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# What happens to a 4v rated motor when I juice it with 12v? Answered

What happens to a 4v rated motor when I juice it with 12v?

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<p>The operating voltage provided by the manufacturer tells you at what voltage the motor runs most efficiently. Ive noticed that running most motors at 30% or above there limits will shorten lifespan and your ability to use the motor. Drrr. <br /> This said...<br /> <br /> 4v=Recommended<br /> 12v=More FUN!<br /> <br /> Play around, small DC motors are in everything. See what you can get out of the little thing, maybe evan as a hampster cage heater if all its doing is making extra heat at a higher voltage.</p>

all of the above or below

Under it's RATED load capacity (that is, the work it is doing - like turning a propeller in a boat or whatever), the motor will generate enough heat to cause catastrophic failure; in other words; if it is used to propel a boat through the water at the higher voltage, you should eventually end up with: <br /> <br /> <object height="313" width="384"> <param name="movie" value="http://www.youtube.com/v/9jp3de50_d8&hl=en&fs=1" /> <param name="allowFullScreen" value="true" /> <param name="allowscriptaccess" value="always" /><embed allowfullscreen="true" allowscriptaccess="always" height="313" src="http://www.youtube.com/v/9jp3de50_d8&hl=en&fs=1" type="application/x-shockwave-flash" width="384" /></object> <div id="refHTML"> </div>

It'll run, fast, but not for long. It will overheat very rapidly.

Well, I've been running with that voltage for quite awhile and still no short. it isn't even getting warm. I read up on the web and discovered that the voltage limit for a motor is the temperature it can take before melt down. melt down occurs when the supplied voltage is around 20 times the recommended voltage. higher voltage will shorten the lifespan, but at only 3 times the recomended voltage I think It will be fine.

I once ran a teeny 1.5 volt at 12 volts and it only got hot, so i un-plugged it and let it cool down.

what do you all think? objections?

Your assumption is probably based on an unloaded motor, where the motor's back EMF is resisting the supply voltage. When the motor is loaded, the back EMF falls and the current increases - on a higher supply it'll increase very rapidly. I'd suggest this motor isn't very heavily loaded, if its surviving.

Correction: Meltdown is not _likely_ until 20 times the recommended voltage. This is a game of probabilities, as with many engineering ratings. They set the rating at a point where they believe the product will almost never fail. As you trespass beyond that point, the risk increases. If you run it hot and it fails, or sets something on fire, it's your own darn fault rather than the manufacturer's, even if you run it only slightly hot.

Bottom line: "Do you feel lucky? Well, do ya...?:

He is right! I've done it lots!
And it stinks like nasty burning things, too. Just so you know.

It will run 3x faster and burn out 2000x faster than it would at 4v.

It'll go stronger and faster, but you increase the risk of it failing and possibly setting things on fire, but at only 3x recommended voltage it shouldn't be too bad, just remember, if it gets too hot, turn it off.

Do you mean before, during or after it melts down?

Before: It may run for a few seconds, probably at speeds it wasn't designed to withstand. Or, it may just jump directly to the 'During' step.

During: The copper windings will overheat, the insulating coating will melt and the wiring will short out and probably melt the copper, sometimes flaming will result. There will definitely be some smoke.

After: The motor is ruined, most likely beyond any reasonable chance of repair. Toss it in the trash.