preliminary electrical drawing for scrutiney

[dwh]

so is this right?

BATTERYBANK2.jpg

Eh..?

I take it that those two 12v doohickeys are bus bars?


I've edited your pic. Look at the power flow path:

The positive comes in to the right upper battery, then jumps to the left upper battery positive and then flows down to the left upper battery negative and then into the second (lower) series string. Then, it does the same thing on the lower two batteries only in reverse. In the lower string, the right side battery is in the path, but the left isn't.

What you have done there, is to cut two batteries out out of the power flow path. They'll act as tacked-on subsidiary helper batteries to the other batteries, but because they are not directly in the power flow path, the two batteries directly in the path will end up doing all the work.


Charging will do the same thing except the flow of the negative will turn left instead of turning right. Still, the lower left battery will be cut out of the power flow path.


As for the question about the isolator - the hot from the isolator should go to the positive bus bar, and then ground the negative bus bar to the chassis of the vehicle.


If you've got your bank wiring correct and balanced, then you should be able to just connect everything to the bus bars - batteries, solar charge controller, shore power charger, the wire from the isolation solenoid, fuse block, inverters - everything.

[dwh]

I appreciate all you do here as well as alot of folks...thank you for reading material

I see this as a the charger you talk about
http://www.amazon.com/DLS-55-AUTOMAT...pply+(12-volts


and the generator is 3300watt running

more solar will be added as time and $$ permits

Yup, that's the one. Only thing is - it doesn't do equalize. After 7 days at float, it will trigger what they call a "boost", which is really just running through the bulk and absorb stages again before dropping back to float. Of course, that requires that it be plugged in all the time. Otherwise, it will reset the 7 day timer every time you unplug it.

Still, the Iota with IQ/4 is extremely popular with the solar crowd who tend to run large banks of flooded batteries.

Also, by regularly pumping up the batteries to 14.8v, you shouldn't need EQ very often, if at all.


EDIT: But keep an eye on your water use. You will use more.

[dwh]

So, how to rig the batteries? Make two series strings, and parallel the strings at the bus bars. To keep everything balanced, make CERTAIN that the wire lengths on both strings are IDENTICAL.

Here's a cheeze-whiz diagram:

bank.jpg

[bansil]

I like cheez wiz...or did as a kid

Yes the 12V thingies are bus bars

I had it like your cheez wiz pic at first because it made the most scence

until I went looking at battery chargers and visited battery tenders web site FAQ area and saw that setup on the "hooking up" battery charger page
http://batterytender.com/resources/c...s-chargers.htm

and then that made scence

Would the "juice" not flow internally in the battery between +/- posts?

I am just trying to get a good grasp on this,because I have done this wrong in the past...it worked but not good or efficent

Thanks to post's here I now understand the importance of balance and using big enough wire etc.

So all 6 cables need to be the same; say with-in 1/4-1/2 inch?

Thank you again for all the Neewbe help

[dwh]

Would the "juice" not flow internally in the battery between +/- posts?

The power flow will follow the path of least resistance. That's almost always going to be the wire. It will have to flow through two of the batteries, because there is no other path.

Then there will also be a secondary flow to and from the primary batteries to the secondary batteries. That will be less than the primary flow, so the primary batteries will end up doing more work and wear out sooner.

[dwh]

until I went looking at battery chargers and visited battery tenders web site FAQ area and saw that setup on the "hooking up" battery charger page
http://batterytender.com/resources/c...s-chargers.htm

Figures, 9, 11 and 13 on that page will result in the abbreviated power flow path that I showed in the edited drawing of your pic.

They are however, the "quick and easy" method of hooking up multiple batteries. The quick and easy method is not always the best method.

[bansil]

Cool so I will go with my original plans for the battery hookup(the cheez wiz one)

And will look into the switch you mentioned also


Since we are on the battery topic:

The batteries will be bolted to the floor
,my plan was to build a vented box to house the batteries and then have the bus bars(machined copper with lugs etc) mounted to outside the box,with cables attatched on inside of box,with studs passing thru box to the bus bars,so box will be sealed from the cabin area

I was going to vent the top to the outside(with screen on it)

and run a vent(screened) into and along the bottom of the box to equalize the air movement

I was thinking 3/4in pvc tube
would this be enuf vent for 4 batteries?

Sorry for all the questions

[dwh]

So all 6 cables need to be the same; say with-in 1/4-1/2 inch?

Thank you again for all the Neewbe help

All 6 cables don't need to be the same.

What needs to be identical, is the resistance of the two series strings. So if you have 3' of +/- from the series string to the bus bar, and 1' from - to + in middle of the string, then the other string needs to be the same as that.

The closer the total resistance of the entire series strings are to identical, the better. Even a quarter or half inch difference in cable length can change the resistance measurably. Hell, one bad crimp can do that too.

Whichever string has the lower resistance, will end up doing more work and wearing out sooner.

It is of course, impossible to achieve perfection. People with big battery banks generally make it a habit to swap the batteries around to different positions once in a while.

[dwh]

I was thinking 3/4in pvc tube
would this be enuf vent for 4 batteries?

Probably not. More like 1.5" or 2". There is a formula for that. Lemme see if I can find it...


Try this:

http://bhs1.com/batteryroom/ventilation/

[bansil]

Were is the bow down Smiley?
Thanks