Advice Please

[cerebral]

Hello Guys,

Firstly I apologize if this is in the wrong section as this is my very first post here.

I wondered if this idea is possible. To be honest I thought I may have seen the original idea here but I can not find it.
Is it possible to charge several batteries using a charge controller connected to the bus bars instead of the battery direct,Then using equal size and length cable connected to each battery connected individually to bus bars so any battery that needs to be isolated or changed will not effect the other batteies.



I would then run the connections to the inverter from the bus bars, also should all the batteries have there own disconnect switch to make isolation easier and safer. I know there are other problems ie fuses but I thought I would ask about this first  .

Many thanks
Cerebral.

[Watt]

Yes, you could get by with this and yes to the disconnects for ease of use.  Just keep in mind, more connections, more resistance. 

[cerebral]

Thanks for the reply Watt,
Much appreciated mate.

Cerebral.

[jaysicle]

Hello,

I take it batteries 1-4 are the same voltage as one another, and the same voltage as the inverter requires ?
i.e.: what are you hoping to read across the red (+) and the blue (-)?
Parallel connection as this will give you 4X the Ah rating of one Battery. (Something you may already know).

In my set-up the charge contoller runs into / through a distribution block similar to this, but the current is ~10A max. from solar panels
(Bike input is not controlled - well it is limited though) allowing for relatively light cable (10g).

On the "out" end however, a completely different story.

Although I do not draw "1000W" out of my inverter at any given point, my 120V / 1000W inverter sees 12VDC in and therefore would require ~83A current flow to acheive that "1000W". Because of this - I have 100A fuses in line on both (+) and (-) from battery through a disconnect panel, to the inverter - all serviced with 3g stranded copper cable. Different fish than the I/P.

Rigid disconnect would be better (safer) than any type of wire hanging around. Battery switches are available for RV's (Princess Auto sells them here in Canada) and such - that disconnect through rotary switch - and might aid in changeout, but this should not happen regularily - i.e: mine should last 5 years or better - fingers crossed.

Apologies, without knowing your level of understanding - valuable advice is tougher to dispense than plain old advice - especially when the material /materiel is potentially lethal.  Not to dissuade - just to reinforce.

[SparWeb]

Welcome to the forum!

Good question, keep 'em coming.  Good answers already, too.

Keeping the number of wires down to a minimum increases reliability.
And you still can't mix types of batteries, or different ages, with this connection arrangement.
And you are confined to the voltage of the available batteries. 
Hopefully you don't intend to use 6-volt golf-cart batteries or you will have trouble finding a CC or an inverter to match.

If the distance between the batteries and the bus bar is very short, and the distance between busbar and the inverter is very far, then generalization about the cost of wire and total resistance may not be as sound.  Then do an analysis to see if there really is a penalty or not.

[tanner0441]

Hi

You don't say if it is solar or wind. If it is wind don't forget your charge controller must have a dump load option. Solar doesn't need a dump load.

Brian

[cerebral]

Hi Guys,
And thanks for all the replies.

It's all in the planing stage at the moment and is only a very small scale idea, I am planing to just use the power to run a few house lights and when there not on perhaps a small monitor/tv.

@jaysicle, The batteries are 12V 125AH and are of the same age and make. The Inverter will be no bigger than 600W, I wasn't really thinking of changing out the batteries often just in case of any problems I thought this may be easier that shutting everything down and dismantling the batteries if there were all tied together. The disconnect switches I've just ordered are the red key type that you turn to on/off. As for my knowledge level lets just say "minimal" .

@SparWeb, Hello and thank you for the welcome (I have been hovering around for a while in the wings but just signed up ) Thank you for your advice, I wont be mixing batteries or using 6V golf cart ones.

@tanner0441, I didn't mention the source as this is still in the planing stage. I bought four 12V 15W solar panels about a year ago there still boxed at the moment . I have been toying with the idea of getting a 600W pmg and perhaps utilising them both in the setup.

Thank you all again for your very useful advice and any help is always very much appreciated.
Cerebral.