Carver Owners Forum

Now I am overwhelmed with the vast selection of 2-bank marine chargers on Amazon! How does one know which one to pick???

darylann wrote:Qr Bbpost Now I am overwhelmed with the vast selection of 2-bank marine chargers on Amazon! How does one know which one to pick???

Can you check your charger to see how many amps it is.....maybe there is a plate with the makers name and some specs.......it will tell you what you can replace it with without too much drama. Pronautic seem to be ok, for us anyway.

I just happen to have a picture on my phone of the plate on the old battery charger. Looking at it, I’m wondering why it says it’s a three bank charger, when there are only two batteries?

It just provides three isolated outputs, so that it could charge three separate banks. All the old chargers just had some diodes to isolate the battery banks, so you just had one unused port. The whole 35 Amps could have been used by one battery or shared by both (or all three if you had three).

That might be different with the new charger you buy. Many new chargers have dedicated outputs, say a 20 Amp two bank charger has two 10 Amp outputs. If you only use one then you really only can get 10 Amps (so if you have just one bank they recommend you connect BOTH charger outputs to that bank, so you get the full 20 Amps).

With a boat your size, I would go no smaller than a 30 amp, and I would probably recommend a 40 or even larger, but it depends on how much D.C stuff you will be running on board. You also need to verify the wire sizes if you go larger, but since your "charger" breakers on the panel were 40 Amps, then the wiring should support up to 40 Amps per battery (so, on some two-bank chargers that might bet two 40 Amp outputs, or an 80 Amp charger... that might be overkilll though)

I am so thankful for this forum and all the great information you all are providing! I love doing my own work on the boat whenever I can, and it’s all a never-ending learning process. I used to do my own work on my motorcycles as a teen, and now I am doing all I can on my boat, learning as I go. YouTube videos are awesome too. They helped me replace the joker valves in my heads in 2018, and change out the impellers in 2019, as well as the routine things like cleaning out raw water sea strainers, doing pump outs, learning about fresh water pumps, etc.

Pay attention to the existing wiring. The max charger size on a 15a circuit is 60a. Then there is the wire size Carver installed from the charger to the batteries to verify before installing something more powerful than the original. If you want to keep it plug and play then go by wiring size already there to dictate charger output selection.

That being said you can change wiring to go bigger if you feel it is necessary. In my case I am installing an 80a charger. This requires I replace the 15a breaker with a 20a, replace the wire from the breaker with 12gauge and increase the wire size from the charger to the battery.

A few things to consider especially if you're looking at off brands on Amazon;
- if it's being mounted in an engine compartment, ensure it's ignition proof
- look for a "marine"charger
- make sure it meets all North American safety standards
- judging by your current unit, ensure you get a 12 volt charger
- unless you want to replace your wiring, the charger's output to each bank can't exceed the limits of your current wiring/circuits. Don't just go by the breakers you currently have. While they are likely rated for the size of wire you have, the new charger may require a certain breaker rating above its rated output per bank, some require breakers 5 amps over their rated output while others require breakers 10 amps over their rated output to each bank, this is important for safety and to avoid nuisance tripping
- take note of the required input. It's likely your current circuit is 15A, 60 Hz (North America), 14/3 wire
- in general, the size of your battery banks, primarily your house bank, and the type of boating you do has an impact on the size (output) of charger you should get
- your charger's performance is only as good as the condition of your batteries, and your connections so ensure they are good quality coated connectors, and that they're clean and tight, use shrink connectors and shrink tubing

ProMariner ProNauticP series chargers are a good choice, I've installed many. If you're handy with tools, we can walk you through the installation.

Thanks so much for all the shared knowledge and advice!!!

Lots of knowledge here and people more than willing to share. Great group.