Things Electric
Several years ago, I was asked to conduct a seminar on basic electricity for the members of a small homeowners' association. They were working their way alphabetically through the various trade disciplines with which a homeowner might come in contact. As I recall, they had covered attic fans, brickwork, cabinetry, carpeting, decks and doors at previous meetings. I learned that I was to be followed in coming months by fences, fireplaces and
Why does the current flow? That was the question we left on the table at the end of our last session. We had pretty well nailed down the ampere as being the basic unit of measurement of electric current, in that it describes the quantity of flow of electrons from one place to another. We were about to examine the volt, the ohm and the watt when the current-flow question arose to command our attention. To get a firm handle on this, we are forced to backtrack a bit. Actually, we have to go back a long, long way - about 60 million years, to when a particular species of pine-like trees grew along the Baltic coast. Over the millennia, the resin from those trees became fossilized, producing the beautiful, beer-colored material called anbar by the
You don't have to be a football expert to sit in the stands on a nice fall day and watch the locals bash the visitors. But to get the most from the festivities, it helps to know the difference between a two-point conversion and an on-side kick. Being able to converse with your seatmates about the nickel defense and the single-wing offense surging back and forth before your eyes makes it even better. The jargon isn't just for the players and sportscasters. Electricity is a bit like that. Most of us are users, and most of us know some of the jargon despite the fact we don't work at a power plant. We know that we have 12-volt batteries in our cars and that the porch light takes a 60-watt light bulb. And for many folks, that's enough. I believe, however, that those of us who work with things electric on a larger scale can benefit from
The triennial publication of the National Electrical Code is an event of critical importance to any contractor or subcontractor performing electrical installations or repairs. First published in 1897 and produced since 1911 by the National Fire Protection Association, the NEC is now enforced in all 50 states and also serves as the basis for codes in several foreign nations. As has been the case with all editions published to date, the 1999 edition of the code is designed to ensure "the practical safeguarding of
