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Old 03-03-2013
btrayfors btrayfors is offline
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Re: Charging time and charger output

As usual, MaineSail has it exactly right!

The information cited from the NOCO site is totally wrong.

Example:

- you have a flooded golf-cart battery bank totaling 450AH (4 T-105s in series/parallel).

- this bank is at 50% state-of-charge

- your 120 amp alternator with external smart regulator is putting out 112 amps @ 14.8 volts (about 25% of the AH capacity of the house battery bank)

- you wave your magic wand and switch to an alternator having a 1,000 amp capacity

- this huge alternator is now putting out 112 amps @ 14.8 volts....same as the smaller one

Why?

Because, as Maine said and anyone who's experimented a bit with charging voltages and currents can tell you, the batteries will only accept so much charging current at a given voltage and state-of-charge.

It doesn't matter a whit how large your charging capacity is....the batteries will themselves limit the charging current.

It takes hours...sometimes many hours....to reach a full charge.

And, in this example, they won't reach full charge a minute faster with a 1,000 amp alternator than they will with a 120 amp alternator, given the same charging voltages.

Bill
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