eli5 Earth, Neutral and Live


What are the function of the three wires in domestic electrical appliances? I’m hoping for a very basic explanation, assuming I don’t know anything about electrics.

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Live supplies the electricity.

Neutral returns the electrical path to ground and is a *grounded* conductor. It completes the circuit.

The earth or “grounding conductor” is another *grounded* conductor that normally doesn’t carry any significant current (except perhaps a small bit of leakage). It’s there for safety so that if there is a ground fault that the circuit breaker can trip (or fuse blown). The metal chassis of an appliance will be tied to earth for safety reasons.

The earth and neutral are tied together at the panel and nowhere else.

Live and neutral carry the normal operating current, earth/ground is for safety.

Neutral is tied to ground/earth at the main breaker panel.

Ground doesn’t normally carry any current, but when there’s a fault it provides a safe return path for the current. If you have a metal enclosure, it should be grounded, so that if a live wire touches it, it trips the breaker or blows a fuse instead of sitting there hot waiting for someone to touch it.

You can’t use neutral for this, because a single point of failure on the neutral line can make the rest of it hot due to electricity conducted through the load.

Some appliances, especially those with plastic cases, don’t need the ground wire, because they’re double insulated(a single failure won’t cause a shock hazard).

Power comes in the active and goes out the neutral.

The active has protection on it that causes it to stop the electricity if something goes wrong.

If the active burns off inside an appliance it doesn’t have the neutral to take electricity away anymore, it becomes dangerous and can cause the appliance to give you a shock.

The ground wire is connected to the casing of the appliance so that if the above happens, the electricity now has something to take it away and trigger the protection to stop the electricity.