Electrical Extension wire Box: In this post, you will learn to make an extension box, containing 3 switches and three plug sockets. The circuit layout is as shown below.
Wiring diagram of an extension wire box

Main requirements
Switch Board
A switchboard is a board made up of either wood or plastic (PVC) and is meant for mounting
switches and sockets.
Mounting of Switches and Sockets
The procedure of cutting of holes of appropriate size and fixing of switches and sockets on switch board is known as mounting of switches

Wiring of SwitchBoard
The procedure of making electrical connections to switches and sockets according to the wiring
diagram is known as wiring of switch board.

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Apparatus Required
- Switch board of appropriate size,
- Three single pole (SP) switches (250 V, 5 A),
- 3 three pin socket ( 250 V, 5 A),
- 1/ 18 SWG wire,
- Screw driver set
- Pliers
- Insulation stripper
- Test lamp, etc.
Steps to Make Electrical Extension Box
- Mark the positions of switches and socket on the switch board.
- Cut the holes on the switch board for housing switches and socket, as per marking.
- Fix the switches and socket on the switch board.
- Make the wiring of switch board as per wiring diagram.
- Also, connect proper earthing connection as per wiring diagram.
- Make sure that all the connections are as per wiring diagram and are tight.
- Test the switch board
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