The breakers or fuses serve two functions: They protect the wires against overheating in the event that they are overloaded by too much electrical current being drawn through them; they also sense short circuits and trip or "blow" to instantly stop the flow of current when problems occur. In a short circuit or ground fault situation, a sudden reduction in resistance causes an uncontrollable amount of current to flow, and the circuit breaker responds to this by tripping. Finally, it is fairly common practice for the metal plumbing pipes in your home to also be connected to the grounding pathway.
This offers additional protection should electricity come in contact with these metal pipes. Often, this grounding is established by a grounding wire clamped to a metal water pipe near your water heater or where the public water line enters your home. Not only does your home wiring system have a grounding system for safety, but many plug-in appliances and devices do, too. Power tools, vacuums, and many other appliances are much safer when they have a third prong on the cord plug, which is shaped to fit the round grounding slot on an outlet receptacle.
The presence of this third prong indicates that the appliance has a grounding system, and it is essential that these be plugged into grounded outlets. Some people have been known to cut off the grounding prong on an appliance plug in order to make it fit an outlet or extension cord that has no grounding slot. This is an extremely dangerous practice that could lead to a shock if the internal wiring in the appliance short circuits. Most people are familiar with the plug adapters than allow three-prong plugs to be inserted into two-slot outlet receptacles.
It is important to note that these offer grounding protection ONLY if the pigtail wire or metal loop on the adapter is properly attached to the mounting screw on the outlet cover plate, AND if that cover plate screw is connected to a metal box AND if that metal box is properly grounded.
This is no sure thing, by any means, so three-prong to two-slot adapters should be used with great caution, if at all. The better solution is to plug three-prong plugs only in into three-slot receptacles that are grounded. Where a grounded outlet is not possible, as in older wiring, some protection is offered by installing a GFCI ground-fault circuit interrupter receptacle at that location. The GFCI will sense ground faults and shut off the power before straying current can cause problems.
It's important to note, though, that using a GFCI does not actually create a grounding pathway; it merely makes an ungrounded outlet somewhat safer. Of course, not all appliances and plug-in devices have a three-prong grounded plug, and these are still safe to use since normally they have a double-insulated construction that minimizes the risk of short circuits. International Association for Fire Safety Science.
Occupational Safety and Health Administration, U. Department of Labor. Creative Pub. International , Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content. Want to know more about electrical safety? Check out this information about Electrical Safety Month from Mr. Skip to main content. Your health and safety are our highest priority during this time. Click here for our precautionary measures. Make sure your home is properly grounded — call Mr.
Electric at This blog is made available by Mr. Electric for educational purposes only to give the reader general information and a general understanding on the specific subject above. The blog should not be used as a substitute for a licensed electrical professional in your state or region. Check with city and state laws before performing any household project. If the wiring systems use electrical cables that are covered in metal, then the metal usually serves as the ground conductor between the wall outlets and the service panel.
However, if the wiring systems use a plastic-sheathed cable, then an extra wire is used for grounding. Electricity always looks for the shortest path to the earth, therefore if there is any problem where the neutral wire is broken or interrupted, it is the grounding wire that provides a direct path to the ground.
This direct physical connection allows the earth to act as a path of least resistance and prevent an appliance or a person from becoming the shortest path. You may experience power surges at times or you may be exposed to lightning during extreme weather conditions. These events may produce dangerously high electricity which can completely damage your electrical appliances. By grounding the electrical system, all the excess electricity will go into the earth instead of frying the appliances connected to the system.
The appliances will be safe and protected from large electrical surges. Stabilizes the Voltage Levels When you ground the electrical system, it makes it easier for you to distribute the right amount of power at the right places. This ensures that the circuits are not overloaded at any point and get blown as a result of it. The earth can be considered as a common reference point for the voltage sources in any electrical system.
This helps in providing stabilized voltage levels throughout the electric system. Earth Conducts with Least Resistance One of the main reasons why you should ground your electrical appliances is that the earth is a great conductor and it can conduct all the excess electricity with least resistance.
When you ground the electrical system and connect it to the earth, it means that you are giving the excess electricity to go somewhere without resistance rather than going through you or your appliances. Prevents Serious Damage and Death When you do not ground the electrical system, you will put your appliances and even your life at high risk.
When high electricity passes through any device, it will be fried and get damaged beyond repair. An excessive amount of electricity may even start a fire, putting your property and the life of your loved ones at risk. Determining if Current is Grounded or Not You can check if an electrical appliance is designed to be grounded or not. If the appliance is equipped with a three-wire cord and a three-pronged plug, then the third wire and prong will provide the ground link between the metal frame of the appliance and the grounding of the wiring system.
To check if the electrical system is grounded or not by checking your power outlets.
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