Date:         Mon, 12 Sep 2011 22:25:08 -0600
Reply-To:     Steve Williams <steve@WILLIAMSITCONSULTING.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Steve Williams <steve@WILLIAMSITCONSULTING.COM>
Subject:      Re: Charging circuit wiring upgrade/maintenance report/questions
              (longish)
Comments: To: Rocket J Squirrel <camping.elliott@gmail.com>
In-Reply-To:  <4E6E9244.1040400@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Hi,

Thanks for the info.  Now that I think about it a bit, I understand
better that the "loss" is going to be in the high current draw
situations.  Initially, I figured resistance is resistance...

What do you use for a 12VDC>12VDC charger?  I assume it's a smart
charger that is aware of the various (3?) stages of charging?  It's
funny you mention that because I was thinking of an inverter->12VDC
"smart charger" would be way better than just pumping the alternator
current at the battery.  I never even thought of a 12VDC -> 12VDC charger.

PLEASE no-one get into the charging logistics.  ;-)  There's lots of
articles in the archives and I have copied many of them to read up on as
my "next step".

Thanks,
Steve W.

On 9/12/2011 5:14 PM, Rocket J Squirrel wrote:
> Without knowing how much current is flowing from the alternator to the
> batteries, it's impossible to know what the copper and other resistive
> losses are. If the batteries are fully charged and there are no loads
> (headlights off, etc.) then one should see a negligible voltage drop
> even with skinny wire.
>
> But I'm no expert on these things, not seeing a reason to rework my
> wiring to obtain slightly faster charging of my engine battery. With
> my driving habits, it charges fine, as is.
>
> The 12VDC > 12VDC charger for my cabin battery limits current to 7.5
> amperes, fast enough for my needs. Besides, my Trojan 130 Ah deep
> cycle battery was a spendy little item and I like to baby it, perhaps
> overmuch, by charging it like I discharge it: slowly.
>