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Re: (ET) 12 v marine batteries
On 30 Jan 2019 at 18:44, Chris Zach wrote:
> remember, twice the voltage means half the amps
I'm not an EE, just a hobbyist, but that's not what I learned. Ohm's law
says that I = E/R, so for a given load, current is directly proportional
to
voltage.
The situation is more complicated when the motor is running at normal load
and speed (back EMF and all that), but my concern would be with what
happens
when you get to the end of travel, or have a very heavy load that keeps
RPM
way down. Under stall or near-stall conditions, double the voltage means
about double the current.
It's the current that makes the heat that burns out your armature. That's
part of what the fuse is supposed to protect against. But since it's
still
current that concerns you, not power, I don't see the need to halve the
fuse's rating. I'd think that would just cause nuisance opens. What am I
missing here?
David Roden - Akron, Ohio, USA
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