You’ve probably noticed that appliances tend to have either two-prong or three-prong plugs, and your house likely has outlets to match. Ever wonder what the difference really was between the two options, and how outlets work in general? This article will help you understand:
The holes in outlets have particular functions. The left slot is slightly larger than the right, and the left slot is called “neutral” while the right slot is called “hot”. The hole below and between both slots is called the “ground.”
You may know that electricity must flow in a circuit to flow at all. In a battery-powered circuit, for example, electricity flows from one terminals of the battery to another. In an outlet installed in the wall of your house, electricity flows from the hot slot to the neutral slot, but not without first performing the task that your appliance offers. For example, electricity might run out the hot slot and through a plug to the motor of your hair dryer, which it powers before heading back through a separate area of the plug and into the neutral slot.
Appliances keep electricity under control by allowing certain amounts of electricity to run through their cords at once. This amount is generally measured in watts, so for example a 60 watt lightbulb or 500 watt toaster only needs and allows whatever relevant amount of watts of electricity to run through them at once. If you were to just stick a thick strand of wire into the hot slot and then stick the other end into the neutral slot, electricity would basically pour through the wire, to the point that your home’s circuit breaker for the outlet would hopefully detect the strangely strong surge and cut off the flow of electricity. These kinds of safeguards are extremely important for preventing the outlet’s overheating and starting a fire.
Something you may not have known: the ground slot and the neutral slot of an outlet are actually identical. If you go to your breaker box and take a look at where the neutral and ground wires from all the outlets end up, they all connect to the same place i.e. the ground. Grounding is a common and important aspect of managing electricity as it protects people who are using metal-encased appliances from receiving electric shocks.
How does grounding protect them? Well let’s imagine a situation in which a metal-encased appliance is dropped and a wire comes loose in its insides. If that wire happens to be hot and touches the metal exterior, the entire appliance is now hot and anyone that touches it will receive a potentially fatal electric shock. If that appliance is grounded, the electricity from the hot wire flows to the ground and trips the breaker in the breaker box, making it so the appliance won’t work at all instead of being insidiously electrified.
So why do so many appliances have a three-prong outlet, meaning that they use both the neutral and the ground wire, which are basically the same thing? Just to enhance the safety of the appliance.