Wiring 4 x 6v batteries for 12v

[Gibbo]

On the question of whether it is balanced or not, will it be possible to accurately test it when I'm connecting them?

 

If so, I can test all of these configurations - within reason - and stick to the one that proves best?

 

I can also post back here with any conclusions...

 

No simple test you can do. Not without some pretty expensive gear.

 

Pete's is perfectly balanced.

 

So is mine.

 

Mine passes the current through less links and is therefore, by definition, beter

[smileypete]

No simple test you can do. Not without some pretty expensive gear.

 

Pete's is perfectly balanced.

 

So is mine.

 

Mine passes the current through less links and is therefore, by definition, beter

Agreed, Gibbos is slightly better. Also would be a good retrofit for existing series parallel banks.

 

Doesn't need expensive gear to try out though, the freeware simulation program LTspice will do it easily enough.

 

cheers,

Pete.

[pistnbroke]

How much current are you expecting to flow in the cross link ? not much I suspect if all the batteries are the same age and type and fully charged . Job for the digital clamp on ammeter.

[Helga]

I've found this topic both very interesting and relevant to my situation. How would six 6v batteries be connected? Do the connections replicate with another two batteries below the four in the previous diagram?

 

Helga

[smileypete]

I've found this topic both very interesting and relevant to my situation. How would six 6v batteries be connected? Do the connections replicate with another two batteries below the four in the previous diagram?

 

To balance a bank of 3 batteries I'd do it like this:

 

 

Where the short links are the same length, and the ones next to the common points are doubled up.

 

So to connect 6x 6V batteries to give 12V, I'd do a similar thing to what we've discussed, with diagonal links.

 

Or if it's better to have them in a row of 6, just have 2 of the above banks in series.

 

 

Also when doing something like this:

 

 

Ideally the horizontal and vertical links should be the same length.

 

cheers,

Pete.

[Gibbo]

Doesn't need expensive gear to try out though, the freeware simulation program LTspice will do it easily enough.

 

Well it will if he knows what information to put into it. Which somehow I don't think he will.

 

 

Will someone redraw that with the diagonal link going the right way.

[WotEver]

Will someone redraw that with the diagonal link going the right way.

Here you go, Mr Grumpy

 

Tony

[WotEver]

To balance a bank of 3 batteries I'd do it like this:

 

Okay, so what am I missing?

 

As I see it, with that diagram both the outside batteries are going through one and a half links and the centre battery goes through one link (if you assume that two parallelled links equate to half a link).

 

Without the parallelled links each battery would go through 2 links - surely that would be better balanced, no?

 

Tony

[smileypete]

Okay, so what am I missing?

 

As I see it, with that diagram both the outside batteries are going through one and a half links and the centre battery goes through one link (if you assume that two parallelled links equate to half a link).

 

Without the parallelled links each battery would go through 2 links - surely that would be better balanced, no?

You gotta think about voltage drop, not just resistance.

 

cheers,

Pete.

[Gibbo]

Okay, so what am I missing?

 

As I see it, with that diagram both the outside batteries are going through one and a half links and the centre battery goes through one link (if you assume that two parallelled links equate to half a link).

 

Without the parallelled links each battery would go through 2 links - surely that would be better balanced, no?

 

Tony

 

The single links only have the current for one battery going through them. The double links have the current for two batteries going through them. So the volt drop on each link (or pair of links) between the batteries is the same.

 

It doesn't quite balance perfectly but it's damned close. So close it couldn't practically be improved upon without lots of messing around.

[bottle]

So.... To get this clear in my head, if we are wiring three banks the 'diagonal' links are not required but if only wiring two then the 'diagonal' link is.

[WotEver]

So.... To get this clear in my head, if we are wiring three banks the 'diagonal' links are not required but if only wiring two then the 'diagonal' link is.

It's got confusing, hasn't it?

 

The latest drawing from Pete is for parallelling three 12V batteries in a 12V system. If the batteries were 6v then you'd require two diagonal links joining the 6V pairs, but my brain's hurting too much right now to work out which way they'd go.

 

Tony

[smileypete]

So.... To get this clear in my head, if we are wiring three banks the 'diagonal' links are not required but if only wiring two then the 'diagonal' link is.

 

For a bank of 3 series pairs, something like this:

 

 

where the short horizontal and vertical links are all the same length.

 

That said, in most boats in might be easier to have the batteries in a row of 6.

 

cheers,

Pete.

Edited July 26, 2010 by smileypete

[bottle]

Thanks Pete and others.

 

I have six 12v wired for 24v, so will have a look and will probably change the wiring.

[Helga]

For a bank of 3 series pairs, something like this:

 

 

where the short horizontal and vertical links are all the same length.

 

That said, in most boats in might be easier to have the batteries in a row of 6.

 

cheers,

Pete.

 

That's answered my query about the configuration for 6 x 6v.

 

Thanks

 

Helga

[mudslide]

<!--quoteo(post=562747:date=Jul 26 2010, 05:10 PM:name=bottle)--><div class='quotetop'>QUOTE (bottle @ Jul 26 2010, 05:10 PM) <a href="index.php?act=findpost&pid=562747"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->So.... To get this clear in my head, if we are wiring three banks the 'diagonal' links are not required but if only wiring two then the 'diagonal' link is.<!--QuoteEnd--></div><!--QuoteEEnd-->

It's got confusing, hasn't it?

 

The latest drawing from Pete is for parallelling three 12V batteries in a 12V system. If the batteries were 6v then you'd require two diagonal links joining the 6V pairs, but my brain's hurting too much right now to work out which way they'd go.

 

Tony

http://

 

Ouch :- my heads hurting too !!!!

would it be too much to ask one of you fine experts out there how to wire 12 x 2v for 12 volts . Seems like it may not be as easy as first thought. They would have to be arranged in 4 banks of 3 to fit in the enclosure.

 

Just read Gibbo's article here (http://www.smartgauge.co.uk/batt_con.html) and came up with this .

 

[/img]

 

With 5 small and 1 large connection for each battery it seems balanced . Anyone care to comment ?

 

(I have a bitmap image but don't know how to load it.)

(Thanks Tony , I'vr uploaded a decent image now)

Edited August 27, 2010 by mudslide

[WotEver]

I have a bitmap image but don't know how to load it

http://www.canalworld.net/forums/index.php?showtopic=1633

 

Basically, you host your image on Photobucket or Imageshack (or other similar free image hosting sites).

Then you copy the shortcut to that image (the site will give you that)

Then when posting you hit the "Insert Image" icon and paste the shortut you just copied in step 2.

 

Tony

[mudslide]

http://www.canalworld.net/forums/index.php?showtopic=1633

 

Basically, you host your image on Photobucket or Imageshack (or other similar free image hosting sites).

Then you copy the shortcut to that image (the site will give you that)

Then when posting you hit the "Insert Image" icon and paste the shortut you just copied in step 2.

 

Tony

Thanks Tony , I'll edit my previous post now

[WotEver]

Thanks Tony , I'll edit my previous post now

That's better

 

With 5 small and 1 large connection for each battery it seems balanced . Anyone care to comment ?

Gibbo would like you to put diagonal links between the parallelled pairs... I'll see if I can quickly graffiti-ise your drawing.

 

Tony

[WotEver]

Here you go... complicated enough for you?

 

 

Tony

[mudslide]

Here you go... complicated enough for you?

 

 

Tony

 

Mmmmm thanks for that , sure is complicated . Would love to see some of those computer simulation stats on comparing the two .

[RLWP]

Mmmmm thanks for that , sure is complicated . Would love to see some of those computer simulation stats on comparing the two .

 

I don't think it's that hard. IIRC you just count up the number of cables in each path

 

Richard

[smileypete]

OK here is a way to do 4 x 3 batteries, using 2V cells in series/parallel to get 12V:

 

 

BUT...

 

So the diagonal links work as intended, the horizontal and vertical short links must be the same length.

 

I expect this won't be practical for 2V cells, so it would be better to leave the diagonal links out.

 

Edit: I wonder what batteries Julian got in the end?

 

cheers,

Pete.

Edited August 27, 2010 by smileypete

[GUMPY]

I wonder what batteries Julian got in the end?

 

I haven yet, may well leave it til spring as cash is short and being on the moorings 200Ah is just fine as the victron can cope with the load.......

 

However

 

It will be the 12v ones as the 6v ones wont fit my present battery boxes I did consider the 2v ones but the same applies.

Edited August 27, 2010 by idleness

[DHutch]

I would like a diagram of how to wire 48 2v 'traction' cells to make a 24v bank.

 

IM almost certainly going to continue to use four 12v leisure batteries. But i would like to see the diagram non the less....

 

 

 

Daniel