Battery Charger

[HPLou]

Good day,
I presently have a 2 battery SetUp ( house + starter for my 2 x 4.3lx ).
My battery Charger is a ProMariner Pro Sport 20plus, it's a 2 bank charger. I purchased this charger 2 years ago.
I want to add a 3th battery for accessories and was wondering if I could STILL use my present charger by wirering it a
certain way so that I could have 2 house and 1 starter battery?
Or I need to replace my Battery Charger with a 3 bank one.

 

[mjf55]

HP, it sounds like to plan to use 2 batteries in parallel for the house setup, and one battery for the starter. If that is the case, then you can use the same charger as you have. One bank will charge the 2 parallel batteries ( and it will take longer ) and the other bank will charge the start battery.

EDIT: similar discussion here http://forums.iboats.com/forum/gene...charging-trolling-motor-batteries-in-parallel

 

[HPLou]

mjf55 thank you for te link and your reply. (I have read but i am confused)

I will add a bit more details, if you don't mind;
I have a twin engine boat with a 1 ALL 2 OFF Switch.
I have presently 2 batteries, 1 Deep Cycle House & 1 Cranking for both engines.
I want to add an extra Deep Cycle battery for House.
I want to use my 2 bank ProMariner Charger.

I will be setting up my 2 House Batteries in Parallel;
Charger Bank-1
Positive Wire from Charger to Positive Bank of Bat-1
Negative Wire From Charger to Negative Wire to Bat-2
Charger Bank-2
Positive Wire from Charger to Positive Cranking Bat
Negative Wire from Charger to Negative Cranking Bat
That sets up the charger configuration.

Now For the Parallel Batteries connections;
Positive Bank of Bat-1 to Positive Bank of Bat-2
Negative Bank of Bat-1 to Negative Bank of Bat-2
Negative Bank of Bat-1 OR Bat-2 to ground

Is it possible to have Both House batteries being charged when both engines are running (during navigation)
How do I have to set up Battery Cables from alternators
OR does the 1 ALL 2 Switch will take care at ALL Position to recharge both batteries?
At the ALL Position, will the cranking battery (engines) will be also recharged by the Alternators?
HPLou

 

[JoLin]

<deleted>

 

[bruceb58]

You can put the two batteries in parallel and charge them with the one bank of the pro mariner charger.

The best thing to do to charge the house and the start banks while running the engine is to install an ACR, That way you don't have to do the battery switching game.

https://www.bluesea.com/products/761...12_24V_DC_120A

So you have all your house loads going to the house batteries? You have a separate switch for those?

 

[bruceb58]

I will be setting up my 2 House Batteries in Parallel;
Charger Bank-1
Positive Wire from Charger to Positive Bank of Bat-1
Negative Wire From Charger to Negative Wire to Bat-2

You left some connections out. Just make sure batteries are connected Positive to Positive and Negative to negative.

Out of curiosity, why do you have a house battery for each engine?

 

[HPLou]

bruceb58,
I only have 1 house battery and 1 battery to start both engines. I have 1 switch 1-ALL-2-OFF .
Position 1 on switch is for Starting engines
Position 2 on switch is for House/Accessories.
I want to add 1 more house battery for my 12v / 120v Norco Fridge that drains my House Battery.

 

[bruceb58]

So...at this point, you don't have anything separated? All loads, be it for the engine or for the rest of the boats, are connected to the common of the switch?

 

[HPLou]

exactly bruceb58
Nohing is separated. At Ancher My house battery is being drainned by my 12V/120V Fridge over the night, That does not make anysense.
I want to change this setup so I can separated the Fridge from all other accessories by adding 1 more house battery dedicted to the fridge.

 

[bruceb58]

I would keep what you have and get a set of 2 6V Trojan batteries for your fridge and it would have its own on/off switch between it and the fridge. I would wire up an ACR between that set of batteries and the common of your 1/2/all switch and another ACR between your start battery and that other battery you call a house battery.

I would buy a separate battery charger for the new house bank.

Those fridges draw a lot of power. Our boat had a monster 12V true deep discharge battery just for it. The 2 6V Trojans are way better.

Never draw down the batteries below 12.0V which is around 50%. Any more than that severely reduces its capacity.

 

[HPLou]

Thank you again bruceb58
2 x ACR's + 2 x 6V Trojans + 1 x Additionnal Switch + 1 x Additionnal Charger (1 Bank charger) = The solution
OK I'll go for that.
Can I have both 6V (for the fridge) New Batteries being charged by 1 Engine Alternator when running and
The other 12V (Acces + Starting) being charged by the other engine Alternator when running?

 

[bruceb58]

You could but it would require some creative wiring to isolate the alternator that charges only the Trojans. Would have the ignition turn on the field but would need the sense on the Trojans.