Funny fans
Q: Why is it that most large 3-speed electric fans go on in the following order: "OFF-High-Med-Low"? It would seem more intuitive that the first
setting after the "off" setting would be "low", not "high". Does it have something to do with the way the motor works?
A:
Your "the way the motor works" guess is on target: "It is harder to get the motor to start spinning at a slower speed than it is to get it spinning at a higher
speed," says Marcus Glass, of Lamp Depot. In some cases, the motor simply would not have enough power to overcome the rest inertia at the slow-speed
setting.
Three-speed fans typically mount the blades directly to the rotating shaft of the motor, says Christine Roehl, production manager at Casablanca Fans. You need
a "full jolt" to get them started up. Casablanca Ceiling Fans, on the other hand, start at a "low" instead of "high" setting because these fans have a flywheel
mounted to the rotating shaft. The motor gets the flywheel spinning first and the flywheel stores the excess start-up energy as kinetic energy. This allows the fan
blades to start at a slower speed.
There's also the customer to think about.
"Typically when an individual wants a fan on-they want to move air rapidly at first, then lower the setting to their desired level after a period of time," says Tony
Hodge, Vice President of heatersnfans.com.
When you turn the fan from "off" to the first on setting, it's on full-blast to cool you off fast. Then you can moderate the breeze by switching next to "medium"
or to "low".
(Answered by April Holladay, science correspondent, May 16, 2001)
Further Surfing:
Lamp Depot: direct sales
Heaters n Fans: direct sales
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