A switch is an electrical device that controls the flow of current. At least one switch is used to turn on and off each electrical and electronic application device. Switches are classified into two types, one is an electrical switch, and the other is a mechanical switch.
One-way and two-way are these two electrical type switches. With the help of a 2 -way switch, we are also active in controlling the light fan we want to control, which operates from two places. In today’s article, we will see what a 2 -way switch is, why the wiring function of this switch is, etc. We will discuss this in detail today.
What is a 2-way Switch?
A 2-way switch is used to turn the same light or fan on and off from two different places. This switch is especially used in the area of the stairs or in a room that has two entry points. This type of switch is commonly used in some house wiring and in industrial applications.
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2-Way Switch Wiring
This switch consists of a total of three terminals, Common L 1 and L 2, respectively. The L1 terminals of both switches are connected in phase. And the L2 terminals of the switches are connected to one end of the bulb terminal, and the other end of the bulb terminal is connected to the neutral of the AC supply. The wiring diagram of the three-wire 2-way switch is as follows.
In the case of digital electronics, the configuration of three-wire two-way switch wiring is similar to that of the EX-OR gate.
| Sr.No | Switch 1 COM | Switch 2 COM | Light |
| 1 | L1 | L1 | OFF |
| 2 | L1 | L2 | ON |
| 3 | L2 | L1 | ON |
| 4 | L2 | L2 | OFF |
The light goes off when the common terminal of both switches is connected to the L1 or L2 terminals. The light is on when the COM terminal of the first switch is connected to the L1 terminal, and the COM terminal of the second switch is connected to the L2 terminal.
Similarly, the light is turned on when the COM terminal of the first switch is connected to the L2 terminal and the COM terminal of the second switch is connected to the L1 terminal. This is the function of a 2-way switch.
The front and rear of the two-way switch are shown in the picture below:
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Alternative Method of 2-Way Switch Wiring
The two-wire 2-way switch is mostly found in the industrial area and in some old houses. The COM terminal of the first switch is connected to the phase, and the COM terminal of the second switch is connected to one end of the lamp.
The other end of the bulb is connected to the neutral of the AC supply. The L1 and L2 terminals of both switches are connected together. The two-wire control two-way switch is shown in the figure below.
This configuration is similar to the EX-NOR gate of digital electronics.
| Sr.No | Switch 1 COM | Switch 2 COM | Light |
| 1 | L1 | L1 | ON |
| 2 | L1 | L2 | OFF |
| 3 | L2 | L1 | OFF |
| 4 | L2 | L2 | ON |
The light turns on when the COM terminal of both switches is connected to the L1 or L2 terminal. The light goes off when the first switch is connected to the COM terminal L1 terminal and the second switch is connected to the COM terminal L2 terminal.
Similarly, the light goes off when the first switch is connected to the COM terminal L2 terminal and the second switch is connected to the COM terminal L1 terminal.
In the schematic diagram above, the light mode is off, but the light is turned on when the switch is toggled.
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One Gang Two-Way Switch Wiring
When a bulb is controlled by two switches, a gang 2-way switch is used. Whose figure is as follows.
Figure A shows the mechanics of the 2-way switch, Figure B has the face of a single gang switch, and Figure C has a single gang two-way light switch. Connecting the common terminal and L1 terminal will turn on the light while connecting the common and L2 terminal will switch it off, which will also turn off the light.
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Multiway Switching
There are three types of circuits: open circuit, closed circuit, and short circuit. When the switch is in the off condition, it is known as an open circuit. The terminology related to the switch varies between the US and the UK. In the UK, they refer to 2-way switches and cross-over switches. While the US refers to a three-way switch and a 4-way switch.
US terminology is used in this definition. Let’s start with the basic idea of a light switch in an electric circuit. The basic circuits for turning lights on and off are shown in the figure below.
Suppose you have two entrances to enter a room. Now you will need different types of switches called three-way switches as it has three terminals. Between the two switches, both lines are called passengers. So you can turn the light on and off with the first switch and do the same with the second switch. Or you can turn on the first switch and turn off the second switch.
A 4-way switch controls a single light from more than two spaces. And it’s just across a switch or a cross-over switch that has two positions. This switch is installed between two switches and toggles the active passenger.
This means that in any switch, the lights are on or off; with this concept, you can add an infinite four-way switch to the circuit. Multi-switching is shown in the figure below.
Two-Way Switches
The prices of 2-ways witches manufactured by some companies are as follows:
| Sr.No | Two Way Switches | Brand Name | Current Capacity | Voltage | Cost |
| 1 | White Legrand Britzy | LEGRAND | 16 Amp | 230 V | Rs 146/Piece |
| 2 | Maddox white modular two-way switch | MADDOX | 16 Amp | 240 V | Rs 29/Piece |
| 3 | Schneider two-way modular switch | SCHNEIDER | 10Amp | 220 – 240 V | Rs 17/Piece |
| 4 | Affonso modular switch | AFFONSO | 10 Amp | 240 V | Rs 18/Piece |
| 5 | Arcitech 2-way electrical switch | ARCITECH | 6 Amp | 220 V | Rs 63/Piece |
Precautions for Safe Use
Some precautions for switches are outlined below:
- Do not do any kind of wiring while the power supply is on in the switch; otherwise, an electric shock may occur.
- Do not use switches in an atmosphere that contains combustible or explosive gases.
- Be sure to turn off the AC power supply before wiring, mounting, and dismounting the switch. Otherwise, the switch may burn out.
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Frequently Asked Questions
What are 1-way and 2-way switches?
The 1-way switch means you can operate a light or a fan from one place, and this is the most common type of switch we find in every home. A 2-way switch means you can operate the light from two places. Such switches are mostly used in the area of the stairs.
Two-Way Switch Connection:
Two-way light switching works by keeping two wires between two different switches. This is what both wires do. So this wire acts as an alternate bridge point between the two switches, which allows them to connect the circuit to the light source from either switch.
What is the difference between a 2-way switch and a 3-way switch?
A 2-way switch or a single pole double throw switch is a three-terminal switch. One of these terminals is the input power, and the other two terminals are the output. Because it uses two switches and one device. In a three-way switch, you use two controls on the same device from two different locations.
What are the advantages of a two-way switch?
The advantage of 2 way switch is that you can easily operate the same device from two places. This is used in the area of stairs and in large bedrooms.
How to execute alternative 2-way switch wiring?
| Sr.No | Switch 1 COM | Switch 2 COM | Status of Light |
| 1 | L1 | L1 | ON |
| 2 | L1 | L2 | OFF |
| 3 | L2 | L1 | OFF |
| 4 | L2 | L2 | ON |
How does a two-way switch work?
Both L1 terminals of the switch are connected to the live wire of the AC supply. Both L2 terminals of the switch are connected to one terminal of the light bulb. At the same time, the other terminal of the light bulb is connected to the neutral of the AC power supply.
What is the two-way switch?
If we say two-way switch easily, you can easily operate a single outlet from two places or by means of two switches; it is known as a two-way switch. Like the switch for the stairs, you can operate it from both the top and bottom positions.
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Thank you this explains how it works in simple terms.
I have a two-way switch for my bedroom light. How would you connect a Fan/Light fixture on this circuit?
Thank you for your help.
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