Popular Woodworking 2003-11 № 137, страница 79

The TRUTH

about 240V

Frankly, we're tired of the debate. So, we're ending it here.

Cabinet vs. contractor, metric vs. English, hand tool vs. power tool (yawn). When you're in the mood for a real debate, just bring up 120 volts vs. 240 volts among a group of woodworkers. Tempers will flare, arguments will ensue, indignation will linger.

We're passionate about our voltage and rightly so - it's the lifeblood of our motors. Its importance necessitates you know the facts. So here you go: You won't save a dime and your motors won't be more powerful if you switch to 240V. But, if you're running multiple motors at the same time or you're using the pre-existing wiring in your house, switching to 240V will eliminate voltage drops and stalling, as well as lengthen the life of many of your motors. In almost all cases, 240V is the better deal.

Before you pick up the phone, ready to give us an earful, read what we have to say. We've done our homework - the information here is backed up by facts, experts and experience.

Electricity 101

Before we dig into the debate, you must first learn how electricity reaches your home. Check out the glossary at right to make sure you understand these terms before we move on.

Now then, your utility company distributes electrical energy in your neighborhood through high-voltage conductors (what many people call wires) that terminate on step-down transformers. These transformers change the voltage to single-phase, three-wire, 120V/240V electricity, which is what you need in your home. From the transformer, three conductors (two hots and one neutral) supply your home with electrical energy.

In a residential electrical service, the two hot conductors are designated L1 and L2 and can be any color except white, gray or green. L1 and L2 each have 120V potential. The neutral conductor is intentionally connected to the ground and also can be referred to as the grounded conductor. Neutral

by Kara Gebhart & Greg Hyland

Greg Hyland is president of Cincinnati-based Cooper Electric. He has been in the electrical trade for 33 years and holds Electrical Contractor licenses in Ohio and Kentucky, as well as Master Electrician licenses in five local jurisdictions. Comments or questions? Contact Kara at 513-531-2690, ext. 1348 or kara.gebhart@fwpubs.com.

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Popular Woodworking November 2003