Battery move

[Scottc]

I have a 1970 35 MKII. Currently the batteries were moved to the center of the boat over the keel where the dinette would be. I want to get that space back. I installed a porta potti with a 5 gallon holding tank enclosed. I then removed the holding tank under the dinette seating on port side at the bulk head. I plan on putting my batteries there. I can fit 3 house batteries form the size I currently have. Now there are 4 and they are wired with two in series and the whole thing in parrallel. I want to just have the 3 in parrallel. I don't understand why they would have been wired the previous way. Any ideas? Also any ideas on what I am doing as good or bad. I love my boat and am trying to get it back to being pretty again. It has been a serious ocean racer with the previous owner and he did a great job setting the boat up mechanically.

Scott

 

[ctruax]

Batteries move

My Yanmar 2qm20H is mounted aft and four batteries under the dinette seat.
Three switches at the Nav station control 24v solar charging and two 12v cabin/engine banks.
I like having the the batteries forward to compensate CenterOfGravity forward to make up for Engine aft.
Some Ericsons installed lead in the bow to achieve balance.

 

[C.A. Fields]

I have a 1970 35 MKII. Currently the batteries were moved to the center of the boat over the keel where the dinette would be. I want to get that space back. I installed a porta potti with a 5 gallon holding tank enclosed. I then removed the holding tank under the dinette seating on port side at the bulk head. I plan on putting my batteries there. I can fit 3 house batteries form the size I currently have. Now there are 4 and they are wired with two in series and the whole thing in parrallel. I want to just have the 3 in parrallel. I don't understand why they would have been wired the previous way. Any ideas? Also any ideas on what I am doing as good or bad. I love my boat and am trying to get it back to being pretty again. It has been a serious ocean racer with the previous owner and he did a great job setting the boat up mechanically.

Scott

The batteries that you have are probably 6 volt. Two in series to give you the 12 volts and then those two banks in parallel to give you twice the amperage. The only way you can use 3 batteries and still keep your 12 volts is to buy three 12 v batts and connect them in parallel.
Cheers.

 

[ctruax]

6v 12v

I would agree for what you described: two 6v in series paralleled with 1 or more 12v to increase amp-hrs.
The voltage of batteries is typically twice the number of cell-fill-caps if you cant read and markings.
Also you could meter the voltages.