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What does a1 mean on a light switch

Author

John Castro

Published Apr 15, 2026

Power in to the commons, A1 for one light, A2 for the other light.

What does L and L1 mean on a light switch?

A one way light switch has two terminals which is a common marked as COM or C. 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. … Manufacturers don’t make decorative one way switches.

What is B1 on a switch?

B1 – Single Break, Ultra Small Subminiature Basic Switches B1 series basic switches are ultra-subminiature in size with mechanical life expectancy over 1 million cycles.

What Colour wire goes in L1 and L2 on a light switch?

Red for L1, Yellow for L2 and Blue for common. Brown for L1, Black for L2 and Grey for common.

What are the 3 terminals on a light switch?

There are three screw terminals on the body of the switch, in addition to the green grounding screw. One screw, known as the common, is a darker color than the others. The other two screws, usually a lighter brass color, are known as the traveler terminals.

Does the black wire go to L1 or L2?

The incoming circuit wires that provide the power are referred to as the line wires. 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.

What does l and 1 mean in electrical wiring?

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).

How do you wire a 12 volt switch with 2 switches?

1) Connect 12V from the battery to the middle connection of the nearest switch. 2) Run two wires to the second switch, one wire from top to top of the two switches. The second wire from bottom to bottom of the two switches. 3) A wire from the middle connector of the second switch goes to the +ve terminal of the lamp.

What color is the L1 wire?

RegionGround (G)Line 1 (L1)USA (LV)*GreenBlackUSA (HV)*GreenBrownEurope & UKGreenBrownUK (Old)GreenRed

What Colour is L1 wire?

FunctionlabelColor, commonNeutralNwhiteLine, single phaseLblack or red (2nd hot)Line, 3-phaseL1blackLine, 3-phaseL2red

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What is A1 A2 in switch?

With switches A1 and A2 in toggle up positions outlet is powered. A1 or A2 WILL turn power off by toggling down. A1 and A2 will power on/off (like std. … New switch Page 2 A2 box contains A2 and a second 3 way switch, (B1) for another circuit. There are three 4-wire cables entering/exiting the box.

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

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. The green or bare copper (ground) wire, if the device has one, attaches to the green screw terminal on the switch or to the electrical box.

What is a double pole single throw light switch?

A double pole single throw switch controls two circuits (poles) and has 2 states an “on” (closed) state and an “off” (open) state. A double pole single throw has four terminals in total, two inputs and two outputs which are all controlled by the same switch.

How can I tell which wire is common on a 3 way switch?

The switch wiring for three-ways is normally Red, Black, and White. If the White is correctly used for neutral, the connected switching wires are Red and Black. The White (neutral) is often referred to as Common, but the colored wires are both used as Hot wires, alternately as the possible switch positions are made.

Which wire goes where on a 3 way switch?

Wiring for a 3-Way Switch The most important wire to get right is the one connected to each switch’s common screw terminal. This is the “hot” wire (usually colored black, but not always), and it brings the power from the source and delivers it to the first switch and then from the second switch to the light fixture.

What wire do you use for a 3 way switch?

You will need two different types of 14 AWG wire, to wire your three way switch. You will need 14/2 Romex, and 14/3 Romex. 14/2 wire has two power carrying conductors, a black, and a white, plus a bare ground wire.

Is L positive or negative?

There is no ‘positive’ or ‘negative‘ terminals in AC but Line or Phase (L) or (P) and Neutral (N). They do matter , and one of the reasons is “Human Safety”. Even though, operation of the electrical appliance will not be affected by reversing them.

What does L L1 and L2 mean on a light switch?

A one way switch has a common (C) and Line out (L1) terminal. … 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 does L1 and L2 mean?

L1 and L2 are “line 1” and “line 2,” and “COM” is “common.” Depending on the position of the switch, either L1 or L2 is connected to “common”—hence the name; it is the terminal that is “in common” between the two positions.

Can I use a 2 way switch for 1 way?

Yes, a two way switch can easily operate as a one way. A two way switch is, at least in all the cases I know of, identical to a one way switch, except that it has two sets of contacts and a common. Simply omit wiring the second contact, and, of course, omit the second switch.

What does L1 L2 and L3 mean on a light switch?

Again, some makes of switch may have alternative markings such as L1 L2 and L3. This type of switch is used where two switches control one light, such as at the top and bottom of a stairway. It can also be used as a one way switch, by using the COM and L1 terminals only.

What are the 3 wires on LED lights?

LED Lights with 3 wires will be a multi-function light. They can (most times) be used in whatever configuration is right for your application. For example, running and brake, running and blinker or brake and blinker. These LED’s will usually have a black, red and white wire.

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

One of the black wires is the “hot” from your circuit breaker panel and the other black wire goes to the light fixture (load). If you’re using a regular light switch, then it doesn’t matter which wire goes to which screw, since the switch is just opening and closing the circuit to make the light turn off or on.

What happens if you wire a light switch wrong?

If a light switch is wired up wrongly, a short circuit may takes place if you give phase and neutral to the switch terminals. Always connect neutral wire to the one terminal of the light and phase to the one terminal of the switch and off wire to the other terminal of the switch to the light other terminal.

How do I know which wire is ground?

To tell if your home has ground wire, check your outlets. If your outlets have three prongs, then your home has ground wire. If there are only two prongs, then ground wire may not be utilized.

Why are there 2 black wires on light switch?

You should see two black wires, each connecting to a different screw on the side of the switch. These are called terminal screws. You will also see two white (neutral) wires that connect to one another in the box. … These are ground wires.

What do you do with the white wire on a light switch?

The white or neutral wire bypasses the switch and goes straight to your lights. This wire is needed to complete the circuit. The ground wire (sometimes in a green jacket) should be connected to your switch and to your lights.

What are the 4 types of switches?

  • SPST (Single Pole Single throw)
  • SPDT (single pole double throw)
  • DPST (double pole, single throw)
  • DPDT (double pole double throw)

What is the difference between a single pole and double pole light switch?

The pole of a switch refers to the amount of separate circuits that switch can control. Single pole switches can control just one circuit and a double pole switch can control two circuits.

What is the difference between single pole double throw?

A single pole will switch one wire by opening, closing, or changing the connection in a single conductor, while a double pole switch will control (by closing and opening) two separate wires or circuits at the same time. A throw, like a pole, can be single or double.

How can you tell which wire is hot without a tester?

For example, get a light bulb and socket, and attach a couple of wires to it. Then touch one to neutral or ground and one to the wire-under-test. If the lamp lights, it is live. If the lamp doesn’t light, then test the lamp on a known live wire (like a wall socket) to make sure it actually lights.