Draft of power system

[Jmooney]

Lots of folks in here with experiance in power system design - Attached is my draft for the build in my 5er.

Appreciate any feedback

[waynem]

I would suggest adding the ability to disconnect the solar panel from the charge controller. You want to be able to connect to the battery bank first, then to the panels.

[Jmooney]

Or just move existing ahead of controller, or both?

[Jmooney]

based on advice from forum:

Added 50 amp surge protector at shore power source
Moved discconnect above Solar controller
Added 30 amp diode to protect solar panel
Noted negative connection between converter and battery array

[waynem]

The disconnect between the array and controller is good. I am figuring out my system as well and planning a disconnect/fuse in both places. I've seen some that use a fused air conditioner disconnect that will provide the fuse and disconnect for both sides. You may want to check them out.

A couple other things. Make sure your charge controller is as close to the batteries as possible. Like 6 feet of wire length or less. And watch your wire sizes. For one panel 10 AWG is probably fine depending on the length. Maybe larger from the controller to the batteries. You want very little voltage drop there so the controller is seeing close to the actual battery voltage. Play with some on-line voltage drop calculators. Try to get your total voltage drop from panels to batteries to <5%. Smaller drop is better but it's a trade off with larger wires that are expensive and more difficult to work with.

I've learned a lot by reading http://handybobsolar.wordpress.com/t...ging-puzzle-2/ You might want to check it out.

[Jmooney]

Handy bob is great. I've read his stuff and several others.

All of my hardware is is within a foot or two of each other. The battery array is in a self contained and vented battery box, so safe from gas/ electrical issues. ( see other post of mine about that build)

The wire from solar panels comes with the kit, and I haven't scoped out the run yet, but will keep it as short as possible

Thanks

I'll post some final pics and diagram when I'm done in a few weeks

[Seann45]

The only change I would make from the diagram you have is how the power goes in and comes out of the battery bank. Pos in in the upper left Neg in the lower right.. THEN Pos out in the upper right and Neg out in the lower left. This makes every battery in the bank work at the same pace. I have had this setup on my battery bank for the last 6 years. This winter I camped with several electronic gurus and asked them about the way I had it set up. They both told me it was the preferred way to do a setup.

[Jmooney]

I did read that the resistance in the stud to stud wiring can cause slight differences in battery conditions, but it seamed minimal.

For the sake of the drawing that someone else might look at one day, I'll update to reflect that preference.

Thanks

[Mustang65]

Here is a link to my JOF album that gives you the best possible connection for multiple parallel batteries. It takes a little more wire, but the results are worth it.

http://www.jaycoowners.com/forums/album.php?albumid=371&pictureid=1972

It is as close as you can get for an equal drain on all the batteries in parallel. If you go to my album you will find a 3 page write up explaining the differences and even shows levels of drain on each battery in the hookup, when a load is applied. It is very interesting. I also have a wiring diagram for my solar/TT electrical on the link below (as always, it is a living document)..

Nice job!!
Don

[Jmooney]

Wow! The math behind method number 1 is quite startling.

Now you have me wondering how I actually wired up the four batteries.

From the document, method number 2, while not optimal, seams simple enough for anyone to implement.

This document needs to be promoted more often. I bet a bunch of folks are the same as I was, and think its really a general buss of power.

Thanks Don

[Jmooney]

Updated again, but I think I'm in home stretch

* Noted separate and vented battery box ( as all switching is located in same power room)

* Moved + & - battery connections to opposite ends ( Thanks Mustang65. You need to read his docuemnt on unbalanced load!)

* Oriented diode correctly

[Seann45]

Your power in is now done right.. BUT I would suggest that you move the power out to the opposite ends of the battery bank.. This would force the power to go through the batteries even better..

[Jmooney]

I thought that I was achieving that by placing positive and negative demand on opposite ends, in keeping with article from Mustang65. I'll re-read what he posted.

[Seann45]

fine tuning is placing the draw at opposite ends from the input.. this causes 100% of the batteries to be used.. Kind of like racers waxing the race car to get that extra .0001 out of it..

[Mustang65]

Originally Posted by Seann45

fine tuning is placing the draw at opposite ends from the input.. this causes 100% of the batteries to be used.. .

Seann45,
The first battery on the load side of the battery bank will absorb most of the drain. The attached battery load study breaks down the amps by each battery in the bank.

You can read the entire study posted in my albums. It is amazing at the difference on each battery.

Don

[Jmooney]

So I think I am now at " method 2 ", and while not optimal, much better than all load at one end as I originally depicted.