Join Date: Oct 2000
Location: Portland, OR
Thanked 30 Times in 29 Posts
Rep Power: 17
Re: New battery charger - Blue Seas P12, Sterling Power Ultra or....
I am not in the charger industry so others will have to comment, but one part of your post was interesting...
For about 20 years we have had an AGM ("spiralcell") emergency/starting battery because the best place for it is under an aft berth where there's no way to add water to a wet cell battery. I leave it off the shorepower charger due to the imbalance between capacity of the two banks. Our house bank is a pair of Trojan T-145 GC batteries (wet cell technology).
The charger is left on for the house bank all the time at the dock. I do switch in the stating battery on that charger for a partial day if we go over 3 or 4 months in the winter without running the boat. When underway I use the stock Moto 55 amp alternator to charge both banks for an hour, maybe once a month. That AGM always seems to stay fully charged when checked on, and I use it to start the diesel once in a while -- just did that a week ago matter of fact.
There are probably several "right" answers to your question, but this works for me.
As for chargers, I am now using a ProMariner, and the first one failed soon after the install due to a manufacturing glitch that caused the fan to seize up and overheat the charger. Warranty replacement resulted.
Used to have a Truecharge 20, but will not go back to Xantrex due to their poor customer service.
If this one dies, I might go with Mastervolt, as a local marine electronics shop seems to be having very good luck with them.