaaS distribution model permits the customer to rent virtualized servers and accompanying services to run application software or develop and evaluate new applications.PaaS is an extension of Software as a service, and offers numerous benefits for developers and designers. 3. Infrastructure as a Service: IaaS is a delivery model in which a business or institute leases the tools used to undertake certain tasks, including computer hardware, data storage, networking hardware and network bandwidth. The vendor possesses the equipment and is responsible for operation and maintenance.

Home System (communicating with hardware): The home system mainly consists of two parts. Main controller of the home is one end. This Main controller works between the central server and equipments which are fixed at the home. Other ends of the home system are a set of controllers which enable network level access to gadgets and the Main controller. The main objective of the home system is to provide the user with a convenient interface to configure the equipments. And also it acts as the communication base in user’s home. This lets the user add or remove equipments to the system with ease while communicating status changes in home with the central server and responding to requests send by the central server. Hence this system facilitates in improving the extensibility of the system. When designing home system initially there were two options available. They are; • Implementing it as a standalone application • Implementing it as a web application Security is the major concern of this system and it is very important preserve the confidentiality of the equipments being added to the system by each user. The home system is used during the installation phase of the system and when communicating the changes of home equipments to the server thereafter. Therefore it was identified that it is more convenient and secure to provide a standalone application. This application needs to run in the home computer and poll the central server at a constant rate. Therefore this system

should be implemented in a technology which is independent of the platform running in user’s home computer. Hence Java was selected as the most suitable programming language of this system. The home system acts as a mediator between the server and equipments at home. Thus the home system needs to be linked to the server as well as the equipments at home. There exists several possible media for the communication between the home system and equipments. Hence it is very important to identify the features of them and select the most appropriate medium. They can be categorized as wired and wireless media. Wireless media are discussed in former sections of this chapter. The wired media are discussed below. 1. Communication via the serial port In computing, a serial port is a serial communication physical interface through which information transfers in or out one bit at a time. But in most of the occasions only one of the equipments can be controlled through this mechanism. This is a major weakness in serial port communication. Another limitation of this mechanism is the requirement to connect a hardware device to the other end in orderto synchronizes the communication. This is another drawback in serial port communication. 2. Communication via the parallel port This is similar to the serial port but this mechanism does not require additional hardware for the synchronization of communication because data sent through these ports are already synchronized. But there is a limitation on the number of equipments that can be connected to this port. And also the parallel ports cannot tolerate uncontrolled inputs. This is another major weakness of this mechanism. 3. Communication via the network In this mechanism communication is done via the network with the use of network cables and a switch. This medium is accurate since equipments can be distinguished with unique ip addresses assigned to them and also it does not impose any limitation on the number of equipments that can be connected. Though this mechanism requires wiring of equipments to the home computer this can be avoided with the use of Ethernet over power (EOP) mechanism. Power line Ethernet runs over residential power lines using a Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) protocol to arbitrate the shared medium; a Physical layer designed for transmission over electrical wiring. Hence with the use of this mechanism it is possible to avoid wiring of equipments to the home system. Device to map controlling signal

The Arduino Uno is a microcontroller board based on the ATmega328 . It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz ceramic resonator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started.The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega16U2 (Atmega8U2 up to version R2) programmed as a USB-to-serial converter.


 

1.0 pinout: added SDA and SCL pins that are near to the AREF pin and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board. In future, shields will be compatible with both the board that uses the AVR, which operates with 5V and with the Arduino Due that operates with 3.3V. The second one is a not connected pin, that is reserved for future purposes. Stronger RESET circuit. Atmega 16U2 replace the 8U2.

"Uno" means one in Italian and is named to mark the upcoming release of Arduino 1.0. The Uno and version 1.0 will be the reference versions of Arduino, moving forward. Summary: Microcontroller ATmega328 Operating Voltage 5V Input Voltage 7-12V (recommended) Input Voltage (limits) 6-20V Digital I/O Pins 14 (of which 6 provide PWM output) Analog Input Pins 6 DC Current per I/O Pin 40 mA DC Current for 3.3V Pin 50 mA 32 KB (ATmega328) of which 0.5 KB used by Flash Memory bootloader SRAM 2 KB (ATmega328) EEPROM 1 KB (ATmega328) Clock Speed 16 MHz

Power The Arduino Uno can be powered via the USB connection or with an external power supply. The power source is selected automatically.External (non-USB) power can come either from an AC-to-DC adapter (wall-wart) or battery. The adapter can be connected by plugging a 2.1mm center-positive plug into the board's power jack. Leads from a battery can be inserted in the Gnd and Vin pin headers of the POWER connector. The board can operate on an external supply of 6 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts. The power pins are as follows:


VIN. The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power



  

source). You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin. 5V.This pin outputs a regulated 5V from the regulator on the board. The board can be supplied with power either from the DC power jack (7 - 12V), the USB connector (5V), or the VIN pin of the board (7-12V). Supplying voltage via the 5V or 3.3V pins bypasses the regulator, and can damage your board. We don't advise it. 3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA. GND. Ground pins. IOREF. This pin on the Arduino board provides the voltage reference with which the microcontroller operates. A properly configured shield can read the IOREF pin voltage and select the appropriate power source or enable voltage translators on the outputs for working with the 5V or 3.3V. Memory The ATmega328 has 32 KB (with 0.5 KB used for the bootloader). It also has 2 KB of SRAM and 1 KB of EEPROM (which can be read and written with the EEPROM library). Input and Output Each of the 14 digital pins on the Uno can be used as an input or output, using pinMode(), digitalWrite(), and digitalRead()functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions:





 

Serial: 0 (RX) and 1 (TX). Used to receive (RX) and transmit (TX) TTL serial data. These pins are connected to the corresponding pins of the ATmega8U2 USB-toTTL Serial chip. External Interrupts: 2 and 3. These pins can be configured to trigger an interrupt on a low value, a rising or falling edge, or a change in value. See the attachInterrupt() function for details. PWM: 3, 5, 6, 9, 10, and 11. Provide 8-bit PWM output with the analogWrite() function. SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK). These pins support SPI communication using the SPI library.



LED: 13. There is a built-in LED connected to digital pin 13. When the pin is HIGH value, the LED is on, when the pin is LOW, it's off. The Uno has 6 analog inputs, labeled A0 through A5, each of which provide 10 bits of resolution (i.e. 1024 different values). By default they measure from ground to 5 volts, though is it possible to change the upper end of their range using the AREF pin and the analogReference() function. Additionally, some pins have specialized functionality:



TWI: A4 or SDA pin and A5 or SCL pin. Support TWI communication using the Wire library There are a couple of other pins on the board:

 

AREF. Reference voltage for the analog inputs. Used with analogReference(). Reset. Bring this line LOW to reset the microcontroller. Typically used to add a reset button to shields which block the one on the board. See also the mapping between Arduino pins and ATmega328 ports. The mapping for the Atmega8, 168, and 328 is identical. Communication The Arduino Uno has a number of facilities for communicating with a computer, another Arduino, or other microcontrollers. The ATmega328 provides UART TTL (5V) serial communication, which is available on digital pins 0 (RX) and 1 (TX). An ATmega16U2 on the board channels this serial communication over USB and appears as a virtual com port to software on the computer. The '16U2 firmware uses the standard USB COM drivers, and no external driver is needed. However, on Windows, a .inf file is required. The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Arduino board. The RX and TX LEDs on the board will flash when data is being transmitted via the USB-to-serial chip and USB connection to the computer (but not for serial communication on pins 0 and 1). A SoftwareSerial library allows for serial communication on any of the Uno's digital pins. The ATmega328 also supports I2C (TWI) and SPI communication. The Arduino software includes a Wire library to simplify use of the I2C bus; see the documentation for details. For SPI communication, use the SPI library.

Programming The Arduino Uno can be programmed with the Arduino software (download). Select "Arduino Uno from the Tools > Board menu (according to the microcontroller on your board). For details, see the reference and tutorials. The ATmega328 on the Arduino Uno comes preburned with a bootloader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the original STK500 protocol (reference, C header files). You can also bypass the bootloader and program the microcontroller through the ICSP (In-Circuit Serial Programming) header; see these instructions for details. The ATmega16U2 (or 8U2 in the rev1 and rev2 boards) firmware source code is available . The ATmega16U2/8U2 is loaded with a DFU bootloader, which can be activated by:
 

On Rev1 boards: connecting the solder jumper on the back of the board (near the map of Italy) and then resetting the 8U2. On Rev2 or later boards: there is a resistor that pulling the 8U2/16U2 HWB line to ground, making it easier to put into DFU mode. You can then use Atmel's FLIP software (Windows) or the DFU programmer (Mac OS X and Linux) to load a new firmware. Or you can use the ISP header with an external programmer (overwriting the DFU bootloader). See this usercontributed tutorial for more information. Automatic (Software) Reset Rather than requiring a physical press of the reset button before an upload, the Arduino Uno is designed in a way that allows it to be reset by software running on a connected computer. One of the hardware flow control lines (DTR) of theATmega8U2/16U2 is connected to the reset line of the ATmega328 via a 100 nanofarad capacitor. When this line is asserted (taken low), the reset line drops long enough to reset the chip. The Arduino software uses this capability to allow you to upload code by simply pressing the upload button in the Arduino environment. This means that the bootloader can have a shorter timeout, as the lowering of DTR can be well-coordinated with the start of the upload. This setup has other implications. When the Uno is connected to either a computer running Mac OS X or Linux, it resets each time a connection is made to it from software (via USB). For the following half-second or so, the bootloader is running on the Uno. While it is programmed to ignore malformed data (i.e.

anything besides an upload of new code), it will intercept the first few bytes of data sent to the board after a connection is opened. If a sketch running on the board receives one-time configuration or other data when it first starts, make sure that the software with which it communicates waits a second after opening the connection and before sending this data. The Uno contains a trace that can be cut to disable the auto-reset. The pads on either side of the trace can be soldered together to re-enable it. It's labeled "RESET-EN". You may also be able to disable the auto-reset by connecting a 110 ohm resistor from 5V to the reset line; see this forum thread for details. USB Over current Protection The Arduino Uno has a resettable polyfuse that protects your computer's USB ports from shorts and overcurrent. Although most computers provide their own internal protection, the fuse provides an extra layer of protection. If more than 500 mA is applied to the USB port, the fuse will automatically break the connection until the short or overload is removed.

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