Understanding my solar power and batteries

[Rorzech]

My calculator says 12 X 215 = 2,580
There's no such thing as a 215 Ah golf cart battery last I heard.
I think you may be mistaking Cranking amps with amp hrs. and that's like apples vers. Oranges. Until you get your electrical terminology sorted out there's no point in me trying to get my point across to you. Eventually you'll figure it all out and you'll reach that ah ha moment. Good luck with that my friend.

[motion30]

I think you need to educate yourself there's two sizes of golf cart batteries 215 amp hours and 230 amp hours. Gc1. And gc2. Anybody that has research batteries knows that

[motion30]

You were showing you do not know what you're talking about. If a battery is 100 amps at 6 volts oh, and you link two together to make 12 volts still only have a hundred amps just at a higher voltage. If you do not understand that there is nothing I can explain to you my friend good luck with that

[Sailing Drummer]

My Duracells golf cart batteries are 215a (basically Dekka batteries made by East Penn). 12x215 = 1290 because they are 6 volt series/parallel.

[motion30]

And btw. anybody has any passing knowledge of batteries knows that golf cart batteries are not rated in cranking amps

[StuM]

Originally Posted by motion30

You were showing you do not know what you're talking about. If a battery is 100 amps at 6 volts oh, and you link two together to make 12 volts still only have a hundred amps just at a higher voltage. If you do not understand that there is nothing I can explain to you my friend good luck with that

If you don't know the difference between amps and amp hours, it may be advisable to find out before commenting further in this thread.

[john61ct]

Originally Posted by motion30

I have 12. X215 amp batteries. 1290 amps. Check my math. No?

Yes that is correct.

To much sniping here guys, be pleasantly helpful please.

Each GC connected in series adds AH. So 6x 215AH is 1,290AH @6V

Then paralleling the two strings gets you to 12V, but AH does not double.

[StuM]

Originally Posted by john61ct

Yes that is correct.

To much sniping here guys, be pleasantly helpful please.

Each GC connected in series adds AH. So 6x 215AH is 1,290AH @6V

Then paralleling the two strings gets you to 12V, but AH does not double.

WTF?


"connecting in series" doesn't increase Ah. 6 x 6V batteries in series = 36V. Do that and you'll blow everything on the boat!


"paralleling" doesn't increase voltage. You've just got more AH at 36V to do more damage.

[Sailing Drummer]

Sounds to me like he has 6 strings of 2x6v batteries, each string is connected in series, then the 6 strings are connected in parallel.

[john61ct]

Yes LOL got it opposite good catch Stu 8-)

Serial then parallel , and

3-4 strings max

is best to prevent balance issues

[JohnT]

Just a quick question to the OP. How many panels do you have and how are they wired? Are they all wired in parallel or do you have them wired in series and parallel? And what is the VOC of each panel?

[charris]

Originally Posted by Unity

Batteries take higher charge when batteries are less full. For most batteries, above 80% charged is both unnecessary and inefficient. Basically the solar charger will stop sending current (meaning you are wasting available power) as you go to absorb and then even more so at float. Your configuration sounds awesome!

It is imperative for battery longevity and for max reserve AH to fully charge the batteries. Don't rely on the SOC (state of charge) meter that you have on your battery monitor. They can be very inaccurate. The only way is by measuring the specific gravity - you want at least 1.265 for a full charge. A hydrometer will work, a refractometer is better.

If you are not fully charging you are going to be getting sulfate building on the plates and not only shorten the life of the batteries but you will reduce the surface area so will have less and less reserve time. At least once a week you need a full charge and you should also equalize once a month or so to stir up the electrolyte and "boil" off the sulfate. Once you reach 1.265, you can drop from absorb to float, so if you have control of your absorb time, you may be able to reduce it and then you will go to float more often. If you haven't equalized for a long time, you will see an immediate improvement upon completion of a full equalization - perhaps 2 hours or more at equalize. Make sure your electrolyte levels are full before and after starting.

[Cadence]

Originally Posted by Rorzech

My calculator says 12 X 215 = 2,580
There's no such thing as a 215 Ah golf cart battery last I heard.
I think you may be mistaking Cranking amps with amp hrs. and that's like apples vers. Oranges. Until you get your electrical terminology sorted out there's no point in me trying to get my point across to you. Eventually you'll figure it all out and you'll reach that ah ha moment. Good luck with that my friend.

[john61ct]

Originally Posted by Rorzech

There's no such thing as a 215 Ah golf cart battery last I heard.

actually it's a very common size

[john61ct]

Originally Posted by charris

Don't rely on the SOC (state of charge) meter that you have on your battery monitor.

True

> The only way is by measuring the specific gravity

False. In fact SG to be very accurate requires isolated resting time, 24-72 hours.

For 100% SoC most accurate and very easy is to measure trailing amps, compare to batt mfg spec for endAmps.

Then the AH counting BM can be reset to 100%, and if properly calibrated, will be "good enough" on the way down to ensure you don't deplete too far.

Advantage is these work just as well with sealed as with FLA.

Equalization should also follow protocol spec'd by the maker.