When it comes to residential and commercial buildings line wiring, there are usually three conductors in NMB cable of which two is covered in plastic insulation (one white and one black in the US), and the third one is bare copper.
These Conductors Are Assigned As Follows:
Hot: The hot wire is the black wire which provides a 120 VAC current source.
Neutral: The neutral wire is the white wire, and its purpose is providing the return path of the electrical current which is supplied by the hot wire. The neutral wire is attached to an earth ground.
Ground: The bare copper wire is referred to as the ground wire. Just like the neutral wire, the ground wire is fixed to an earth ground, but these two wires serve two diverse purposes.
Purpose Of These Conductors:
The neutral wire and the hot wire form a part of the live circuit, whereas the ground wire is joined to any metal parts that are found in appliances such as a coffee pot or a microwave oven. This forms part of a safety measure in case of the neutral or hot wires coming in contact with metal parts somehow.
By fixing the metal parts to earth ground, the shock hazard is eliminated in case of a short circuit.
These three wires in an NMB cable are joined with the three prongs of a typical electrical outlet. Neutral and hot are located on the two vertical prongs and the ground wire to the prong on the bottom of the outlet.
You can either plug a three-prong plug (for appliances that require a ground connection for safety) or a two-prong plug (for devices that don’t need grounding) into a standard three-prong outlet.
With line-wiring installations, fuses or switches must be placed on the hot wire as opposed to the neutral wire. This way, in case of an open switch or a blown fuse, the current running through the hot wire will be prohibited from going beyond the fuse or switch into the circuit, minimising the risk of an electrical shock should a wire comes loose. So, it is very important that, all the wiring should be installed by professional or certified electricians who will maintain your wiring in well manner and help you to keep your life safe.
Is It Safe To Touch The Neutral Wire?
The wire that is grounded is referred to as the neutral wire because it doesn’t pose a risk concerning plumbing or exposed metal parts. Generally, the hot wire is dangerous. The neutral wire is not playing a role in the operation of electrical equipment but is there for safety reasons. In case of the electrical current returning through the neutral wire (only from a connected load that is completing the current flow circuit), you touching the neutral wire with a 0V, can’t give you a shock as such.
But it’s not safe to touch the neutral wire as some voltage between neutral (at a high potential) and earth can give you a shock or it often happens that wiring was done inaccurately, and in such an event it is possible that “live” may be wired to neutral and visa versa.