BATTERY CHARGER QUESTION HELP

[Phil]

If I have 3 batteries on board for 24 Volt system , for an on board charger, is all I need a 2 bank charger or do I have to have a 3 bank ? Also on a older engine, do I have to disconnect battery before charging to keep from blowing rectifier in engine ?

Jigs

[Romeo D]

I have a 36volt system and 4 batteries on a 96 ranger. I bought a 4 bank charger because I run all my electronics (livewell, sonar) on the gas engine battery. I have never disconnected the wires to the engine when charging, and so far it has not done any damage that I know of. It is really up to you, if you think your main battery gets charged enough from the motor and you do not have any other loads on it like livewells and electronics, then a 2 bank charger would be fine. If you find yourself having a hard time starting after a long stop at your fishing holes, then maybe a 3 bank charger would make it easier to top off that battery at the end of the day. When I get home, my main battery actually takes some time to fully charge and I know it will be ready for my next trip. Hope that helps.

[ScottyJ]

I have the same setup in my old Champion, 24v trolling and my cranking battery. I run a 3 bank charger to make sure the cranking battery gets a full charge every time just to make sure I don't have any surprises when I get to the water. Plus I think its better for the life of the battery to keep it charged in between uses. As far as unhooking the battery I always do anyway just to make sure there is no drain on it while it sits. So everytime I charge I unhook the trolling motor and all the wires off the cranking battery.
If you want some more info call Charlie at Battery Systems he will hook you up. (916)997-2327


Scott

[Smile_n_Jax]

I run a 24V trolling motor and have the StaynCharge system on my truck and boat. This allows all three batteries to be charged while towing and running the big motor. I've had no problems with my batteries staying charged and I don't have to worry about connecting them to an outside charging source because where I store my boat there is no electrical.

[Chris B.]

Definitely get a charger that handles your trolling batteries and your engine starter battery. On-board chargers trickle charge the battery to keep it peaked so even if your boat sits for weeks you will always have a full charge.

No need to disconnect the on-board charger--they are specifically designed to not interfere with your motor's electrical systems.

If you need more help, let me know. I recently finished installing a 3-bank charger on my boat after doing a bunch of research. Works great and I'm very glad I did it.

[tunaman]

No need to disconnect the on-board charger--they are specifically designed to not interfere with your motor's electrical systems.

That's not exactly the question... the question is whether he has to remove the main battery cables while charging to prevent damage to his motor's rectifier.

I'd call Jordan at Anglers, or someone who really knows them well and has worked on the older models to be sure. The newer ones are designed such that you don't have to do so, but I certainly don't know if your would or not.

The other thought is to install a Perko switch in front of your main battery so that you can decouple it - that would serve the same purpose and also ensure you don't leak any energy (for instance on a LowranceNET bus or GPS antenna) while it sits.

Good luck!
Roger

[Chris B.]

That's not exactly the question... the question is whether he has to remove the main battery cables while charging to prevent damage to his motor's rectifier.Roger

I believe I did answer the question--on-board chargers will not damage the motor's rectifier so you can leave the DC charger leads connected. If you like, I can give you the technical reason (I have a degree in electronic engineering) but I figured it would sound like "blah blah blah..." to most here.

Also, to address another point made here, there is no need to disconnect the on-board charger DC leads for fear of current "drain" on the batteries. Properly-working chargers won't cause current drain on batteries, whether they are turned on or not. I'm happy to explain why if you like...

You may want to go right to the charger manufacturer with your questions if you're still uneasy about how you're going to be using it.

[Phil]

reason ! I had a older Johnson/Evenrude once , a 1990 or so. I came in one day and hooked battery charger to the cranking battery , which also runs all the electronics correct. In so doing this I blew the charging rectifier on the back of the engine, which there are two @ $ 150.00 so I was told anytime I hook a changer to my battery, to disconnect the cables going to the engine. So, I wondered if its so with on board charger also ??

Thanks

Phil

[Chris B.]

Phil,

It's hard to know why your regulator/rectifier blew without knowing more details. One thing I do know: generic (cheap) high amp car batt chargers could potentially send damaging voltage into your boat's electrical system if somehow the battery was momentarily disconnected during charging (could happen if you had corroded or loose battery connections).

All of the onboard marine chargers I looked at (Dual Pro, Minn Kota, etc) use safe current-limited and voltage-protected charging outputs. This should prevent damage to your regulator module.

The Dual Pro chargers even have temperature sensors in the charging leads that reduce the charge current as the battery's temperature increases.

Once you decide on a charger brand, it wouldn't hurt to call the mfgr and get their official go/no go on your setup before you buy it. I'm using a Dual Pro unit (model Three Bank Pro SE Extreme) for my 24v + 12v setup and it works great with my 13 year old 125HP Merc.

Other guys here may want to vouch for chargers they are using on older Evinrude motors.

[msilva21]

Hey Phil

Sounds like the problem could have been the charger you used. I"m guessing it was a portable one, some of those start out charging pretty high.
Could have been combo of older motor and the type of charger? The new on board chargers are pretty slick and should not cause any trouble, I installed a 3 bank chargers for 2 trolling and 1 cranking batteries on my old boat (newer motor though) and never unhooked anything..no problems.
When you decide on a brand, maybe talk to them to see if there are compatability issues with your engine. What about talking to the engine manufacturer? Maybe of some use, just to cover your bases.
I'm installing a new 2 bank on my new boat (thanks Phil ) tomorrow. Boy I sure miss that 24v trolling motor now that the new boat has a 12v. The 12v is all yours when I decide to make the switch, Phil.