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Old 12-09-2008
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Originally Posted by sailingdog View Post
How many batteries did you have in your house bank? The problem may be the size of the charger you're using. The Freedom 25 is an 130 Amp charger, and unless you've got four or more 6V golf-cart sized batteries, the size of the charger may be the problem. BTW, if you're going to go with Trojan T105 type wet-cell batteries, you'll need at least six for the charger to be about the right size. A battery charger shouldn't be more than about 20% of the battery bank's capacity for wet cells. Six T-105 batteries will be 675 amp hours of battery capacity, 20% of that is 135 amps.
So based on this, 4 Trojans would be 450 amp hours so the charger should not exceed 90 amps? That's a worry.

I have only four T-105's in my house bank. I also have a Freedom 25 charger. I also have a 185 amp alt on my main engine which routinely pumps 140 amps into the house bank when it's a little soft. I can't say I've ever had an overcharge situation because of this. I monitor the whole lot via a Link 20. My batteries aren't gassing and I'm not losing a lot of water.

Most cars have a 65Ah battery driven by a 55 amp alternator. That's quite a bit more than 20%. Most are wet cells.

I always thought that the regulator decided what amperage was delivered to the batteries. Not the charger.

Am I wrong? Again?

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