Community Forums

John Hilley · 02-05-2017, 09:05 AM

Quote:

Originally Posted by LeeB

Thanks you all have giving me some great information, the electric is Mama's wish. I like the down comforter and I have a feeling I will be winning this one.

...

I have measured and I do have room for 4 6v except I have to trim the top about 1 inch to make room for height... So far the Costco batteries are winning although I may check into 2 12volt and see....But I do like the idea of having 800+ah I can get with 4 6volt, not sure how many ah I can get with 12volt

Thanks LeeB

You would only be getting 416 aH with the 4 x 6 volt batterries. To get 12 volts you have to have two series connected batteries and then connect them in parallel. In a series connection the voltage is the sum, but the current is only that of the smallest battery.

Old Scout · 02-05-2017, 09:16 AM

All good input but the real answer is: "it depends"......You didn't mention it but assume you have an RV [propane] fridge. Besides having a residential fridge, running the inverter [1000-2000 watts] all night can consume a lot of AHs, even if its only for just a blanket. Solar helps during the day [obviously] but getting thru the night is the challenge. Assuming only 50% available, 220 total AHs isn't much, 440 is good, but 660 AH seems to be a good all around capacity. Yup--you can survive on much less but you are always seem to be looking for ways to conserve.
Have used Costco and Sam's bats for a couple cycles now--but went back to Trojans this time--if you dry camp much, seems like you get what you pay for with bats--IMHO.

computerguy · 02-05-2017, 09:18 AM

Quote:

Originally Posted by LeeB

...But I do like the idea of having 800+ah I can get with 4 6volt, not sure how many ah I can get with 12volt

Thanks LeeB

800 AH from 4 6v batts?
Did you mean 400?
Or 8 6v batts?
Or are these not the typical GC/GC2 batts many people use?

Todd727 · 02-05-2017, 04:47 PM

Quote:

Originally Posted by LeeB

But I do like the idea of having 800+ah I can get with 4 6volt, not sure how many ah I can get with 12volt

Thanks LeeB

You will get 205ah from each PAIR of batteries connected in series. So, with four batteries, you will have two pairs, or 410ah, not 820ah.

wa8yxm · 02-06-2017, 07:19 AM

I would go with Sam's or Costco GC-2's and go with double the number however. As others have said, running down to 10 volt, NOT GOOD, though I am not proud to say I did it several times over the 9 year life of my original batteries. (The new ones I keep fuller).

But doubling the number of batteries MORE THAN doubles the run time, and with the electric blanket you may find it nice to have more battery.

I more than doubled my battery bank, which is why I don't run 'em down that far as often now days.

LeeB · 02-10-2017, 10:00 PM

Quote:

Originally Posted by computerguy

800 AH from 4 6v batts?
Did you mean 400?
Or 8 6v batts?
Or are these not the typical GC/GC2 batts many people use?

Not sure I understand, do you NOT add up the ah's? It says 210 ah

twinboat · 02-10-2017, 11:13 PM

No, you only add up AH when you wire in parallel.

When using 6 volt batteries to make 12 volts, you add the volts, but not the AH.

2, 210 AH 6 volt batteries = the same as 1, 12 volt 210 AH battery.

4, 6 volt batteries will give you 420 AH

twinboat · 02-10-2017, 11:14 PM

Duplicate

LeeB · 02-11-2017, 09:04 AM

Quote:

Originally Posted by twinboat

No, you only add up AH when you wire in parallel.

When using 6 volt batteries to make 12 volts, you add the volts, but not the AH.

2, 210 AH 6 volt batteries = the same as 1, 12 volt 210 AH battery.

4, 6 volt batteries will give you 420 AH

Oh OK.... Thanks

wa8yxm · 02-11-2017, 09:12 AM

One comment on the different GC-2 Batteries.

I've seen several ways to rate the Amp Hours. Fact is though there are SOME differences between different versions of the GC-2.. The differences are not all that great.. I Usually say they are 220 +/- 10 Amp hours, that is less than 5% so it's not worth mentioning.

Wal*mart rates batteries at the 1 amp rate. So a Group 24 lasts over 100 hours at 1 amp.. But at the 20 hour rate it's only 73 amp hours..
You can look up the effect of speed of discharge on battery capacity but the faster you drain, the faster still they run down... I can never recall the spelling of the effect.

You need to insure all the ratings you look at are the same method... For there is no "Standard" but here in the forums we usually use the 20 hour rate.

I'd go with Sam's or Costco GC-2's. or, well, since I have not a membership in those outfits any more... DEKA was not much different than GC-2 times 2 plus membership renewal so I went with DEKA. G-20s

The G-20 is a 230 Amp hour box.. and the difference in my case is astounding, for one thing where my older 215 AH boxes needed watering every year (once a year when new) the new DEKA's .. Well I will admit they are not the ONLY batteries in the box ( now have around 550 Amp Hour total capacity) have not needed watering yet and they are going on 4 years old. I will top 'em off later this month need it or not.

Converter is a Progressive Dynamics 9180 with Wizard.

Why is this? Well, I suspect it is because 80 amps is a bit less than 15% of the total 20 hour capacity,,, where as the proper max charge (per Xantrex) for flooded wet or Maintenance free or other than lifeline AGM is 30%, but the slower re-charge = Longer battery life and less water consumption.