Lakeview Electric has over 30 years of experience in the Northern Nevada area, which means we’ve worked with a lot of different clients, as well as many of the same clients again and again. During this time we’ve been asked many questions, especially about residential electrical systems, including wanting to know the difference between a two and a three-prong outlet.
We’re happy to dive deep into the difference between these two types of plugs, so you can know and understand the risks and the safety features.
INSIDE THE HOLES
The holes of an outlet are a good place to start this discussion. On a standard 120-volt outlet in North America, there are two vertical slots. Newer or updated electrical outlets also have a small round hole centered below the two vertical slots. The hole is termed “ground”. The left slot, which is a bit longer than the other is called “neutral”, while the right slot is referred to as “hot”.
Electricity needs to flow through a circuit. The holes in an outlet create most of the circuit. Power flows from the small slot on the right to the longer slot on the left, or “from hot to neutral”. When you plug an appliance in, it completes the circuit, allowing electricity to flow through the appliance.
As for the ground hole at the bottom, it’s actually identical to the neutral slot… before we discuss the ground hole any further though, it helps to understand where the breaker box fits into all this
INSIDE THE BREAKER BOX
If you were to grab a thick strand of wire and stick it in both vertical slots at the same time (essentially completing the circuit, without an appliance) the wire would send a huge amount of electricity back to the breaker box. Under normal circumstances, the appliance, be it a microwave, curling iron, or light; would help absorb that power. In this scenario, though, the electricity would flow back to the breaker box, and just before getting there, the circuit breaker for that particular outlet would detect the surge and immediately cut off the flow of electricity. Without the circuit breaker, the outlet would overheat and it’s likely a fire would start in the walls along the wire.
By the way, we don’t recommend you actually stick a strand of wire in an outlet, this example was to show you the great care that goes into our electrical wiring, protecting us from such worst-case scenarios.
THE GROUND HOLE
We mentioned earlier that the ground hole and the left (neutral slot) are the same; this might seem confusing and pointless. However, if you were to go back to that breaker box, you’ll see that the neutral wire and the ground wire connection to the same place. So why do we need it? You know… other than “because all your appliances have three prongs).
Well, actually, it is because all your appliances have three prongs, or most of them anyway. Manufacturers started encasing powerful electrical connections in a metal box. It may not look like the power cord for the device goes into metal, in fact, many have plastic over the top of the metal. Regardless, the third grounding prong was added to protect people using these powerful appliances.
If a wire came loose inside the appliances, around the ungrounded metal case, there’s a high risk the wire would touch the metal, sending out a potentially fatal shock. With a third prong, if a wire broke or frayed, it would simply flow through the ground, protecting you.
So the only difference between two and three-pronged plugs has nothing to do with the amount of electricity flowing through. It’s simply a safer – much safer product.
CAN I CUT THE GROUND PRONG TO TURN A 3 INTO A 2?
We certainly don’t advise it, but technically nothing should happen if you cut off the ground prong. You’re disabling an important safety feature, but as long as the wires inside the appliance are intact, then you shouldn’t miss it. The problem, of course, is not knowing the condition of the wiring inside the appliance. Even a brand new product risks having a wire come loose.
While electrical systems have become more complex in order to protect us, that shouldn’t be seen as an invite to find and fix problems on your own. It’s very easy to end up (accidentally) causing severe property damage, or even hurting yourself. Working with experienced electricians can streamline the process for you. If you’d like to switch some two-prong outlets in your home to 3-prong, let us know, we’re happy to help.