Hi,
90 days in campgrounds over the last 1900 days of full time.
What MAY have shortened the Marine batteries life was a lousy solar controller that does not have temperature compensation, nor adjustable voltage set points.
I'd point out to you that solar is NOT a constant float. There is no charging going on when the sun is down.
My previous bank was 875 amp-hours of Marine jars. The were solar floated from day one and lasted for 9 years. I was able to equalize them via solar using bank switching.
My current bank is used AGM telecom jars that have been in service for 5 years. They, too, have been solar floated since the day I got them. I push them HARD (up to 225 amps draw).
For AGM to last one needs to be able to charge them at 0.2 C (20 amps for each 100 amp-hours of capacity). If this is not done, they will sulfate. It is MUCH harder to recover an AGM from such abuse and requires the end user to "dance on the needles".
A disconnect switch between the panels and the controller is a good plan, but it has almost nothing to do with charging. It is to protect the controller from letting out the magic blue smoke.
wopachop wrote:
It seems like most people on this site go to campgrounds. So their trailer is either stored or hooked to shore power. If you have solar without a disconnect that means your batteries are always fully charged and every morning get cooked at 14.4v. I still think that is what killed my deep cycle marine batteries premature. I read the trojan link many times over the last few years. It does not recommend a constant float on both sealed and flooded.