hershey
Albuquerque,(fulltime) NM, USA
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From experience, no fancy numbers game involved, go with the 6 volt GC batteries.
But either will work of course.
hershey - albuquerque, nm
Someday Finally Got Here
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RoyB
King George, VA
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GP24 and GP27 indicates the physical size of the battery. Of course the theory is the larger the battery case the more AH it will produce. The GP24 physical size battery case is a good match for very large cores for 6V batteries but you have add two in series to get to 12VDC. With two GP24 battery cases sitting side-by-side you have a pretty big 12VDC battery case with heavy duty cores inside.
The beauty of the GC2s 6V and Trojans T105 6V is the large RESERVE TIME in minutes they have.
The T105 Trojan 6V battery has a 225AH capacity rating but the bigger thing to me is its RESERVE POWER capacity which is 447 minites which is 7.45 HOURS. This means the T105 6V battery will produce 25AMPS for over 7 hours. You have to hook two of then in series to get the 12VDC but 25amps for over seven hours is boss.
My GP24 SRM24 Interstate battery that came with my POPUP is only rated at 85AH and has a reserve power (RC) rating of around 140 minutes which isnt very long (that converts to a little over two hours drawing 25AMPS...) To make it through the night you need about three of these 12VDC batteries in parallel.
So the game plan is to find something that will produce the most AMP HOUR rating at 12VDC and will run the longest reserve time capacity in minutes that you can afford.
The golf cart batteries are built with just this in mind running the golf carts all day long chasing the little white balls. These are excellant batteries to use in the RV world but expensive... It appears COSTCO/SAMS CLUB have an excellant price for these GC2 6V batteries at less than $100 each.
I am really looking at going for two separate battery banks using two each GC2 6V batteries in each bank. This will give me 12VDC at 220AH and a RC of 25AMPS for 425minutes in each of the separate battery banks. I have radio units that I run alot out of the truck by itself andof course want to operate my OFF-ROAD popup off the power grid. So having the two separate bank banks will really help me out. When camping off the power grid I can connect the two separate banks together to give me 440AH capacity for 850 minutes or just over 14 hours. Cost wise to me this is hard to beat using the COSTCO/SAMS CLUB batteries at less than $100 each...
My two cents worth - Me no expert on any of this - I too am at the replacement point of my three failing five year old GP24 85AH 140RC Interstate batteries.
* This post was
edited 05/03/12 06:14pm by RoyB *
My Posts are IMHO based on my experiences - PM me
Roy and Carolyn
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smkettner
Southern California
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ken burke wrote:If we will do more boondocking I will get a 1000 or 2000 Honda generator.
1000 will only drive about 40 amps into the battery. Many RVs have a converter that is rated over 45 amps.
Also many converters are fixed voltage and amps will taper off quickly. Far better to upgrade to a three stage converter to keep generator time down to just 2 to 4 hours. When you head down this road post the brand and model of your converter for best recomendations.
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miatared
Toronto, Ontario
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I switched from a single G24 to 2 GC1 6V.
I bought 2 new battery boxes from JC Whitney for $11 each.
I am in Toronto and could not find these batteries at Costco in Canada so I got them from a US Costco (in Myrtle Beach). Bought them for less that $80 each, including core and hazardous waste fees.
All my lights are LEDs now.
I could not be happier - lots of Amp-Hours.
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dclark1946
Richardson,TX,USA
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wa8yxm wrote:Assuming the two six volt GC2 will fit in the space alloted
Two G-24's at about 75 Amp Hours each 150 Amp hours, since these are Marine/Deep cycle you should keep them at least 3/4 full giving you only about 45 usable amp hours.
.
You can get 100AH with the Trojan 12V SCS series Gr 24 battery for a total of 200 AH for a pair.
Dick
Dick & Karen
Richardson,TX
2007 KZ Spree 240RBS
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wa8yxm
Wherever I happen to park
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You still get more for less with a pair of GC-2's from Sam's club.
Best bang for your buck.
Best bang, Less bucks.
Nothin adds excitment like something that is none of your business
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ken burke
usa
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Joined: 09/15/2003
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RoyB wrote:
I am really looking at going for two separate battery banks using two each GC2 6V batteries in each bank. This will give me 12VDC at 220AH and a RC of 25AMPS for 425minutes in each of the separate battery banks. I have radio units that I run alot out of the truck by itself andof course want to operate my OFF-ROAD popup off the power grid. So having the two separate bank banks will really help me out.
You will have 2 banks of batteries. How do you plan to charge each bank, and using what charger?
thanks ken
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CincyGus
Cincinnati
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Just upgrade the Group 24 that came with my camper to a group 27. I don't do much off grid camping but if I start doing more, will likely add another group 27 or make the jump to 6v.
Benefits are pretty clear from what I have read that the 6v are much more forgiving of running them down lower and provide more AmpHours per $ (usually, read the specs). Negatives are height if you don't have the room.
Switching to LED lights and doing a little conservation, I'm pretty sure I can make the 27 work for me. I am planning on having a small genny a friend will lone me for the couple of 3-4 day/no electric trips I take a year and do have a three stage battery charger I can run off that for a few hours to recharge. At some point, I'll invest in solar but just not in the cards right now and want to make sure I am not going to upgrade/trade in my trailer any time soon before I make that investment.
2011 Silverado Crewcab 4x4
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RoyB
King George, VA
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Ken Burke wrote:You will have 2 banks of batteries. How do you plan to charge each bank, and using what charger?
I will use the SIACR smart relay BLUE SEA 7650 that will switch in my battery bank installed in the truck whenever the relay senses the alternator is in boost (14.4VDC) charge mode.
The battery bank in the trailer will use the PD9260C smart-mode converter/charger to keep this battery bank charged.
I will also have the capability using BLUE SEA 9001E four position battery switches to remomve the truck battery bank from the truck alternator system and connect it to the trailer charging system. I am hoping with using 2AWG cable for the longer battery cable run will be all I need to do to somewhat balance the charging currents when having both battery banks connected together. This might be my one challange doing this setup for the two battery banks. My backup plan of course is to charge each bank separately using my B&D portable charger from the generator.
Having two separate battery banks sure does solve the tongue weight on the OFF-ROAD POPUP trailer.
Still in planning stage but looking like I will get what I need. I keep running my truck start battery down when using my two way radios on missions and I think I have already hurt my truck start battery already as it doesnt seem to hold a good charge anymore. Everynow and then I have to put my B&D charger on the truck start battery in a WALMART parking lot and re-charge using my truck bed mounted Honda Generator haha... Just takes a few minutes to get going again
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pianotuna
Regina, SK, Canada
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Hi RoyB,
Peukert calculation on 450 amp-hours @ 25 amps draw:
3.5 hours to 20%
8.8 hours to 50%
14.1 hours to 80%
17.6 hours to flat dead
RoyB wrote:I would shoot for four GC2s or T105s - Two groups of 6V batteries connected in series will give 12VDC at 450AH with a RC capacity 894 minutes. This means you can pull 25AMPS from this battery bank for almost 15 hours.
Regards, Don
Kustom Koach Class C 28'5" 256 watts Unisolar, 875 amp hours in two battery banks 12 volt batteries, 2500 MSW watt inverter.
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