On Board charger and 12v system in parallel

[ordonyez]

Hi,

Ok I have three batteries in my boat.

1 Cranking for engine, electronics, pumps etc

2 deep cycle batteries for my 12V trolling motor.

I obviously have my two deep cycles hooked up in parrallel (pos to pos and neg to neg).

My question is I have a three bank battery charger. Do I need to hook up each battery seperatly? with the jumpers? As I understand it, the deep cycles in parallel are looked as one battery not two (with a bigger bank).

I looked in the instruction manual for my charger and it shows two 12V in parallel with only aconnection between the negatives but not the positives. Does it make sense to take off the connections between the positives????? Will they both still work for my 12V system?

Thank in advance.

 

[Silvertip]

Re: On Board charger and 12v system in parallel

It doesn't matter if you attach one output to each battery, or tie two of them together and attach them to one battery. The two batteries are already tied together so to the charger, the two look like one giant battery. The charger will work fine either way. The third output goes to the starting battery.

 

[hd883chopper]

Re: On Board charger and 12v system in parallel

It doesn't matter if you attach one output to each battery, or tie two of them together and attach them to one battery. The two batteries are already tied together so to the charger, the two look like one giant battery. The charger will work fine either way. The third output goes to the starting battery.

Silvertip,
I'm in a similar situation as the OP, just so I understand you correctly... my smartcharger (West Marine Charger) should recharge the deepcycle batts just fine while they're hooked together in parallel. I could connect the charger negative lead to Batt 1 negative and the charger positive lead to Batt 2 Positive.

This method of charging should charge each battery to its capacity? I was originally afraid that one may receive less of a charge (or over charge) due to interference from the 2nd battery.

Thx, hd.

 

[emoney]

Re: On Board charger and 12v system in parallel

Yes, the "maintainer" will keep both batteries charged just like they're one when they're wired in parallel. I just put the my cables on one battery and the charger will charge them both. I don't know about that particular brand of charger, but some of them won't charge if your batteries are below 10 volts, just as a point of information.

 

[Silvertip]

Re: On Board charger and 12v system in parallel

I want you to think about this carefully (this is instructional). Batteries in paralllel are interconnected with a length of wire -- right?? So what difference does it make if you hook the charger NEG lead to the negative terminal of one battery and the positive lead to the positive lead of the other battery? That terminal is still connected to the same terminal on the other battery by the length of wire. So it makes no difference where you connect the two leads so long as you don't reverse polarity. A single bank charger cannot tell which battery it is connected to in a parallel system. The two batteries simply appear as one larger battery.

 

[hd883chopper]

Re: On Board charger and 12v system in parallel

Yes, the "maintainer" will keep both batteries charged just like they're one when they're wired in parallel. I just put the my cables on one battery and the charger will charge them both. I don't know about that particular brand of charger, but some of them won't charge if your batteries are below 10 volts, just as a point of information.

I want you to think about this carefully (this is instructional). Batteries in paralllel are interconnected with a length of wire -- right?? So what difference does it make if you hook the charger NEG lead to the negative terminal of one battery and the positive lead to the positive lead of the other battery? That terminal is still connected to the same terminal on the other battery by the length of wire. So it makes no difference where you connect the two leads so long as you don't reverse polarity. A single bank charger cannot tell which battery it is connected to in a parallel system. The two batteries simply appear as one larger battery.

Excellent. Thanks for the info. That answers my question. I hope it also answers the original OP - Ordonyez's answers. Hope this wasn't perceived as a thread highjack since we're all talking multiple battery charging.

Thanks again!
hd