GFCI Receptacles

The GFCI

A “GFCI” is a ground fault circuit interrupter.  A ground fault circuit interrupter is an inexpensive electrical device that, if installed in household branch circuits, could prevent over two-thirds of the approximately 300 electrocutions still occurring each year in and around the home.  Installation of the device could also prevent thousands of burn and electric shock injuries each year.

The GFCI is designed to protect people from severe of fatal electric shocks.  Because a GFCI detects ground faults, it can also prevent some electrical fires and reduce the severity of others by interrupting the flow of electric current.

The Problem

Have you ever experienced an electric shock?  If you did, the shock probably happened because your hand or some other part of your body contacted a source of electrical current and your body provided a path for the electrical current to go to the ground, so that you received a shock.

An unintentional electric path between a source of current and a grounded surface is referred to as a “ground-fault.”

Ground Faults

Ground faults occur when current is leaking somewhere, in effect, electricity is escaping to the ground.  How it leaks is very important.  If your body provides a path to the ground for this leakage, you could be injured, burned, severely shocked, or electrocuted.

Some examples of accidents of this nature include: five and six year old children in Texas being fatally electrocuted when a plugged-in hair dryer fell into the tub while they were bathing; a three-year old child in Kansas being fatally electrocuted when she touched a faulty counter top.

These two electrocutions occurred because the electrical current escaping from the appliance traveled through the victim to ground (in these cases, the grounded plumbing fixtures).  Had a GFCI been installed, these deaths would probably have been prevented because a GFCI would have sensed the current flowing to ground and would have switched off the the power before the electrocution occurred.

How the GFCI works

In the home’s wiring system, the GFCI constantly monitors electricity flowing in a circuit to sense any loss of current.  If the current flowing through the circuit differs by a small amount from that returning, the GFCI quickly switches off to that circuit.  The GFCI interrupts power faster than a blink of an eye to prevent a lethal dose of electricity.  You may receive a painful shock, but you should not be electrocuted or receive a serious shock injury.

Suppose a bare wire inside an appliance touches the metal case.  The case is then charged with electricity.  If you touch the appliance with one hand while the other hand is touching a grounded metal object, like a water faucet, you will receive a shock.  If the appliance is plugged into an outlet protected by a GFCI, the power will be shut off before a fatal shock would occur.

Availability of GFCI’s

Three common types of ground fault circuit interrupters are available for home use

  1. Receptacle type–This type of GFCI is used in place of the standard duplex receptacle found throughout the house.  It fits into the standard outlet box and protects you against “ground faults” whenever an electrical product is plugged into the outlet.  Most receptacle-type GFCI’s can be installed so that they also protect other electrical outlets further “down stream” in the branch circuit.
  2. Circuit breaker type–In homes equipped with circuit breakers rather than fuses, a circuit breaker GFCI may be installed in a panel box to give protection to selected circuits.  The circuit breaker GFCI serves a dual purpose – not only will it shut off electricity in the even of a “ground-fault,” but it will also trip when a short circuit or an over-load occurs.  Protection covers the wiring and each outlet, lighting fixture, heater, etc. served by the branch circuit protected by the GFCI in the panel box.
  3. Portable type–Where permanent GFCI’s are not practical, portable GFCI’s may be used.  One type contains the GFCI circuitry in a plastic enclosure with plug blades in the back and receptacle slots in the front.  It can be plugged into a receptacle then the electrical product is plugged into the GFCI.  Another type of portable GFCI is an extension cord combined with a GFCI.  It adds flexibility in using  receptacles that are not protected by GFCI’s.

Where Should GFCI’s Be Installed?

In homes built to comply with the National Electrical Code, GFCI protection is required for most outdoor receptacles, bathroom receptacle circuits, garage wall outlets, kitchen receptacles, and all receptacles in crawl spaces and unfinished basements.

Owners of homes that do not have GFCI’s installed in all of those critical areas specified in the latest version of the Code should have them installed and brought up to code.  For broad protection, GFCI circuit breakers may be added in many panels of older homes to replace ordinary circuit breakers.  For homes protected by fuses, you are limited to receptacle or portable-type GFCI’s and these may be installed in areas of greatest exposure such as the bathroom, kitchen, basement, garage, and outdoor circuits.

A GFCI should be used whenever operating electrically powered garden equipment (lawn mower, hedge trimmer, edger, etc.).  Consumers can obtain similar protection by using GFCI’s with electric tools (drills, saws, sanders, etc.) for do-it-yourself work in and around the house.

Installing GFCI’s

Circuit breaker and receptacle-type GFCI’s may be installed in your home by a qualified, licensed electrician.  Receptacle-type GFCI’s may be installed by knowledgeable consumers familiar with electrical wiring practices who also follow the instructions accompanying the device.  When in doubt about the proper procedure, contact a licensed electrician.  DO NOT INSTALL IT YOURSELF!

Testing the GFCI’s

All GFCI’s should be tested once a month to make sure they are working properly and protecting you from fatal shock.  GFCI’s should be tested after installation to make sure they are working properly and protecting the circuit.

To test the receptacle GFCI, first plug a nightlight or lamp into the outlet.  The light should be on.  Then press the “TEST” button on the GFCI.  The GFCI’s “RESET” button should pop out and the light should go out.

If the “RESET” button pops out but the light does not go out, the GFCI has been improperly wired.  Contact an electrician immediately to correct the wiring errors.

If the “RESET” button does not pop out, the GFCI is defective and should be immediately replaced.

If the GFCI is functioning properly, and the lamp goes out, press the “RESET” button to restore power to the outlet.

Add to Del.cio.us RSS Feed Add to Technorati Favorites Stumble It!
   www.sajithmr.com

Comments

One Response to “GFCI Receptacles”

  1. DANNY on September 7th, 2010 2:36 pm


    CheapTabletsOnline.Com. Canadian Health&Care.Best quality drugs.Special Internet Prices.No prescription online pharmacy. Low price pills. Buy drugs online

    Buy:Zovirax.Nexium.Petcam (Metacam) Oral Suspension.Prevacid.Retin-A.Arimidex.Synthroid.Zyban.Mega Hoodia.Lumigan.Actos.Accutane.Valtrex.100% Pure Okinawan Coral Calcium.Prednisolone.Human Growth Hormone….

Leave a Reply