On Board Charger

[fish_hunt_guy]

Hey guys I got my first real boat this winter and just bought a 24v bow mount trolling motor. Now I will have 2 deep cycles up front and an all purpose deep cycle/cranking motor in the back for my gps/sonar graph and 90 horse outboard. Im thinking it would be nice to get an on board charger. What should I be looking for and can I and should I hook all 3 batteries up to it? I know the back battery wont be getting as low as the fronts but I would like to hook all 3 up just to always have fresh batteries if it wont mess with anything. Thanks for any advice!

[gunner55]

We have a MK 2 bank 10 amp/per bank that's hooked up to the alternator of our Yammie 115.It won't charge the TM batteries until the starting battery is charged.We have a 12v on the bow & a seldom used 24 for the transom.The boat sits on a lift that we have power to along with a smart charger that we can hook up.Unless I've ran the TM long & hard the batteries are all charged by the time I get back to the dock as it's a 1 1/2 miles out to the main lake.I know many here have the type of onboard charger the you plug in.MK,Dual Pro,& there's another that escapes me right now,I wouldn't go with anything less than 10-15 amps per bank.

[delcecchi]

I have had an onboard charger since I bought my boat. Especially with a 24 volt TM it is an essential piece of equipment as far as I am concerned. Either a 10 amp per bank, or 24 amps total, depending on the charger, will do a fine job of recharging everything while you sleep.

Do get a 3 bank and hook it to the cranking battery too. With graphs and live wells and stuff it can get run down.

[BoxMN]

And you can just extend the starting battery lead back to that battery no problem if you need to. Use the same gauge wire and quality rings. We solder ours at the splice but I'm sure many do not. I would just recommend putting the charger where it has some ventilation behind it and under it - the manual will come with install instructions. It will be the best thing you spent money on in a long time

Have fun with your boat!

[SkunkedAgain]

At least 10amps per bank is the way to go. Don't skimp. I bought a Cabela's brand 2 bank charger. It keeps my dual trolling motor batteries well charged. While I do run an Elite 7 graph off of my main motor battery, I've never had any issues keeping it charged, despite not having a 3 bank charger. The alternator on my 90 horse does the job, but I may not run my graph as long as others. I also typically fish big lakes so the motor gets ample opportunities to recharge the battery. When in doubt, go for the 3-bank. I'm more letting you know that you can get away with two banks.

Enjoy the new rig

[delcecchi]

For a long time I only used two banks on my charger. When I had the 115 Merc two stroke there were a few occasions that the cranking battery ran down.

A three bank charger isn't that much more money and will take care of all the batteries even when the boat has sat for a while.

[fish_hunt_guy]

Thanks for the replies. Is there adjustable on board chargers that you can adjust the amperage it gives out? Like a battery charger that you can set to charge at 2 amps, 10 amps, 30 amps etc?

[delcecchi]

Thanks for the replies. Is there adjustable on board chargers that you can adjust the amperage it gives out? Like a battery charger that you can set to charge at 2 amps, 10 amps, 30 amps etc?

Not that I know of, but I can't think of why you would want that. Chargers are so automated and intelligent these days that it shouldn't be an issue.

[delmuts]

I agree with del, in that you need to forget the thinking of a auto charger. The new on-board chargers are designed to provide the voltage you need and to maintain it safely.

[fish_hunt_guy]

Ok that makes sense. Last question and probably a dumb one but when it comes to chargers, does a model that is compatible with 24v systems, does one bank cover both batteries or do you need 1 bank per battery? Im assuming from what I've read you need one bank per battery but I wanna just make sure. Thanks again for the help!

[gunner55]

I forgot to mention that the Dual Pro are capable of being rebuilt.So,if you look around & want to save a few bucks that's an option.I have no experience with these personally but others here have with good results.

[Big Bobber]

I bought a rebuild about 3 hears ago and it has been working great.

[Kyhl]

One bank per battery and you want one that has the ability to distribute the charge to any of the banks.

For example, a 15 amp three bank should have the ability to supply 1 amp to each of two banks and the remaining 13 amps to one battery if needed.

[fish_hunt_guy]

Cool thanks Kyhl. Im looking at the MK330D I think thats what Im going to go with. This has the ability to distribute the amps around as needed right? and has the maintenance mode once all the batteries are fully charged so it wont cook the batteries right?.

[delcecchi]

The only other thing is how to set it for the various types of batteries, like Flooded, Gel, AGM, etc.

Pick one that works in a way that is convenient for you. (I only have flooded type old school batteries so don't have to worry)

[delmuts]

Fish. When you get one. Be certain to mount the plug so you can reach it from outside of the boat. Seems like common sense, but you would be surprised!

I've used Dual Pro for years,( had one rebuilt) and I'm very happy with them although a little on the pricy side. There are many good units out there. Sounds like you've found one that will work for you.

[leechlake]

delmuts, Amen to that. Mine is on the port side and the cord is kind of short in the storage compartment it's in. Would be a lot easier when it's on the trailer if the cord was long enough so I didn't have to hoist myself up and lay on gunwale to get at the thing both in plugging in and unplugging. If the boat is wet I get wet.

[BoxMN]

delmuts, Amen to that. Mine is on the port side and the cord is kind of short in the storage compartment it's in. Would be a lot easier when it's on the trailer if the cord was long enough so I didn't have to hoist myself up and lay on gunwale to get at the thing both in plugging in and unplugging. If the boat is wet I get wet.

You can mount a male "inset plug" not sure what it is called, in your boat in a location that is easy to get at from outside the boat. Then just plug in the cord, you don't even need to worry having a "cord" to the charger. We mounted this plug on the port side inside the gunwale. We have wider gunwale so it was pretty easy. Very foolproof now, easy to get at. Cost is cheap too, got it on amazoooon.

Another nice thing for folks who go to resorts or parks, get an nice heavy ext cord rated for the run, but also the thickness is good for if you have to park on the other side of a road when people drive over it. Last thing is get one with a lighted end. Friend had his plugged in all night one night, but found out in the morning that he had it plugged into a non-working outlet made for a slow day of fishing.... A lighted end would have let him know right away - our outlet was good and our end was lit, his was bad but he didn't know.

[marine_man]

You can mount a male "inset plug" not sure what it is called, in your boat in a location that is easy to get at from outside the boat. Then just plug in the cord, you don't even need to worry having a "cord" to the charger.

[PropsterII]

The only other thing is how to set it for the various types of batteries, like Flooded, Gel, AGM, etc.

Pick one that works in a way that is convenient for you. (I only have flooded type old school batteries so don't have to worry)

Does this matter? If you had an AGM for the starting battery and standard lead acids for the trolling batteries, your onboard should figure that out, there should be no adjustment you need to make, correct?

[delcecchi]

Does this matter? If you had an AGM for the starting battery and standard lead acids for the trolling batteries, your onboard should figure that out, there should be no adjustment you need to make, correct?

From listings online, it looks like some models need to be told and some figure it out.

[BoxMN]

The one we have I think has different settings for each bank.

[ClownColor]

The only other thing is how to set it for the various types of batteries, like Flooded, Gel, AGM, etc.

Pick one that works in a way that is convenient for you. (I only have flooded type old school batteries so don't have to worry)

Curious on this as well. I'm going to have two AGM and one lead acid...will the charger let me pick battery type per bank or just one setting for the charger?

[delcecchi]

I think most let you set it per bank, but to be safe check the specs on the unit you are thinking about. If it isn't clear in the specs, the manual can usually be downloaded to tell.

[fish_hunt_guy]

the new precision chargers you can pick which type of battery for each bank. The older ones I think are only designed for acid type batteries I believe. dont quote me on that though Id call minnkota