Excerpts from CHAPTER 6

Circuit Diagrams

BEFORE YOU CAN WIRE a building, you must learn how switches, receptacles, sockets and other devices are properly connected to each other with wire to make a complete electrical system called a circuit--the path along which current flows. There are instructions and several wiring diagrams in this chapter that cover three-way and four-way switches. Included here is an excerpt explaining the internal construction of three-way switches and how they work.

Three-way switches

Fig. 6-13The switch used for controlling a light from one point is known as a "single pole" switch. "Three way" switches allow you to control a light from two points (not three, despite the name). With three-way switches you can turn a hall light on or off from upstairs and downstairs, or a garage light from house and garage, or a yard light from house and barn. Such switches have three different terminals for wires. Their internal construction is similar to Fig. 6-13. In one position of the handle, terminal A is connected inside the switch to terminal C; in the other position, terminal A is connected to terminal B. Usually, the common terminal A is identified by being a darker color than the other terminals which are natural brass.

The rest of the chapter covers--
Grounded wires
Wiring diagrams for receptacle outlets
Three-way and four-way switches

Chapter 2.  Planning Your Electrical Installation
Chapter 13.  Modernizing Old Wiring
Chapter 19.  Troubleshooting and Repairs


Park Publishing, Inc.
Softcover, 5 1/2 x 8 1/2 inches, 256 pages, 228 illustrations
44th edition, July 15, 2014
ISBN 978-0979294556
Price $14.95

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