QA

Question: When Wiring A Light Switch

Does it matter which wire goes where on a light switch?

Originally Answered: Does it matter which black wire goes where when changing a light switch? If it’s a single pole switch with two terminals, the answer is no. One wire is the power to the switch and the other wire goes to the light.

How do you wire up a light switch?

Does the hot wire go on the top or bottom of a single pole switch?

If you are speaking of a single pole switch, doesn’t matter. On a 2 pole switch, box mounted, technically it doesn’t matter, but good practices are line at the top, load at the bottom. If a disconnect switch, always line at the top, load at the bottom.

What color wire goes where on a light switch?

The white (neutral) wire connects to the silver screw, or you place it in the back wire hole on the same side of the device as the silver screw. The black (hot) wire goes to the brass screw or into the hole in the back of the device on the same side as the brass screw. This wire is sometimes red.

What happens if I wire a light switch wrong?

This makes things like lamps and many appliances more safe to operate. But here’s the catch: If you connect the circuit wires to the wrong terminals on an outlet, the outlet will still work but the polarity will be backward. The white (neutral) wire should be connected to the silver-colored terminal.

Why does light switch have 2 black wires?

You should see two black wires, each connecting to a different screw on the side of the switch. These are called terminal screws. These are ground wires.

What is the common wire on a switch?

The common is for the live wire that supplies the input voltage to the switch. The other terminal is marked as L1 and is the output to the light fixture.

Which wires go where in a light fitting?

If the light fitting you have purchased has just two cores – live (brown) and neutral (blue), connect the live to the switch live terminal and neutral to the neutral terminal. If the fitting has an earth core, it must be sleeved with a yellow and green coat and connected to the Earth terminal.

Which wire is the load wire on a light switch?

Load Wire – Generally connected to the top half of your switch. If the wire is coming from the top of the switch box, it is likely your load wire. Line Wire – Generally connected to the bottom half of your switch.

Which wire is hot on single pole switch?

A single-pole switch has two brass terminal screws on the side that receive the black (“hot”) wires of the circuit. One black wire comes from the power source and the other goes to the light(s).

Do single pole switches need grounding?

If you are replacing a switch a ground is not required, as per the above exception. However, if you’re installing a switch; replacement or otherwise, into a metal box that is grounded. The switch will be ground via the devices yoke and mounting screws. So if the metal box is grounded, the switch is also grounded.

Does a single pole switch need a neutral?

Question; A single pole switch does not need a neutral, so why would you want a neutral in the switch box? Answer; Because changes or additions might require a neutral. Since there is no neutral in the switch box you cannot; – Install a digital timer – Install a motion sensing switch.

What are the 3 wires on a light switch?

A 3-wire NM connects the traveler terminals of the first and second 3-way switch together. Traveler wires are interchangeable on each switch. The common terminal of the second 3-way switch connects to the light fixture(s). The white neutral wires are connected together in each switch box.

What color wires mean what?

Electrical wiring comes in one of several colors: Black Wires – when you see a black wire, always assume it’s live. Blue Wires – always assume they are live if you have power. Blue wires are also fed through a conduit, usually bringing power to three or four-way switches. Green Wires – green wires are grounding wires.

What are the red white and black wires on a light switch?

Going out of both boxes and into your light fixture will be 14/3 wire, which has a black wire (hot), a white wire (neutral), a red wire (traveler), and a bare copper wire (ground).

Can wiring a light switch wrong cause a fire?

Wiring a smart light switch wrong can result in the switch not working correctly. If the wiring creates a short circuit, it can lead to damage to the switch and/or a burnt-out fuse. Errors can also lead to electric shock, fire, and a violation of local wiring codes.

How do you know if a light switch is wired wrong?

If either wire at the light fixture is still hot then the switch is wired incorrectly. If one of the wires is still hot at the light fixture with the switch in the off position, then you most likely have the light switch on the neutral wire.

Why are there 2 red wires on light switch?

When a light is controlled from two locations, you need a switch called a 3-way. A basic 3-way switch has a black wire or connector, called a common, and two traveler wires, usually black, red or blue. The two travelers may be the same color or different colors, but the switch itself will usually be marked.