How come there are 3 prongs for 3 pronged plugs. (As in, what are the 3 prongs used for)?

Question

And the same question with 4 prongs: 4 prongs for 4 pronged plugs, what are they used for??

I knew it was for grounding - -. Thanks guys for the "reminder" ~.^ :p

Answer 1

The 3 pronged plugs are commonly used these days in household AC outlets. The top 2 flat plugs are the 2 plugs for current (i.e. current goes in one & out the other). The bottom plug is a ground in case there is a short circuit in the device you are using. The current is then grounded through the 3rd plug instead of your body.

Answer 2

Yes. The small hole(the 3rd prong) is the ground, and the two slits are power. In the box (behind the plug) the green screw is the ground. Ground is always coded green, except in the box where the ground wire is bare copper, attached to green screws. This is the same for every electrical box in your house. HOWEVER, i think it is the fact that there is two much on that circuit, not the GFI itself. The circuit breaker down at the pannel box is also a GFI, and usually everything else on the circuit with the GFI (plug) will shut off when the GFI (plug) trips. Try finding out what is on that circuit, and unplugging some stuff from it, or if it works for a bit just dont turn anything else on. Hope i helped :)

Answer 3

One prong is the "hot" lead, the other is the return or common. The one that doesn't look like the others is a ground. The hot and common result from the fact that modern homes have three lines entering, wiring across the two hot ones will get you 220 volts (say, for an electric stove). Wiring across the hot and common gets you only half that or 110 volts. The ground is for safety. If there is a short in the appliance, the 110 volts will be diverted to the ground which will lessen the possibility of a bad or even fatal shock.

Answer 4

For three prong plugs there is one prong for positive power, one plug for the neutral, and one plug for your ground. For four prong plugs, they can be wired a lot of different ways. The two most common are two prongs for positive power (2 110V legs to achieve 220V), one prong for neutral and a one for ground, and also 3 prongs for positive voltage with one phase each, and a ground. This is most common with 480V machine hookups.

Answer 5

One is the hot wire running the voltage usually 120, the other is the neutral wire the balance the load, the third is put on some plugs to ground the appliance or whatever you are using to prevent electric shock incase of a break in the load. The forth plug usually for ranges and dryers is for appliances which requires more power. It would be two hot wires at 120 each, one neutral, and one ground

Answer 6

Outside my house is a transformer, whose output is 230V, with a center tap grounded, mostly for lightning protection. At the peak of the cycle, one hot wire is at +165V, the other is at -165V. (Note the 230V is RMS, not peak-to-peak, see reference). The center tap is also wired into the house as the neutral wire, so current drawn by 115V appliances is carried by the wire rather than through the ground, where it would corrode pipes and do other nasty things.

If my gadget needs 115V, I connect it to the neutral wire and either hot wire. That's enough for the gadget to work. But for safety reasons, any conducting part that I can touch is connected to a separate wire connected directly to an earth ground. That way, if a defect connects the hot wire to an exposed conductor, the current flows through the ground wire and trips a circuit breaker or a GFI (ground fault interrupter) rather than flowing through me.

If my gadget needs only 230V, it needs only the two hot wires, plus the ground wire for safety. If it needs both 230V and 115V (like a travel trailer), it needs the neutral wire, both hot wires, plus the ground wire. Add yet another conductor if my gadget needs three-phase power, like a large motor.

Answer 7

a prongs plug hello

Answer 8

3prongs - earth, live, neutral

4 prong - earth, live, neutral x 2

Answer 9

1 hot, 1 neutral, one ground.
2 hot's 2 neutral, one ground.