Working with electricity is daunting at first. It's easy to think, "I have no idea how this works, and I'll probably get shocked." And nobody with an ounce of common sense would think otherwise. Electricity is dangerous and can shock or even kill you. But electricity is predictable and obeys certain rules as well. An electrical system, such as home wiring, can be modified, repaired or upgraded because the same action in the same circumstance will always produce the same result. The electricity delivered to our homes must conform to a set of standards. Appliances and fixtures must as well. With the help of a few facts and rules of thumb, the average homeowner can tackle a range of common household wiring jobs.
Once a connection is made between a power grid and a house, electricity runs from a circuit breaker or fuse box through the house and back to the box. This configuration is called a circuit and requires three wires: a hot wire (black), a neutral wire (white) and a ground wire (bare copper). Sometimes a second hot wire (red) is built in as well. A circuit works only if it's uninterrupted.
For example, imagine creating a simple circuit to run a single light. A black wire runs from the power main (circuit breaker or fuse box) to a lightbulb. A white wire then runs from the lightbulb to the neutral bus of the power main. The ground wire runs from the main to the lightbulb.
The black and white wires can be thought of as a single wire with regular interruptions to feed outlets, fixtures, appliances, etc. The lightbulb will remain on as long as there is power. However, if we add a switch along the black wire, we can turn the light on and off as we like. A switch is just a way of interrupting or connecting power to a device.
In How to Install a Motion-Sensing Light Switch, you will find a step-by-step guide to one of the simplest (and most cost-effective) home wiring tasks. Before making any wiring changes, be sure to turn off the circuit in your fuse box and study the wiring that you see in your walls to be sure you understand how the circuit works and which wire is the hot wire, which the neutral wire and which the ground. If you are unclear about anything you are seeing, STOP and consider the logic of the wiring again. If you still can't see how the circuit works, call an electrician. The electrician can help you understand how your home's wiring works, so ask questions.
- Bisphenol A (BPA)
- Hexavalent Chromium
- Methylene chloride (dichloromethane)
- Perchloroethylene (Tetrachloroethylene, PERC, PCE)
- Propoxur (Flea and Tick Pesticide)
- Sulfur Dioxide
- TDCP/TCEP (Chlorinated Flame Retardants)
- Tetrachlorvinphos (Flea and Tick Pesticide)
- Trichloroethylene (TCE)
- Triclosan and Triclocarban (Antibacterials)