Leaving the wires the same length usually results in the live and neutral wires becoming crushed when the plug cover is replaced. The plug is also designed so that the live (brown) is the shortest and tightest wire in the plug. (N) = Neutral = Blue. (E) = Earth = Yellow & Green.
Note: The Yellow/Green wire (Earth) needs to be slightly longer than the blue (Neutral) and Brown (Live) wires, in order to reach the top terminal. It is better to have the cables slightly longer than necessary and cut them to the correct length than try to stretch cables to make them reach the terminals.
Neutral is a circuit conductor that normally carries current back to the source. In the electrical trade, the conductor of a 2-wire circuit connected to the supply neutral point and earth ground is referred to as the "neutral".
The UK changed colour codes three decades after most other European countries, as the change in standard was not considered safe. Blue, previously used as a phase colour, is now the colour for neutral. Black, which was previously used for neutral, now indicates a phase. The new standard colour code does not use red.
This is because they have plastic casings, or they have been designed so that the live wire can not touch the casing. As a result, the casing cannot give an electric shock, even if the wires inside become loose. These appliances have double insulation and carry a symbol.
Step-by-step guide to wiring a plug
- Unscrew the plug cover. Loosen one flex clamp/cord grip screw, remove the other.
- Remove the fuse. Carefully lever it out with a screwdriver if necessary. Loosen terminal screws. Warning.
- Finally check: Wires are connected to the correct terminals. There are no stray 'whiskers' of wire.
The earth wire creates a safe route for the current to flow through if the live wire touches the casing. You would get an electric shock if the live wire inside an appliance, such as a cooker, came loose and touched the metal casing. This breaks the fuse and disconnects the appliance.
The plug. In a plug, the blue neutral wire goes to the left, the brown live wire to the right and the green and yellow striped earth wire is on top. The fuse fits next to the live wire. The diagram shows the key features of a three-pin mains plug.
The N & L stand for Neutral and Load. With your AC line in you should have three wires. Neutral, Load, and Ground. If your wires are color coded for the US then the black wire is Load or Hot, the white wire is Neutral, and the green wire is Ground.
What are the Old Wiring Colours? If any socket or junction box in your home has a red wire for live current, a black wire for neutral and green and yellow wires for earth, you should consider having them replaced by a professional electrician.
Hot: The black wire is the hot wire, which provides a 120 VAC current source. Neutral: The white wire is called the neutral wire. It provides the return path for the current provided by the hot wire. The neutral wire is connected to an earth ground.
A standard 2-wire lighting circuit is shown in Figure 1. The brown wire is Live (also know as permanent live), this brings the live supply to the switch. The blue wire is known as the Switched Live and takes power to the light. Switched Live is only live when the switch is on (this is where it gets its name from).
The faceplate of a single, one-way switch has two terminals: "L1" is the terminal to which the neutral core wire is attached - the blue wire (traditionally black, before the change). "COM" or "Common" is the terminal to which the live core wire is attached - this is the brown wire (formerly red).
A switch in the electrical circuit is always connected to the live wire so that the socket/appliance is not live when it is switched off. A fuse is usually a thin piece of wire that will melt and break the circuit if too large a current flows through it.
Fuses must be fitted onto the live wire so that when it blows, it will disconnect (isolate) the appliance from the high voltage live wire. (If the fuse is placed in the neutral wire, the electrical appliance is still connected to the high voltage live wire even when the switch is opened.)
Every three pin plug has a fuse connected to the live wire. The fuse has a thin piece of wire inside it, which is the weakest link in a circuit. If too much current flows, the fuse wire overheats and melts, breaking the circuit.
The Live wire always carries 230V with respect to the Neutral, which happens to be connected to Earth. If you connect the switch to the Neutral. The Live conductor will still be in contact with the device. The device will not operate because the current has no return path to Neutral.
A fuse is nothing more than a short length of wire designed to melt and separate in the event of excessive current. Fuses are always connected in series with the component(s) to be protected from overcurrent, so that when the fuse blows (opens) it will open the entire circuit and stop current through the component(s).
The remaining circuit breakers are connected in parallel to each other to various distribution points/rooms. If connected in series, it will be impossible to isolate a section/part of circuit. However, each circuit breaker is to be connected in series in the part circuit it is to protect.
The difference between short circuiting and overloading is short circuiting means phase wire and neutral wire are short each other unexpectedly.If short circuit is occurred then there is sparks and leads to fire. Overloading means increase the current value over rated value.
Any circuit's black wire should be considered hot or live. Black wire is never used for a ground or neutral wire and should be used as the power feed for a switch or an outlet. A black wire is often used in a circuit as a switch leg, the connection that runs from the switch to the electrical load.