On the usa 120v plug, which side is +?

Answer 1

AC current is not + or - like a battery. But, if you want to know what is hot or neutral, and the cord with the side that is smooth is usually the hot side (but do not quote me on that).

Answer 2

In 120 AC current you don't really have a positive side; you're thinking of DC. According to the second link, when you obtain 240 via the two 120 volt leads, one is considered the positive, the other the negative.

The U.S. standard AC plug is "Polarized." That is, one prong is larger than the other. The smaller prong is the hot and the larger one the neutral. If you think of it in refrigeration terms it makes sense. A compressed gas goes out and an expanded gas returns, of course, that's an over-simplified version. All this assumes that the outlet in question is properly wired which isn't always the case.

There's still a lot of knob and tube wiring out there in older houses and people don't know what to do with it. Replacing it with modern wiring rarely occurs to them.

You have a hot, neutral and ground wire. In the U.S. the electrical cable runs as follows, the naked wire is the ground, the black is the hot wire and the white the neutral. Sometimes, they say, it's a red wire that's the hot wire and the neutral is the common. But most wire sold today in the U.S. in a three strand cable is black, white and naked.

Incidently, there's a lot of confusion with the 120/110 voltage. Supposedly, there's a lot of line drop voltage between the transformer and the house and that accounts for the confusion. It may leave the transformer at 120 but get to the house at 117 or lower.

In the U.S., two 120 lines are fed to the house. One with a neutral gives you 120 volts. The two with the neutral equals the 240.

Major appliances such as stoves, hot water heaters and clothes dryers usually run on 240. Older types had three prongs on the plug with the neutral running double-duty for the ground. Today's standards in the U.S. calls for four prongs for the additional one being a ground.

Answer 3

That is the plug used with AC (alternating current). In AC the plus switches from one pin to another 50 or 60 times per second so there is nothing you can think of as the + side.

The pin connected to the dark wire is the live voltage with the light colored one being a neutral and if there is a third pin it is the green wire of ground.

Answer 4

There is no + on an alternating current plug. The polarity alternates in a sinusoidal fashion between plus and minus with respect to the other terminal.

Jerry is wrong: the hot lead is black (or any other color than white in polyphase systems), the neutral is ALWAYS white, and the "safety ground" is green or green with a yellow stripe. If the neutral is installed with any other color than white, the wire ends MUST be painted white to identify the neutral.

On convenience outlets, the brass-colored terminal is connected to the hot, black, wire, the silvery-colored terminal is connected to the neutral, white, wire.

Answer 5

None. Because 120 Voltage is Alternating Current. The positive (+) or negative (-) are normally on DC like 12 V Battery.

Answer 6

If you look directly at a standard US plug. The bottom pin is the ground reference, the left hand blade (the larger one) is neutral and the right one is hot. As stated before, you can't necessarily view it as + or - since the amplitude is changing relative to the ground reference.

Answer 7

The larger prong on a polarized plug is nutral the smaller one is hot.

Answer 8

The White (silver) wire connection is considered positive.
The Black (brass) wire connection is neutral.
The Green (green) wire connection is earth ground
Yikes: wikipedia has the answer CORRECT

I transposed the Positive and Neutral in My answer SORRY

The White wire (Silver Connection) is considered neutral
The Black wire (Brass Connection) is considered positive
The Green wrie (Green Connection) is earth ground

Answer 9

Doh! It's the side oposite the "-" side! lol

Answer 10

plug it in and see.