Electric wire color coding

by Shirley Williams
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If you don’t know what the color of each electrical wire means then we strongly recommend you stay away from doing any electric works in the home. However, if you just want to change a socket then it does seem silly to call an electrician for such a simple job. If you have a little common sense and the job is straight forward, you will be able to do it alone. Here is what each color wire means.

The first and most important thing is that if you decide to play with wires you must turn off the power at the circuit board. This means that you will at least avoid an electric shock while working on the wires. The colors themselves are important so don’t think you can join one color wire to another as you see fit. There is a very special relationship involved in it all.

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Thomas Edison introduced the electric lamp in 1879, he did not have a color-coding system in place back then. It would take until 1928 until someone thought it was a good idea to put a system in place for the colors of wires. A new edition of the National Electrical Code was released in America and it contained guidelines for colors. The code did not go into great detail but suggested that ground wires should be white or natural grey to distinguish them from all others. In 1937 the governing body got around to classifying colors for other wires with three branch circuits supposed to have a black wire, a red wire, and a white wire. 

As time went on the colors for wires continued to change with green being introduced as a possible ground wire in the 1950s. By the 1970s the governing body was clearly frustrated and actually decided to eliminate all rules for wire colors that were not grounded. They said there were simply too many possibilities. Instead, they simply had a range of colors for ground wires and everything else could be anything else. 

Fast forward to today and while there is a set of rules in place it differs from country to country. Ground wires in America must be one of green, green and yellow striped, or bare. Neutral wires should be white or gray. Circuit wire colors change depending on the voltage they emit and range from yellow, orange, blue, brown, red, and black.

In other countries, colors do vary slightly. In Ireland, for example, neutral must be blue or black, live must be brown or red, and the earth wire must be green or yellow. It is important to double-check the wires in your country to ensure you know which one is the earth wire. The earth wire is incredibly important and you should know which one it is. A device will work without the earth wire because it is not part of the conducting path that is supplying electricity to the device. However, the earth wire is what protects you from an electric shock. It provides a path for a fault current to flow to earth. It also tells the circuit breaker or fuse to stop the electric current to the circuit that has a fault. Remember that loose wires are what cause most fires so ensure that any fittings you do are connected well. If you do smell any burning make sure you turn everything off and call an electrician.

The colors are interesting when it comes to wiring sockets. Once you know the different colors for the earth, live and neutral wires you are able to change a socket in your home without the need to pay a lot for an electrician. However, if you have any doubts it is always better to get a professional.

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