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Chris Jones[_3_]

On 11/10/2016 00:26, wrote:
Sealed Lead-Acid batteries Do Not like to be run dead. Ideally, they
never should drop below 50% of capacity before being recharged.

Now, we get into hype and sales pitches. The "Advertised" range of
these little go-buggies is how far they will go downhill, with a
tailwind, carrying a 30 pound load after a full charge on a cool day.
The actual safe range is about 1/2 of that, 2/3 once in a great
while. Otherwise, the battery sulfates - and dies.

Fuses are not voltage-dependent devices, but current dependent. So,
as the battery starts to drop, and the regulator pulls more and more
current (at a lower voltage) to the motors, the motors will start to
overheat. And eventually the fuse(s) will blow to prevent damage to
the motors.

That could happen if the motor controller is very crude, but a good
motor controller would incorporate current limiting, and the current
limit should be set below the fuse blowing current.