Connecting battery cables

[Adam1991]

Hi all, we’re finalising our 12 volt battery set up and running the pos & neg battery cables to the battery bank of 4 Trojan t105’s. 
 

We’re running the cable through both an internal and external isolator as well as having a mega fuse. 
 

Where should we connect the cables to on the battery bank itself? We’re not sure which battery of the 4 the pos & neg should connect to? 
 

thanks, 

Adam 

[David Mack]

http://smartgauge.co.uk/batt_con.html

[Bod]

http://www.smartgauge.co.uk/batt_con.html

This will tell you all there is to know regarding boat electrics.

It's writtern by an acknowledged expert.

 

Bod

[MtB]

9 minutes ago, David Mack said:

http://smartgauge.co.uk/batt_con.html

 

I can't see that working with T105 batteries.

 

6V aren't they?!

 

 

[Chewbacka]

For 6 volt batteries assume the individual batteries above are each two 6volt batteries in series.

[robtheplod]

something like this is they are 6v batteries?  

 

[Adam1991]

Thanks for all the replies! Yes they are 6v wired up to give 12v around 400ah. So would the drawing above suit? 

[David Mack]

53 minutes ago, Adam Mc Gowan said:

Thanks for all the replies! Yes they are 6v wired up to give 12v around 400ah. So would the drawing above suit? 

Rearrange @robtheplod's drawing to put battery 2 below battery 1 and battery 4 below battery 3 and you can see it's effectively the same arrangement as I posted from the Smartgauge site. So yes it's the way to go. And rob's version probably makes more sense in physical layout terms.

[Tacet]

2 hours ago, MtB said:

 

I can't see that working with T105 batteries.

 

6V aren't they?!

 

 

Depends on how many volts he would like to have?

 

[Peanut]

“robtheplod”, has two 6 volt batteries connected in parallel to give 12 volts, and then each pair connected in series to create a 12 volt bank.

[Tracy D'arth]

Just now, Peanut said:

“robtheplod”, has two 6 volt batteries connected in parallel to give 12 volts, and then each pair connected in series to create a 12 volt bank.

Not quite!  2 in series to give 12v then 2 pairs in parallel.

[Peanut]

Brain out of gear.

 

[MtB]

2 hours ago, Tacet said:

Depends on how many volts he would like to have?

 

12, as stated in the OP. 
 

 

[David Mack]

2 hours ago, Tracy D'arth said:

Not quite!  2 in series to give 12v then 2 pairs in parallel.

With the external connections taken from the diagonally opposite corners, to balance the load between the two pairs.

[robtheplod]

So just to double check... did i get it right?  

[Adam1991]

Hi all, thanks for your comments and recommendations. We wired the batteries almost exactly as above. Positive on the first terminal and negative on the last battery diagonally. All working! 
 

thanks, 

Adam 

[MtB]

7 hours ago, David Mack said:

With the external connections taken from the diagonally opposite corners, to balance the load between the two pairs.

 

Not that it matters a hoot in real life.

 

It's more technically correct but the end user would never tell the difference.

[Tracy D'arth]

9 hours ago, robtheplod said:

So just to double check... did i get it right?  

 

Edited February 5, 2023 by Tracy D'arth

[Tracy D'arth]

5 hours ago, Tracy D'arth said:

 

Yes you did, sorry, fell asleep answering.