In order to avoid confusion and to encourage harmony, Amendment 2 of the 17th Edition BS7671 Wiring Regulations brought a change in the UK wiring colours and made it as the European wiring colours in 2006. This was also done to promote the business of electrical goods and to have compatibility in electrician’s qualifications in the UK and the mainland.
Let’s talk about the British wiring colours as they are now.
British Wiring Colours—Why Use Different Colours In The First Place?
If we consider the theory, an electrical appliance requires one wire to bring electricity to it. Imagine cutting the wire in half and connecting the electrical appliance in the middle. One wire brings electricity to the appliance, while the other takes it away. These are known as live and neutral wires respectively. These are your two wires, but what about the last one? The third wire is for safety precautions and is known as the earth wire. In order to reduce the chances of electrocution and house fires, the earth wire provides a connection to the earth at all times.
It is not just the residential buildings that have three-coloured wires in the UK, but there are three colours inside the actual appliance as well. This offers consistency when you work on various appliances with the appliance wiring colours the same as the plug wiring colours.
UK Wiring Colours – A Guide
Before we talk about the new wiring schemes in British, let’s state the old wiring colours just so you could have a little perspective.
In the UK, all the domestic electrical plugs had three colours: red, black, and green showcasing yellow stripes.
The colour of the live wire had been red.
The neutral wire used to be in the colour black.
Green With Yellow Stripes
The wire for earth used to be green before the year 1977. After that, it changed to green and yellow and is the same ever since.