have 3 12v batteries connected in series to make 36v that powers my trolling motor.i would like to maintain power system with solar power on 17' boat

[icecreaman]

have 3 12 v lead acid deep cycle batt. connected in series to create 36 volt system to power my ulterra trolling motor on my 17' boat.can any body tell me how to connect a solar panel to the system to maintain the batteries.do they have a solar charger controler that will charge 3 12v batteries equal from a solar panel. or do i have to use an electric battery charger. help

 

[snoobler]

Welcome to the forum.

I have moved your thread to Marine.

Charging 3 12V separately while in series is only common in the marine industry. You would likely need to look for a marine-specific solution.

Standard Solar PV and storage systems only charge the total voltage. Charging individual series components is rare enough that I've never heard of anyone doing it.

Many SCC can do 36V easily. IMHO, the solution *I* would come up with is a simple solar charge controller charging the 36V bank as a whole with 12V balancers working to keep them at the same voltage.

Will recommends several chargers here:

DIY Off Grid Solar Charge Controllers

Building a vehicle mounted solar power system? Let me help.

www.mobile-solarpower.com

You'd need to confirm that they support 36V

I recommend and use the following balancers for my 48V bank:

Affordable Electric Vehicle Batteries & Components from Electric Car Parts Company

Electric Car Parts Company is your one-stop-shop for affordable electric vehicle parts and components including batteries. Shop our selection and order now!

www.electriccarpartscompany.com

An important consideration is the amount of current the panel can provide.

Let's say your battery is a 50Ah battery. You would want to charge it with 10-15% or 5-7.5A. Since solar only products peak output at high noon on a perfect day, it's good to shoot for the high end. 7.5A * 14V = 105W, so a 100W panel should get you there. Note that when you put batteries in series, the Ah rating doesn't change, so 3X 50Ah batteries in series to make 36V still only has 50Ah.

 

[mudfunk]

have 3 12 v lead acid deep cycle batt. connected in series to create 36 volt system to power my ulterra trolling motor on my 17' boat.can any body tell me how to connect a solar panel to the system to maintain the batteries.do they have a solar charger controler that will charge 3 12v batteries equal from a solar panel. or do i have to use an electric battery charger. help

Did you ever figure this out? I have the same problem. Need to charge 3 12Volt, 66AH batteries that are in series and then I have 2 single 12 volts that are by themselves. I have AC chargers in the boat, but I need to charge when in storage without AC.

That brings up another question. Can I leave the AC chargers connected to the batteries when charging via Solar Controllers.....

 

[HarryN]

Did you ever figure this out? I have the same problem. Need to charge 3 12Volt, 66AH batteries that are in series and then I have 2 single 12 volts that are by themselves. I have AC chargers in the boat, but I need to charge when in storage without AC.

That brings up another question. Can I leave the AC chargers connected to the batteries when charging via Solar Controllers.....

Easiest way is to use 2 different solar systems - one for the 36 volt and one for the 12 volt.

Yes you can have multiple chargers attached to a battery pack at the same time. I do it all of the time.

Bogart engineering and others routinely do this.