engsol wrote:
I'm re-doing the 30 year old electrics on my boat.

Good idea.

I've bought the AC and DC power panels, etc.
Now is the time to think about the battery charger.
I like the the specs of the Xantrex Truecharge 20 Plus, but...
the specs suggest a battery size of 2 ea 4Ds or a 8D.

Why? We have a 40, and a battery bank of 4 Grp 31s. It can fully charge
them during an overnight dockage/shore power avail.

My plan is to toss in a couple (100 AH start, 100 AH house)
of flooded cell Group 31s for now, and later go to AGM
200 AH batteries when the boat kitty is well again.
Will this scheme work ya think? Will the XTC-20 work?


Sure.

But why go to AGMs, unless you just like spending money? You can buy Grp
31s at a farm or truck supply for about 1/3 what a marine store sells
the same battery for, and they'll last many years if treated properly.
Unless you want to mount them on their side, or plan to have your boat
roll over, there's no reason to spend the extra money on AGMs IMHO. Some
people like them so as to brag about their batteries, though.

Wayne.B wrote:
Why not get an inverter charger?

I can tell you why we didn't. The huge charging capacity is mostly
wasted and the charging leg needs to be connected to an
isolator/combiner because the add-on "echo charger" is useless, the
units are bulky & more expensive than either component by itself, and if
it craps out (which they do far more often than the sellers like to
admit) you're out of both. Plus, if shore power goes down while you're
watching TV (or anything else using 120VAC) then you flatten your
batteries before you realize it.

OTOH if you're putting in one of those fancy computerized monitoring
systems, then it saves a heck of a lot of time on installing.

Fair Skies
Doug King