I am assuming it is due to requiring more electricity but I’ve had broken 3 prongs work with just 2
In: Technology
When you plug in a three-pronged plug, that third prong is providing an alternate pathway for electricity in the event of a fault. If you cut the third prong off of a plug, you defeat the safety feature. Also, adapters were designed to use the cover screw to complete a ground circuit on some older plug designs.Aug 20, 2015
This was copied from master sparky
It’s due to how the house was wired when built. Pre 1969, homes weren’t required to be grounded the same way as they are nowadays.
In wiring, you have 3 wires: hot, neutral, and ground. Pre 1969 building code allowed for just hot and neutral, which is the 2 flat prongs. After 1969, building code called for better grounding with electricity, so a 3rd ground wire was added for safety. If you go into a house built pre 1969, more than likely, if you check the receptacles you may see that the outlets are 3 prong, but the 3rd prong is improperly grounded as the house is wired with the old 2 wire system.
This is a cause for concern as without proper grounding, it can lead to electronics burning out, breakers tripping after a power outage, and arcs across the outlet which can cause fires to name a few problems. Bad wiring as described is actually one of the top causes of house fires. I’m by no means an expert, so take what I say with a grain of salt.
Reddit won’t show me the other 4 comments for some reason, so I may be just repeating the same thing as others, but it has nothing to do with how much electricity an appliance uses. It has more to do with the grounding requirements of said appliance. If there are exposed metal chassis parts that *may* become energized in the event of a short circuit, they will be grounded, which utilizes the third prong. The device will function without this safety ground, but if something inside shorts to ground, well, you’re on your own.
The third prong is a grounding plug. Generally it’s only used for things that have a metal chassis to provide an extra layer of protection.
In most AC circuits, the neutral wire acts as the ground. But in some instances, an appliance could become damaged and internal live wiring may come into contact with the external metal case. This would cause you to get shocked if you touch it. The ground wire connects to the metal casing, creating a lower resistance path to ground than your body. That third prong usually attaches to the neutral bus bar in your circuit breaker panel, or some other metal grounded object like an outdoor water pipe. Devices made of non-conductive materials like plastic, wood, or glass, don’t require additional grounding, so they don’t really need a third prong.
There’s a few parts to this. Three prong grounded outlets are fairly new, before that we only had two prong ungrounded outlets.
The reason for this is safety. If there is a fault, having a separate ground path can protect you. For example, if a metal appliance like an oven or a washing machine has a fault where the ‘live’ wire touches the metal case, the whole surface would become live at 120v. Touching it can kill you, so we don’t want this to happen.
We have an independent ground wire because it’s a redundant return path for current. Ground and neutral are bonded together at the breaker panel. In the case of our washer, the current will flow from hot through the ground wire, and back to the panel, where the breaker senses the short circuit and cuts power. Safety.
Some appliances are “double insulated” and do not require a ground connection because they are inherently safe, and have no chance of exposing you to line voltage. These generally have plastic housing and any exposed metal just isn’t connected to any electrical circuit. These types of appliances can use an ungrounded two prong connector.
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