Onboard Charger - Only Using 2 Banks of 3 Available?

[Jeff T]

I'm going to get a ProMariner ProSport 20. They have 2 versions of this charger - a 2 bank and 3 bank. The price difference is only $20.

Right now, I only have a 2 battery setup. I may add a 3rd this year, but I'm not sure when. If/when I get a 3rd, I will most likely run it in series with the deep cycle I already have. I'm not sure where the 3rd battery will go. It will either go across the transom or in the dry storage where my amps are. There certainly isn't room close to my current batteries.

My question is this. It is a problem to use the charger for a 3 bank setup only on 2 batteries? I'm guessing that I will have one set of charger cables free that I could just wrap with electrical tape and zip tie out of the way. My thought is go with the charger setup for 3 batteries and I might be able to use it on my 3rd battery with an extension...or I may never be able to hook the charger up to the 3rd battery. For the extra $20, it seems like it might be worth the money to have the option. Kind of like...better to have it and not need it than not have it and need it after the fact.

Thoughts? Just want to make sure it will work properly (and more important safely) if I'm not using all 3 of the charger's banks.

[chpthril]

I'm going to get a ProMariner ProSport 20. They have 2 versions of this charger - a 2 bank and 3 bank. The price difference is only $20.

Right now, I only have a 2 battery setup. I may add a 3rd this year, but I'm not sure when. If/when I get a 3rd, I will most likely run it in series with the deep cycle I already have. I'm not sure where the 3rd battery will go. It will either go across the transom or in the dry storage where my amps are. There certainly isn't room close to my current batteries.

My question is this. It is a problem to use the charger for a 3 bank setup only on 2 batteries? I'm guessing that I will have one set of charger cables free that I could just wrap with electrical tape and zip tie out of the way. My thought is go with the charger setup for 3 batteries and I might be able to use it on my 3rd battery with an extension...or I may never be able to hook the charger up to the 3rd battery. For the extra $20, it seems like it might be worth the money to have the option. Kind of like...better to have it and not need it than not have it and need it after the fact.

Thoughts? Just want to make sure it will work properly (and more important safely) if I'm not using all 3 of the charger's banks.

Ok, first, if you have one 12v starting and one deep-cycle right now, and plan to add a 3dr (2nd deep-cycle I assume) you will need to wire it parallel to the current deep-cycle. This way, you maintain a 12 system, as if they were wired in series, they would = 24V .

Now to your actual question. All you need is a 2-bank charger because the charger will see the 2 paralled batteries as one big battery. You can actually get by with a single bank charger and have it wired on the "House" bank, but if you want maintain the "starting" over the off-season, you will want the 2-bank. You can go with the 3-bank, but when you decide to add the 3rd battery (2nd deep-cycle) I would add in an ON/OFF switch between the 2 deep-cycles. This will allow you to separate them during charging and the charger will then actually see 3 batteries.

[Jeff T]

Thats what i meant. I mix those up all the time. I know what I meant in my head.