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Old 04-08-2011 | 06:54 AM
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CGRetired
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From: Galloway, NJ
Default RE: Safety Message Electric Models


ORIGINAL: carrellh

ORIGINAL: CGRetired
What I've suggested in the past was that motor checks be done with the prop removed.
One of the first guys to bring electric models to our field gave this advice. While many glow engines will stop if the prop strikes something solid, the electric motor tries to keep turning until the power is removed.
You are right. And the reason for that is the nature of electric motors vs glow fuel or gasoline powered engines. With glow, you need the compression stroke to continue operating. Stop that.. even with a finger, and the engine will stop. With electric, however, the motor is propelled by magnetic force, which does not stop as long as there is current flowing through the motor windings. So, they just keep turning. My right index finger has three scars. One on either side of the one with stitches showing that the prop hit my finger three times as it was rotating.

The problem is, many, if not most, beginners don't realize how potentially dangerous electric motors can be when there is a prop attached to the shaft. Glow or gas can be dangerous, however, usually, you have to start them up first. With electric, well, a mistake, such as the original poster.. and me for that matter, made, can be inadvertent, and costly.

CGr.