Hair Dryers and Dim Lights, the Dummy Explanation

Brownout. not power surge

In what we suspect is one more attempt to defeat those pesky Google updates, the folks at Demand Media not only started separating our their eHow.com content into various niche sites (e.g., Techwalla.com), the company recently changed its name to Leaf Group. In honor of this change, this week we'll feature legacy DMS dreck ported from eHow to Leaf.tv, a site that (according to the DMS entry at wikipedia, is a company that produces "high-quality content for women"). We're starting simple, with newbie Andrew Hazleton and an article entitled "Why Do Hair Dryers Cause Power Surges?"¹

The correct answer, which Hazleton never provides, is simple: they don't. Hair dryers and many other appliances can briefly suck up enough amperage to cause a brownout on an electrical circuit, but in normal use, they cannot cause a surge. That's because a power surge is a temporary increase in line voltage, not a temporary dimming of the lights.

Andrew, though forced by the DMS formatting requirements to waste a couple hundred words explaining how a hair dryer works... "A hairdryer is made up of two major components. A fan generates a flow of air, and a heating element provides a source of heat..." ...eventually gets to the good stuff when he discusses the difference between startup power load and continuous load: "A hairdryer will be stamped with a wattage rating by its manufacturer. As an example, consider a 1500 watt hairdryer... for a brief period of time at start-up, the hairdryer may draw twice its rated current or more."

That "twice... or more" may be an overstatement, at least for a hair dryer, but we'll let it slide. It's what Hazleton says afterward that drew our  research staffer's interest:

"...there will be a momentary voltage drop on the circuit as the current surges. This can be seen in lights dimming or flickering."

Again, pretty much correct (and it ought to be, given Andrew's engineering degree). But there's still a problem: while writing a technically correct post, Hazleton forgot to educate his reader. As we said at the top, the OQ asked about "power surges," and he or she should have been told that the phenomenon is almost exactly the opposite of a power surge. Andrew failed that duty, big time, and that's why he's receiving the Dumbass of the Day award.

¹ The original has been deleted by Leaf Group, but can still be accessed using the Wayback machine at archive.org. Its URL was   https://www.leaf.tv/articles/why-do-hair-dryers-cause-power-surges/

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