In newer construction or recently renovated houses you may find Ground Fault Circuit Interrupters in some outlets. They're also called GFCI's for short. GFCI outlets have the two buttons in the middle that are marked test and reset A Ground Fault Circuit Interrupter is an electronic device that will trip or turn off the circuit when it senses a potentially hazardous condition. It's very sensitive and operates very quickly. The GFCI will interrupt the power in less than 1/50 of a second if it senses an imbalance in the electrical current of as little as 0.005 amps. The quick response time in interrupting the power is fast enough to prevent injury to anyone in normal health. The GFCI senses the current flow between the hot and neutral conductor in a circuit. Since the human heart begins to fibrillation (beat rapidly and irregularly) at about five milliamperes, the likelihood of electrocution is greatly reduced.
The National Electric Code recommends that Ground Fault Circuit Interrupter's be installed anywhere near water for safety. Water prone areas include basements, garages, kitchens, bathrooms and all exterior outlets.
The National Electric Code recommends that Ground Fault Circuit Interrupter's be installed anywhere near water for safety. Water prone areas include basements, garages, kitchens, bathrooms and all exterior outlets. You should recommend the installation of GFCI's to all of your clients for safety reasons. They're generally an inexpensive item to have installed and they significantly increase electrical safety in the home.
All GFCI circuit breakers, switches and receptacles should be tested to see if the fault sensing function is operating. Test them by pressing the button marked test. If the ground fault sensing device is operating properly, you'll hear a click and the reset button will pop out. This should cut off the electrical current to that outlet.
Many hand held electrical outlet testers have GFCI testing devices on them. Sometimes the hand held testers cannot trip the GFCI but the test and reset buttons on the outlet will work. If this happens, then the Ground Fault Circuit Interrupter may not be operating properly. Notify the client and the homeowner if the GFCI isn't operating properly and recommend it be repaired.
Generally, an outlet GFCI only monitors that one particular outlet it's located in. However, some GFCI's monitor more than one outlet. For example, there may be a Ground Fault Circuit Interrupter outlet in one bathroom that will monitor the outlet in another bathroom as well. This is because both outlets are on the same branch line. Also, some GFCI's are installed directly in the circuit breaker in the main electrical panel. The benefit of installing a GFCI in the circuit breaker of the main panel is that the ground fault sensing device will monitor all of the outlets and switches on that particular branch line. There is a drawback to this type of installation. Since GFCI's are so sensitive, often they'll go off without someone being electrocuted. If the reset button is located in a circuit breaker in the main panel the homeowner must go to the main panel to reset the outlet. If the reset button is located in the outlet the homeowner can reset the outlet more conveniently.
If there are any Ground Fault Circuit Interrupter's in the circuit breakers of the main electrical panel, ask the homeowner if you can test them. Do not test these breakers before checking with the owner. You never know what that GFCI is supplying. It could be supplying electricity to an appliance or outlet that must not be shut off. So check with the owner before testing any GFCI's. When a GFCI circuit breaker is tripped off, it has to be reset properly to turn the power back on. A GFCI breaker may stay in the middle position after being tripped. The way to reset the breaker is to first push the handle so it's all the way off. Then push the handle back to the on position and electric power should be restored.
The NEC recommends that houses have an outlet for every six feet of horizontal wall space. This is because most appliances come with six foot electrical cords and if there aren't enough outlets, then the homeowner must use extension cords. Many older houses won't have enough outlets so check for any extension cords in use. Some older houses don't have outlets in the bathrooms which is an inconvenience. Extension cord wiring isn't recommended because of the possibility of someone plugging an appliance into an extension cord that has a low amperage rating. This will cause the extension cord wire to overheat and start an electrical fire. Warn your client about the use of any extension cord wiring.
If the client has children recommend that they install child proof caps for the electrical outlets. These are small plastic plugs to cover any unused outlets so a child won't stick anything into them and get electrocuted. You should also recommend that they use child guards for all cabinets to prevent children from opening cabinets that have cleansers and sharp objects inside.
Sometimes a client might ask you about aluminum wiring in the house. There have been fires in the past that were attributed to aluminum branch wiring in structures. Aluminum wiring is apparently less expensive to install than copper wiring. It was used a lot more during the 1970's when the price of copper became very expensive. The reason for these fires was aluminum wiring heats faster and hotter than copper wiring when electricity passes through it. It also cools down quicker than copper wiring when the current is shut off. When electrical wires heat up and cool down, they expand and contract, just like anything else. The problem of aluminum wiring was with branch circuits below 40 amperage ratings. These thinner gauge wires would expand and contract until the wires came loose from the electrical outlets, switches and circuit breaker screws. Once they would come loose they could touch the wooden wall studs or other combustible items and start an electrical fire.
The way to prevent this problem is to use only copper wires for any branch circuits below 40 amps. Also, all aluminum wiring, whether it is above or below 40 amps, must be used with aluminum rated adaptors, connections, outlets, switches, etc. The specially marked adaptors will have aluminum contacts instead of copper. This will prevent any oxidation of the nonmatching metals that could cause deterioration problems.
There are also chemicals on the market that should be put on the ends of the aluminum wires before they're attached to any connections or adaptors. These chemicals will help prevent oxidation of the wires. Some of the manufacturer name brands for these chemicals are Penetr-Ox and Anti-Ox. It's similar to using mixed material plumbing lines. Where the two different metals meet, there will be an oxidation problem that will deteriorate the lines at the point of the connection.