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Discussion Starter #1
Heya list!

This is something I've been pondering for a number of years. I think
I know the answer but I have doubts so I thought I'd put it out there
for consideration.

Does the increase of RPM associated with a runaway condition cease
immediately when current is removed?

In most of my brain it does. However, there this little doubting
section that says it should increase for a moment like some reaction
to inertial forces. I guess this comes from being used to ICE's that
have to burn that tiny bit of fuel that's left in the intake when the
throttle snaps closed?

So there it is. Any comments?

Trot, the wacky, fox...

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| /\_/\ TrotFox \ Always remember,
| ( o o ) AKA Landon Solomon \ "There is a
| >\_/< [email protected] \ third alternative."

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Discussion Starter #3
It will continue to spin, but it won't continue to accelerate.
Acceleration requires the addition of energy. The inertial forces just
keep it spinning, at gradually reducing speeds, until friction slows it
down and stops it.

> Heya list!
>
> This is something I've been pondering for a number of years. I think
> I know the answer but I have doubts so I thought I'd put it out there
> for consideration.
>
> Does the increase of RPM associated with a runaway condition cease
> immediately when current is removed?
>
> In most of my brain it does. However, there this little doubting
> section that says it should increase for a moment like some reaction
> to inertial forces. I guess this comes from being used to ICE's that
> have to burn that tiny bit of fuel that's left in the intake when the
> throttle snaps closed?
>
> So there it is. Any comments?
>
> Trot, the wacky, fox...
>
> --
> | /\_/\ TrotFox \ Always remember,
> | ( o o ) AKA Landon Solomon \ "There is a
> | >\_/< [email protected] \ third alternative."
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>


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Discussion Starter #4
yes and no
when the current is gone there is no more acceleration. however, you
don't actually turn off the current but the potential from the batteries
which motives current to run. you stop the current from being sustained
or increased but whatever current is running in the motor wires remains
until it is eaten in the motor as work (powering the motor) or
resistance in the wires. current has a 'small' life of its own. it's
much like inertia but in this context it probably doesn't give rise to a
noticable lag

Dan


TrotFox Greyfoot wrote:

>Heya list!
>
>This is something I've been pondering for a number of years. I think
>I know the answer but I have doubts so I thought I'd put it out there
>for consideration.
>
>Does the increase of RPM associated with a runaway condition cease
>immediately when current is removed?
>
>In most of my brain it does. However, there this little doubting
>section that says it should increase for a moment like some reaction
>to inertial forces. I guess this comes from being used to ICE's that
>have to burn that tiny bit of fuel that's left in the intake when the
>throttle snaps closed?
>
>So there it is. Any comments?
>
>Trot, the wacky, fox...
>
>
>

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For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 
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