Date:         Wed, 1 Aug 2007 11:28:45 -0700
Reply-To:     "Mike \"Rocket J Squirrel\" Elliott" <camping.elliott@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         "Mike \"Rocket J Squirrel\" Elliott" <camping.elliott@GMAIL.COM>
Subject:      Re: Solar panel
Comments: To: Warren Chapman <vwsyncroguy@YAHOO.COM>
In-Reply-To:  <vanagon%2007080113583406@GERRY.VANAGON.COM>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Under the bench seat in a battery box is where our Group 27 lives. It
does chew up storage space, no doubt about it. Required cleverness to
shift other things to new homes.

If you can count on being able to recharge your battery every day then
50% usage ain't that bad with a good battery. The engineer at Blue Sky
Energy (solar controllers) told me that curves can be found on the
Trojan which show how long a battery will last under different discharge
conditions. He said (I can't find the curves he referred to on the site
to confirm) that you can get more amp/hours out of a battery with 50%
discharge than with 20% discharge. Dennis? Know what he was talking about?

--

Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
KG6RCR

On 8/1/2007 10:48 AM Warren Chapman wrote:

> Still trying to understand this battery technology regarding amp hour
> ratings. Don't quite yet understand the 5hr vs 20hr ratings.
>
> The Odyssey PC1200 (from the manufacuterers performance chart) shows a
> rating of 44AH at 20hrs.....I think an Optima Yellow is about 55 AH.
>
>  Why choose the Odyssey? Cheaper to buy?
>
> Without solar supplemental charging...a Norcold or Isotherm fridge using
> 2.7amps per cycle would consume 20-24AH per day and would draw down one of
> these by over 50% in a day.....not so good.
>
> I'd be more comfortable with 100AH in reserve. Guess the only place to put
> a 100AH sized battery would be under the rear seat and lose a lot of
> storage space.
>
> Warren C.
>