3 way switch

3-Way Switch

One of the most important devices inside a house is the Switch. It makes and breaks the connection in an electric circuit. In Layman’s term, it turns on and off an electrical device. Like the common light switch on our walls.

We all have this at home. When we enter a room this is the first thing we touch to have the lights on. What magic it is to tick that tiny thing on the wall, and….boom! Everything’s visible. How amazing is that?

The Work of a Switch

A Transformer is supplying electricity in each of our homes. The current will flow to our house with the use of wires. Imagine how many meters of wire the entire world used. From the transformer’s wires will go to the Meter. Meter is what will measure the consumption of electricity we are making. The wire from the meter will then run going to the Main Switch.

From the main switch, you can now have electricity to the Switch Board, which will let you turn on and off the light. That’s fast, right?

Now the easiest way to explain why we have light at home is like this: Transformer – meter – main switch – switchboard – light.

Transformers always have electricity. It doesn’t matter if the switch is on or off. When we press the “on” button, the current will flow and the light turns on the bulb. The opposite happens when we press “off. It will block or stop the electricity, the reason why we can’t see any light.

The Usual

Before going to some “complicated” setups of switches, let’s first know the basics. Inside our houses, we usually have the “one switch to one bulb” set up. This is a “single pole light switch”. This is the most simple type of switch. The best way to start learning how some electrical wonders work. Let’s learn the set up of this.

The materials we need are:

  • Light switch
  • Switch Box
  • 2 wire cable
  • 3 wire cable
  • Wire nuts
  • bulb
  • Ceiling box
  • And of course, we need an electrical tape

This has two Terminals and a Ground Connection. If we take a look inside the switch, we can see a Track that carries electricity. By flipping and toggling this track, we can control the flow of electricity. This means you can turn on and off the light bulb.

Please make sure to turn the power off from the main switch before you start.
  • First, run the black hot wire to the bottom terminal of the switch. After that, run another hot wire over to the ceiling box and into the light fitting.
  • The next step is to have a white neutral wire in and connect this into a wire nut inside the switch box.
  • You should run another white neutral wire from the wire nut into the ceiling box, and into the light fitting.
  • We always need to make our circuits safe. This is the use of a “Ground Wire”. Connect this into a wire nut inside the switch box.
  • Another ground wire from the ground terminal of the switch and connect this into the wire nut
  • Plus, another ground wire from the ceiling box and connect this into the ground wire nut.

When the switch is off, electricity from the main power can still reach the switch. But, it cannot pass beyond because the track inside the switch is open. When we press the switch to on – close the track inside, the current will flow through the lights. The circuit is now complete and the light bulb will glow.

We’re done with the simplest way of setting up a switch. We’ll now jump to a 3-way switch set up.

3- Way Switch Set-Up

I know what’s in your mind, “why is there a need for multiple switches?”. That’s a very good question though. Come to think of this. You are going down your basement and the way down there is dark. You put a light bulb somewhere in the middle of the way there. Now, where will you put your switch? Of course upstairs so before you go down, you can turn the lights on, right? But, what about if you need to stay in the basement and you want to turn the light on the stairway? This is the use of a 3-way switch.

A 3-way switch is different from a regular switch. It has 4 screw terminals.
  • Ground
  • Common Terminal
  • Two screws are Traveler Terminals

There are three ways to wire a 3-way switch, one is “Light After Switches”, second is the “Light Between Switches”, the third one is “Light Before Switches”.  Since my example is in a stairway, we will discuss the second set up. Light Between Switches.

Here’s what we need to make this possible:
  • 2 wire cable
  • 3 wire cable
  • Ceiling box
  • 5 pieces of wire connectors
  • 2 pieces 3-way switches
  • 2 pieces of switch boxes
  • Bulb
  • Light fitting
  • And an electrical tape
And here’s the process:
  • From the power supply, connect the black hot wire to the common terminal of switch #1
  • Run the black travel wire from the left travel terminal of switch #1, and take this over to the wire connector in the ceiling box
  • Run another black wire from the wire connector and connect this to the left travel terminal of switch #2
  • Run a red travel wire from the right travel terminal of switch #1, connect this to the wire connector inside the ceiling box
  • Run another red wire from the wire connector, connect it to the right travel terminal of switch #2
  • This time, we bring a neutral wire in from the incoming supply, connect it to a wire supply in switch box #1
  • Run another neutral wire from the wire connector through the same box, then connect it into the light fitting
  • Run the third white wire from the fitting terminal to the common terminal of switch #2
  • This is where we now use electrical tape. To mark both ends of the third white wire, which means “ hot”.
  • Safety is always our priority. We will now bring our ground wire into the wire connector, then we connect to the ground terminal of switch #1 into the wire connector. Run another ground wire from the wire connector to the wire connector within the ceiling box. To ground switch #2, run a ground wire from the ground terminal going to the ground wire connector within the ceiling box
There we go! We can now turn on and off our lights from different parts of our house! Again, if we are not confident enough to do this, we can always ask for an expert’s help. Let’s be safe.

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