9 Things You Should Know About Your Home's Electrical System

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Your home electrical system is very important to the safety and well being of your entire family. The job of wiring a home is rigidly controlled by local code requirements and safety standards. In order to properly install an electrical system it is crucial to find a highly qualified electrical contractor to wire your home or to make changes to your current system.

1. Everyone who does electrical work needs a line tester—an indicator light with two leads. Keeping your fingers on the insulated portions of the tester, press the metal electrodes into a receptacle or touch them to the terminals you're testing. If the light comes on, there's power there.

2. Power from the utility comes in through your main service entrance, either in overhead or underground wires, and then to the meter that monitors your usage. From there it goes to your home's service panel, where it's broken down into a series of circuits. Circuit breakers or fuses at the panel control the individual circuits that take power throughout your home. They also protect against fire by turning a circuit off if it happens to get more current than it's designed to handle. And that's it.

3. Although these electrical projects are simple and straightforward, never cut corners where safety is concerned. Always turn off power to the circuit or device you're working on. That means removing the fuse or shutting off the circuit breaker at the main service panel. But that's not all. You still need to confirm that the power is off by testing the circuit with a neon circuit tester. Only then are you ready to start your project.

4. Telephone outlets, television jacks, and thermostat and doorbell wires are easiest to install while wiring new electrical circuits. Install the cables when the framing is exposed, making final connections after the walls are finished.

5. Telephone lines use four or six-wire cable-often called "bell wire"-while television lines use a shielded coaxial cable with threaded end fittings called "F-connectors." To splice into an existing television line, use a fitting called a signal splitter. Splitters are available with two, three, or four nipples. Coaxial cable can be difficult to strip.

6. Solid copper wires are the most efficient conductors of electricity. Be sure to use wires that are large enough for the amperage rating of the circuit. A wire that's too small may become dangerously hot.

7. Troubleshooting and replacing switches and outlets are among the most straightforward and simple do-it-yourself electrical projects you can tackle. When a switch or outlet blows a fuse, it's often an easy-to-spot loose wire touching the metal box that's the culprit. In the case of switches, when the mechanical moving parts wear out and fail, you can bird-dog the problem with your trusty continuity tester. And even if a switch or outlet isn't bad, you can add an extra measure of function or safety by replacing it with a specialty type, such as a dimmer switch or a ground-fault circuit-interrupter receptacle.

8. When you replace a wall switch (or an outlet), be sure the rating of the new device matches the circuit where it'll go. Specifically, look for two numbers -- the amperage rating and the voltage rating -- which you'll find stamped on the back or strap. Standard switches and outlets are rated at 15A and 125V (but voltage ratings of 100, 120, and 125 are considered to be one and the same).

9. There's no such thing as an all-purpose extension cord. The cord you need is the one that carries enough current to handle the needs of the appliance. If the wire's too thin, the current will overheat and damage the cord. It could even start a fire. If the cord's too long, it can waste power and cause a drop in voltage. Read the labels on your appliances.

Always shut off your home's circuit breaker before performing ANY electrical repairs in your home. If you are unfamiliar with your home electrical system, hire a profeessional. It is crucial to find a highly qualified electrical contractor to wire your home or to make changes to your current system.