It really is only a matter of personal preference.
Charles is probably the most expensive.

Xantrex makes some nice stuff and you can also include interver in the same unit.

I have a Guest which runs 24/7 12 months a year (except when underway) and has completed its 6th year so no complaints.

Main thing to consider if you are using batteries other than flooded check to insure your charger has settings to cover AGM and Gel, they carge at differenct rates and are actually chared in stages.

dave

Check out :charger-guy sales on e bay.. I bought a reman Pro Mariner galvanic isolator for $70.00 from him this past August... It was new as far as I could tell, he says that most of the stuff is returns that just can't be sold as new anymore. I am buying a 3 bank charger from him soon... From whats been posted on this site there are certain "smart" chargers that know how much charge to deliver to each battery depending on it's individual needs..

Sean

Here's an example of what this guy sells.. Only a dual bank, but check out his other stuff..
Sean

http://cgi.ebay.com/ebay...amp;hash=item255b21d0e1

Here's a 3 bank..I'll probably get one like this from him.
http://cgi.ebay.com/ebay...&hash=item2309919d75

If you spend a lot of time at the dock with the vhf radio, stereo, cabin lights and other 12 volt items on, you have to consider a charger with more amps.

Our 10 amp charger kept all 3 banks charged when we were away but couldn't keep up with all of our house power requirements when we were aboard. The stereo alone draws almost 10 amps. Each 12v cabin light draws over 2 amps (which is why many have switched to LED lights). So if we listened to the stereo and had just one 12v light on we were draining the house battery.

I installed a Xantrex inverter/charger. The 2500 watt and 3000 watt units have 3 bank capacity. It puts out 140 amps for the house batteries and 15 amps for each starting battery. The charging is 3 stage so they charge quicker and don't overcharge. It also has an equilize function which you use every month or two to recondition the lead plates and electrolyte.

..."The power is taken from the positive of one battery, and from the negative of the other. This way, each battery sees the same voltage in use."


I believe Doug is suggesting wiring paralleled batteries as follows:

Yes Peter, that is just what I meant. Your picture is so much better than my description.

This is most important at high currents such as starting where small differences in wire length will cause one battery to be lazy. Jeff, your diagram looks fine, as long as the wire lengths are similar. If you are using them as house batteries, it probably doesn't matter too much.

Over the years I have had the best performance with 2 six volt golf cart batteries in series.

My setup is simple.

Stb. (which is start and house battery bank) 2 six in series.
Port. 2 12 volt batteries. 1 battery is Port start and the 2nd battery is connected via a ACR (automatic charging relay)

The 2nd port battery stand ready and isolated from the circuit but if needed I can flip a switch which straps it into the Port circuit. One not in line it will automaticly open for charging if the voltage drops below a preset range. That way the battery is always charged and if I pull all the other batteries down.. I still have one start battery in reserve.

I also have the parralel switch to strp the port and stb batteries for starting which I usually do if I have been on batteries on the hook over night etc.


safe boating,

dave

Jeff,

Check out this link it explains the concept far better than I can. I can attest that it does work and works well. I know I always have a full battery in reserve.

http://continuouswave.co...Forum6/HTML/001232.html


http://bluesea.com/products/9112

The 9119 has been discontinued which is the model I have installed. The ML series has replaced it but performs the same. The main difference has the shielded terminals.



dave

That is a great find for an ACR. alternators installed.

Take not Jeff.. LOL


dave