How to Control a Light Bulb using Single-Pole (1-Way or 2-Way) Switch?

Electrical Technology

How to Wire a Light Switch using Single Pole Switch (AKA One Way (IEC) or 2-Way (NEC)?

In today’s basic home electrical wiring installation tutorial, we will show how to wire a single-pole light switch to control a light point using a one-way or single-way switch. The terms “two-way” and “single-pole” are used interchangeably for the same type of switch in the US and Canada.

We will use the basic SPST (Single Pole Single Throw) switch in this tutorial to control the ON and OFF operations of a lamp, bulb or a lighting point from a single location.

We will use the basic SPST (Single Pole Single Throw) switch in this tutorial to control the ON and OFF operations of a lamp, bulb, or lighting point from a single location.

Good to Know: Single Pole, Single Throw (SPST) switch is known as Two-Way switch, toggle switch or Light switch having three terminals (two for lines and one for ground) in North America (US – NEC). While it is known as One-Way or Single-Way switch (having two terminals) in the Europe, UK and IEC following countries.

Before go in details, we have to show the basic construction and operating mechanism of single way switch which is shown in fig below:

Below is a simple step by step tutorial with schematic and wiring diagram which shows how to wire a light switch to control the bulb/lamp from single place with the help of one-way or single way switch?

Related Wiring Diagrams:

Controlling a Lamp using Single Way (or 2-Way) Switch

Requirements:

Single Way Switch (SPST = Single Pole Single Throw) x 1 No
Lamp (Light Bulb) x 1 No
Short pieces of cables x 3 No

Procedure:

This is just like a series circuit i.e. all the components are connected in series. Just connect the Neutral wire directly to the light bulb and then connect the light bulb to the switch through middle wire. And then connect the live wire to the switch as shown in fig below. Fig given below shows the basic connection of light switch and their position i.e. when the switch is OFF, the circuit acts like an open circuit and the bulb won’t glow. To switch on the bulb, switch S₁must be closed to complete the circuit and glow the light bulb.

In fig below, schematic and wiring diagrams of light switches are shown which shows how to wire a light switch?

Also note that home wire colors may vary according to different areas. In addition, always use and connect the earth wire (direct naked wire to switches, and electrical appliances from earth link in the distribution board to reduce the risk of electric shock and hazard) which is not shown in the figures above.

How To Wire Switches in Series?
How To Wire Switches in Parallel?

The following wiring diagrams shows how to wire a light bulb to a light switch according to NEC and IEC.

Click image to enlarge

Good to Know:

Switches and fuses must be connected through Line (Live, Phase or Hot) wire.
Switches connection in series is not a prefer way to wire home appliances. Parallel or series-parallel wiring method is more reliable.
Less wires and cables are required in this kind of wiring connection.

How To wire Lamps in Series?
How To Wire Lamps in Parallel?

Warning:

The brass screws should be connected to the Hot (line, live or phase) wire using the IEC & NEC Wire color codes. In case of SPDT and 4-Way (Intermediate switches), black colored screws are used for Hot or common terminals. In short, the color for common terminal is different than other terminals.
The silver screws should be connected to the Neutral wire (in case of switched outlet)
The green screw should be connected to the ground / earth wire (Green/Yellow or naked wire)
If there are no color coded screws on outlets, refer to the user manual or contact a licensed electrician.
Neutral Wire is not required in 240V outlets wiring (US) Also, Neutral is never connected to the switches.
Use the suitable voltage and ampere rating of switch with appropriate wire size and proper size MCB according to the load rating.

Precautions:

Switch off the main circuit breaker to make sure the power supply is OFF before wiring an existing or new outlet or switch with an electrical/junction box.
Contact the authorized and licensed electrician for switch installation if you are not sure about the wiring diagrams.
The author will not be liable for any losses, injuries, or damages from the display or use of this information or if you try any circuit in the wrong format. So please! Be careful because it’s all about electricity and electricity is too dangerous.

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