Rob,
That battery would probably be in the 100+ AH range. The CCA is Cold Cranking Amps, and is the maximum current the battery can deliver for 30 seconds at (I think) zero degrees F. I'm guessing that the 1150 MCA is Maximum Cranking Amps, measured at a much higher temperature.

Amp-Hours is the rating of the battery under a steady load, I think 20 amps is the standard. If it'll deliver 20 amps of current for 5 hours, that's 100 Amp Hours. The AH rating is much more useful for a trailer than the CCA rating. Also, a battery rated for deep cycle use will generally last a lot longer when it's discharged a ways, then recharged, and repeated. Automotive batteries are meant to deliver lots of current for a very short time, then be immediately recharged. They're sent to an early grave when they're deeply discharged, especially frequently.

Jim

ROBBDAHL@aol.com wrote:

> I noticed there is talk about 105 amp hours, what is the difference between
> that and the New Interstate Marine/RV battery that came with that 1989 23
> footer I bought at the auction. The Interstate Battery does not say amp hours
> rating, but has 975 CCA and 1150 MCA. What would the Amp hour rating on this
> large battery?

--

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jdunmyer@toltbbs.com
lower SE Michigan, USA