Chapter 9. Mastering Power

Lots of electronic stuff is powered from good old wall-socket AC voltage. That means lots of cords and connectors that can break or wear out or that have to be installed in new projects. This chapter shows you how to perform three common tasks for repair, maintenance, or new projects.

The goal of this first section is to teach you the rules of the road for AC wiring. It's not meant to frighten you but to give you the information to do the job safely and with confidence.

Note: This book does not cover household AC wiring, such as running cable for outlets and circuit breakers. If you have questions about performing this type of wiring, consult an electrician or other reliable electrical reference.


It's important to do AC wiring properly because AC power can supply a whole lot of energy. Faulty AC wiring — in the wall or in equipment — is a leading cause of fires. Do not cut corners on any wiring connected to the AC line! DO take your time and do the job right. It rarely takes much longer to use proper techniques, and whatever additional expense is incurred is cheap compared to the potential damage.


While you can use just about any old wire and components for the low-voltage DC part of electronics, the same is not true of wiring or components connected to the AC line. The insulation of wire used for AC wiring should be at least ...

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