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

With a switch loop yes, it should. The hot wire should come down from the ceiling on the white wire and go back up on the black wire. Just think ‘white down, black up’. If you wired it the other way around, hot black down and hot white up, you have a problem.

What is L1 and L2 on a light switch?

The L1 is the switched live going out to the light. A two way switch (for switching a light from two different locations like in a hallway) has a common (C) a L1 and an L2 terminal. L1 is off when L2 is on and vice versa depending on the switch position. You can use a two way switch for one way switching.

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 happens if I wire a light switch wrong?

If you damage the wires during installation, you could break the switch, or the wires could come loose. Loose wires present a danger when changing the light switch. Thirdly, you could create a short circuit in the switch. A short circuit can cause the breaker or fuse to pop.

What does Cu wire only mean?

Use Solid Copper or CU-Clad Wire Only The label tells you what types of wire the switch can be attached to. By default, most switches are intended for use on solid copper or copper-clad aluminum wire (CU is the chemical symbol for copper).

Does the black wire go to L1 or L2?

L1 (line 1) is a red wire and L2 (line 2) is a black wire. Together, they show the motor voltage. Having both an L1 and L2 indicate that the motor voltage may be 240 volts.

Is L1 live or neutral?

The faceplate of a single, one-way switch has two terminals: “L1” is the terminal to which the neutral core wire is attached – the blue wire (traditionally black, before the change). “COM” or “Common” is the terminal to which the live core wire is attached – this is the brown wire (formerly red).

Why does light switch have 3 black wires?

If the light turns on, the second black wire you connected to the switch is the switch feed and the unconnected black wire is the feed to the other loads. If the light doesn’t turn on, then it’s the other way around: the connected wire feeds the other loads and the disconnected wire is the light feed.

How do you wire an electric switch?

Hook the wire clockwise around the screw so when you tighten the screw with a screwdriver, the clockwise force of the tightening screw makes the loop wrap tighter around the screw. Gently push the new, wired switch back into the electrical box and screw it in place. Screw on the switch plate and turn on the power.

How do you wire two way switches?

The two-way switch will have corresponding wires or screws. Connect the white wire with the white wire, the black wire with the black wire and either splice the red wire with the black wire or attach it to the black wire’s source. The wires that were twisted together should be sealed with a locking wire cap.

What is a two way light switch?

Two Way Switches. A Two Way light switch is a simple single pole “changeover” switch with three terminals.

  • Standard two way switching circuit. A typical application is that of being able to switch the hall and landing lights on and off from both upstairs and downstairs.
  • Three Way (or more!) Switching.
  • Carter system.
  • Switching with multiple PIRs.
  • See Also