ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

How a Faraday Cage Works

Updated on August 26, 2014

The Basic Concepts of a Faraday Cage are Illustrated Here

There are many ways to make a Faraday cage for a broad range of reasons. If you work with substantial amounts of electromotive and inductive electrical forces, some form of this is manditory.
There are many ways to make a Faraday cage for a broad range of reasons. If you work with substantial amounts of electromotive and inductive electrical forces, some form of this is manditory. | Source
For those of us who need a blueprint, this illustration should give a basic idea of how to make a Faraday cage. Just remember to add the grounding circuit when done and it is in use.
For those of us who need a blueprint, this illustration should give a basic idea of how to make a Faraday cage. Just remember to add the grounding circuit when done and it is in use. | Source

The Faraday Cage and Like Ideas are in Common Use Today

A Faraday Cage is named after the discoverer of the principle, Michael Faraday, who described induction where electrical energy can be guided by a conductive substance like copper, aluminium or steel when excited by a magnetic force. To sum up his law on induction; The EMF (electromotive force) generated is proportional to the rate of change of the magnetic flux” (1). But the Faraday cage today is different from the concept of a simple conductor, because it can be used to isolate sensitive electronic components from a power surge that could come from an electromagnetic pulse or from a lightning strike. Why is this so?

The short answer is that electric force results when opposite charges attempt to balance out into a neutral state. Electric force can build up due to friction as in electrostatics or from induction by a magnetic force. Nature always seeks a levelling of forces, which is why we can step in and tap energy in transition. Electrostatic and electrical-inductive force comes in positive and negative aspects. When there is a surplus of one type or the other, the tendency is for dispersal. Electricians are familiar with the tendency of high voltage to disperse away from a conductor and thus can wear a conductive covering to allow the high voltage a path away from the body when working on high voltage circuits. The Faraday cage works in a similar manner by being an antenna and ground for high voltage or induction surge that comes from an electromagnetic pulse (EMP).

A typical Faraday cage is constructed so that it shields ether buildings from high voltage strikes, or the human body when working with high tension voltage or sensitive electronics from sudden EMP induction that can literally explode sensitive microelectronic circuits. They are essentially a hollow antenna that “picks up” over charges of electromotive or electrostatic force and dumps it into the ground, protecting anything that it surrounds.

This popular idea will protect your sensitive electronics in the event of an EMP strike

A high tension line worker has to wear a Faraday cage suit

It's Easy to Build a Faraday Cage

The construction of a Faraday cage is simple in the extreme. They can be made of any electrically conductive material, can be made up of mesh wire or solid sheet metal. There are ready made answers in the form of galvanized metal garbage cans complete with lids. Some can be lined with insulating material such as cardboard for extra protection for anything inside. As same charge electromotive or electrostatic charge tends to repel, the force will naturally flow away and around what is being protected via the enclosing hollow Faraday cage. The Faraday cage can be grounded with something as simple as an attached heavy duty wire that is connected to a conductor driven into the ground.

Thus, when lightning strikes, or there is an EMP event, the sudden power surge is carried around what is being protected and directed into the ground to disperse, much as lightning does anyway in nature. The difference is that the Faraday cage will protect anything inside from a direct lightning strike, whereas the unprotected item will absorb the full impact of the instantaneous power surge and be destroyed in the process. That being said, let us look at some videos on how to be protected from high voltage and sudden inductive currents by the use of a Faraday cage.




    0 of 8192 characters used
    Post Comment
    • profile image

      David M. 

      23 months ago

      Now i know why this doesnt work with microwave owen. The doors is not completely electrically connected all the way around the edge.

    • profile image


      7 years ago

      I enjoed your Hub. The video really helped to show a real world application.

    • em_saenz profile image


      7 years ago from Europe

      Thank you so much for answering my question and good luck in the contest.

    • profile image

      Jim Lenahan 

      7 years ago

      I have been searching for information on how to defend aginst the possible EMP and Solar Flare for months and finally a simple explanation for lay people. Thank you Jim

    • syzygyastro profile imageAUTHOR

      William J. Prest 

      7 years ago from Vancouver, Canada

      Cold dray weather is the worst. The air is dry and the temperature difference between an indoor heated space and sub zero outdoor temperatures is enough to really drive up the electrostatic potential. I've seen 1 to 2 inch sparks when I touch anything metallic on those days and it is quite a jolt.

    • chinese2learning profile image


      7 years ago from Beijing

      Interesting! During dry seasons, I am scared of touching any metal.


    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at:

    Show Details
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the or domains, for performance and efficiency reasons. (Privacy Policy)
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)
    ClickscoThis is a data management platform studying reader behavior (Privacy Policy)