This past weekend, our neighbor had a problem with one of the circuit breakers in his house. While I’m no electrical wizard and certainly haven’t kept up with the electrical codes (that change more often than they did in the past.) I told him I’d take a look. The problem wasn’t all that complicated and we just changed the breaker.
But — this got me to thinking. Circuit breakers, like everything else have changed (and become more complicated) over the years. The first electrical distribution panel I ever remember looking at was in my parents house. It literally had two fuses — not circuit breakers — fuses. The entire house was essentially one circuit. If a fuse blew, electricity in the entire house went out. My grandparents lived in a somewhat more modern house… They had those two “main” fuses, but they also had couple of rows of fuses below those — there were actually separate circuits that were fused. So a fuse could blow and not necessarily interrupt electricity to the entire house. All these fuses screwed in like a light bulb — in fact, I’m not sure, but the base of light bulbs and the base of the fuses may have been the same size.
A number of years later, my parents bought a much newer house and the electrical distribution panel didn’t have fuses — it had circuit breakers! As I said, I’m not an electrician and these circuit breakers are pretty much what I remember for a lot of years… most probably until we moved here to West Virginia and moved into a new house.
The circuit breakers I remember until recently were either single-pole breakers or double-pole breakers. There probably were more differences, but here’s basically what’s different about the two:
Single-pole breakers — protect the “hot” wire of a circuit, supply a 120 volt circuit and usually protect circuits from 15 to 30 amps.
Double-pole breakers take up two slots in a breaker panel and protect two “hot” wires, they usually consist of two single-pole breakers with one handle and a shared trip mechanism, and can protect circuits from 15 to about 200 amps. These are usually used for large appliances like clothes dryers and water heaters.
When we moved to our current house, some of the circuits in the bathrooms and kitchen included outlets known as GFI (Ground Fault Interrupter) outlets — the circuit breakers for these circuits were single-pole breakers.
But looking in our breaker panels, I discovered a couple of circuit breakers I wasn’t familiar with — one was a GFI breaker, that I assumed did pretty much what the GFI outlets did, but there were other breakers called AFI (Arc Fault Interrupters.)
Doing a little checking, I discovered that the GFI does, in fact, do pretty much what the GFI outlets do — they cut power when they are tripped by an overload, a short circuit or a line-to-ground fault.
Arc Fault Interrupters (AFI) breakers were new to me — they’re designed to protect against an unintentional electrical discharge in electrical wiring that could cause a fire. These “arcs” are usually caused due to worn or damaged electrical cords… regular breakers don’t always trip in these instances because they are designed to respond to a sustained amount of heat — not a quick surge.
So — you probably didn’t expect to learn so much when you started this — but I thought it was interesting, and important, so I pass it along for what it’s worth. And besides, you don’t want to be like me and become road-kill on the technological highway…..
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