The wide prong on the plug links the threaded base of light bulbs to the neutral terminal (the wider slot) in the receptacle. If the wires are reversed, the hot side of the outlet (the side that can deliver a shock) is wired to the threaded socket.
Considering this, which wire goes on the gold screw?
The black (hot) and white (neutral) wires carry the current, and the copper wire is the ground. Note that the outlet's screw terminals are certain colors. The white wire goes on the silver screw. The bare copper or green wire goes on the green screw.
To prevent shocks from the metal parts of a light, lamp cords and two-wire extension cords are always polarized. This means the plug has a small blade for the hot wire and a wide blade for the neutral wire, and the wires feeding those blades should not be reversed when you put a new plug on.
The two-prong plug of unequal size and the three-prong plug are polarized. By having the two different sized prongs or a three prong design, the electrical device can only be inserted into the electrical outlet/receptacle one way.
A polarized plug will have one prong wider than the other, which is the neutral, and usually silver-colored prong. The hot prong will be narrower and usually gold colored. With a non-polarized plug, you can wire either wire to either prong.
The left slot is called "neutral," the right slot is called "hot" and the hole below them is called "ground." The prongs on a plug fit into these slots in the outlet.
A little hard to read, but the left side says "hot wire" and the right side says "white wire". We'll put the black wires on the hot side and the white wires on the left side. First connect the ground wire to the green screw at the bottom of the outlet.
Black, Red and Blue are used for hot wires and White is used as the neutral wire in a 120/208 V circuit. Brown, Orange and Yellow are used as hot wires and gray is used as the neutral wire in a 277/480 V. For grounding, regardless of the voltage, Green is used.
The protective ground is green or green with yellow stripe. The neutral is white, the hot (live or active) single phase wires are black , and red in the case of a second active. Three-phase lines are red, black, and blue.
One side of the receptacle has (2) brass screws and the other side has (2) silver screws. The hot side of the circuit (black wire) should be wired to the brass screws while the neutral side of the circuit (white wire) should be wired to the silver screws. You only need to connect to (1) screw on either side.
The high voltage (about 120 volts effective, 60 Hz AC) is supplied to the smaller prong of the standard polarized U.S. receptacle. It is commonly called the "hot wire". If an appliance is plugged into the receptacle, then electric current will flow through the appliance and then back to the wider prong, the neutral.
There's a hot wire (positive), a neutral wire, and ground. I ~assume~ that in an AC circuit, positive correlates to positive, neutral to negative, and ground to ground. Transformers will correlate the +/- when changing DC.
Step-by-step guide to wiring a plug
- Unscrew the plug cover. Loosen one flex clamp/cord grip screw, remove the other.
- Remove the fuse. Carefully lever it out with a screwdriver if necessary. Loosen terminal screws. Warning.
- Finally check: Wires are connected to the correct terminals. There are no stray 'whiskers' of wire.
When wiring a grounded power cord to an appliance: The SMOOTH (right) side is hot = connect to BLACK. The GROOVED (left) side is neutral = connect to WHITE.
Neutral: The white wire is called the neutral wire. Ground: The bare wire is called the ground wire. Like the neutral wire, the ground wire is also connected to an earth ground. However, the neutral and ground wires serve two distinct purposes. The neutral wire forms a part of the live circuit along with the hot wire.
Neutral colors include black, white, gray, and sometimes brown and beige. They are sometimes called “earth tones.” In Circus, Georges Seurat uses many different neutral colors. You can see a few glimpses of red, blue, and yellow in this painting.
Lamp power cords are usually single color paired wire (white, brown, etc). Look at the wire carefully. One side will have ribs on it and the other side will be smooth and will probably have markings on it. The smooth side is the hot and the ribbed side is the neutral.
The solid/dashed lines on wires like the ones pictured in your question are used to indicate polarity e.g. for the "wall wart" power supplies. Usually* the wire with the white stripe or the dashed lines carries the "positive" (+) end, while the other, unmarked wire carries the "negative" (-) end.
If the fixture's two non-ground wires are not black and white but one of them is smooth and the other has a "ribbed" texture, the ribbed is to connect to the white of the box and the smooth to the other.
Step 2: Wire Up the Extension Cord Plug. Remember that the hot wire (black) always goes under the brass colored screw, the neutral wire (white) always goes under the silver colored screw and the ground wire (green) always goes under the green colored screw.
CONNECT the new wires to the new outlet: white (neutral) wire to a silver-colored terminal screw; black (hot) wire to a gold-colored terminal screw; bare wire to the green grounding screw. Make sure the cable sheath remains secured inside the box.
The white wire is the neutral, and all other colors are hot. Electricians often use black, red or blue wires to deliver electricity to a circuit from the main panel. They may use other colors for switch wiring, such as yellow or tan. Orange wires frequently are used to interlink smoke detectors.