Churning with voltage and resembling an explosion at the wire factory, the breaker panel exudes mystique. But it's just a big switch, filled with other smaller ­switches, which lead to the switches ...

Q: Several weeks ago, I read your column about installing electrical wiring. I’m curious about circuit breakers. What is the primary purpose of circuit breakers? Are there different types of breakers?

A circuit breaker that trips repeatedly is often assumed to be defective, but that assumption is frequently wrong. Breakers respond to conditions downstream, and replacing one without understanding ...