I am thinking of upgrading my batteries on my Sandpiper 303BH to 2 AGM 12 volt batteries. Just looking for some advice on what type, size, series etc... and do I need to change my inverter/charger or any modifications for maintaining them?
I am thinking of upgrading my batteries on my Sandpiper 303BH to 2 AGM 12 volt batteries. Just looking for some advice on what type, size, series etc... and do I need to change my inverter/charger or any modifications for maintaining them?
Your converter/battery charger built in (not inverter) will read the two batteries (Not four as in diagram) as one big battery and charge your two batteries as one just fine as is. 2 x 100 amp hour batteries wired like this will give you 200 amp hour of 12V DC battery power.
While AGM batteries are pretty cool; for capacity, wet cell batteries have them beat.
Check the Amp Hours of two of the best AGM batteries available and compare it to ONE deep cycle 12 volt wet cell battery. I have done this comparison many times on the forum. For half the money you can get twice the "hang time" with wet cell technology.
What model are you thinking about getting and I will do the comparison for you.
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Lou & Freya the wonder dog
2008 GMC Sierra 3000HD Allison Duramax
2019 Flagstaff 8529FL
I had to replace the battery in my 2005 wildcat yesterday. I had seen that the factory? installed battery was not a deep cycle type battery.
I called my dealer to get some info on battery types and learned that deep cycle batteries are more expensive and heavier than cranking power type batteries. AND since I keep my rv plugged in while it is parked in my driveway, it is getting a trickle charge all the time. I learned from my dealer that deep cycle batteries get a charge memory, where the others do not. By the way, I bought my rv in September 2004 and the factory installed battery lasted me until now.
I think your dealer needs to go back to battery school
Quote:
Originally Posted by still-learnin
I had to replace the battery in my 2005 wildcat yesterday. I had seen that the factory? installed battery was not a deep cycle type battery.
I called my dealer to get some info on battery types and learned that deep cycle batteries are more expensive and heavier than cranking power type batteries.
True, they are more $$ and are heavier because deep cycle batteries have much thicker plates compared to starting batteries. The major difference between a true deep cycle battery and others is that the plates are SOLID Lead plates - not sponge. This site explains it well - Deep Cycle Battery FAQ
AND since I keep my rv plugged in while it is parked in my driveway, it is getting a trickle charge all the time.
Exactly. The converters in today's RVs offer three-stages. A common converter is the 55amp WFCO 8955. The "float mode" or third stage provides a trickle charge when there has been no load for two days.
I learned from my dealer that deep cycle batteries get a charge memory, where the others do not.
Lead-acid batteries (flooded/wet, gel and AGM) do not have a memory effect. This is an expensive myth because some people then believe that their battery needs to be fully discharged before recharging. This can only lead to early battery failure.
By the way, I bought my rv in September 2004 and the factory installed battery lasted me until now.
I would say you kept good care of your battery .
As explained in the FAQ I linked to above, how any battery is used, how it is maintained and charged, temperature, and other factors will effect its lifespan.
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Scott
DW, 3 Kids and our Goldens
2012 Shamrock 233S
2008 Toyota Sequoia 5.7L 4WD
While AGM batteries are pretty cool; for capacity, wet cell batteries have them beat.
Check the Amp Hours of two of the best AGM batteries available and compare it to ONE deep cycle 12 volt wet cell battery. I have done this comparison many times on the forum. For half the money you can get twice the "hang time" with wet cell technology.
What model are you thinking about getting and I will do the comparison for you.
Thanks herk for the attached image and manuals! I just purchased a new trailer and was wanting to add a second battery. I knew to connect the two batteries + to + and - to - by the same lenght cable, but didn't know if I connected the trailer connections back to the batteries using the + and - on battery "A" or use the + on battery "A" and the - on battery "B".
Another question, I carry a small portable generator and a 12V battery charger when boondocking. If I use the battery charger, do I connect the clamps from the charger to the + and - on one battery (battery "A") or do I use the + from "A" and the - from battery "B"?
Thanks herk for the attached image and manuals! I just purchased a new trailer and was wanting to add a second battery. I knew to connect the two batteries + to + and - to - by the same lenght cable, but didn't know if I connected the trailer connections back to the batteries using the + and - on battery "A" or use the + on battery "A" and the - on battery "B".
Another question, I carry a small portable generator and a 12V battery charger when boondocking. If I use the battery charger, do I connect the clamps from the charger to the + and - on one battery (battery "A") or do I use the + from "A" and the - from battery "B"?
To charge (discharge) both batteries equally, the total resistance to include internal battery resistance must be the same.
Connecting the positive of one battery and the negative on the other battery with equal length jumpers between the two positives and the two negatives will do that.
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Lou & Freya the wonder dog
2008 GMC Sierra 3000HD Allison Duramax
2019 Flagstaff 8529FL
Thanks, I wrote that before I started researching batteries. I'm looking at changing to duals group 27's if I have the room. My battery location is on the tongue behind the tanks. My current is an Interstate deep cycle unknown group. Just was thinking out loud. My wife works for the dealer we bought our CC from so I may use her discount. Will know tomorrow. Thank you for the insight.
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2007 Ford F250 4x4 Harley-Davidson Powerstroke
2006 Cedar Creek Silverback - 35 LRLBS
(2012 -11) (2013 - 10 so far)
We never "dry camp"-always go to a site with full hookups. I got my fill of primitive camping many years ago.
Seems that either my dealer gave me some ancient info, or I misunderstood him.
Looks like deep cycle is what I should have bought. I read the suggested articles you provided. I get the impression deep cycle batteries are perfect for dry camping. Assuming I have is with a deep cycle battery installed in my rv, will it provide ample power to keep my refrigerator running for say, 8 hrs-while being towed to my next destination? with the previous battey, my refrigerator was hot by the time I got to my destination. I thought my rv pigtail connected to my truck would have kept it running, but it seems all that thing does is operate my electric brakes and outside rv lights (brake lites, turn signal lites and running lites).
Lee
Still-learnin, the pigtail that plugs into the truck will only control tail, brake and clearance lights, turn signals and electric trailer brakes. Your refrigerator only runs on shore power when at camp, and propane for traveling or camp. I too am still getting good tips. I have a group 24 deep cycle battery on my TT that is in need of replacement and am looking at going with two group 27 deep cycles. The amp/ hours of groups 24/27 (Interstate batteries) is 84/96 respectively. For my application that would put me at 192 amp/hours. Hopefully this helps.
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2007 Ford F250 4x4 Harley-Davidson Powerstroke
2006 Cedar Creek Silverback - 35 LRLBS
(2012 -11) (2013 - 10 so far)
We never "dry camp"-always go to a site with full hookups. I got my fill of primitive camping many years ago.
Seems that either my dealer gave me some ancient info, or I misunderstood him.
Looks like deep cycle is what I should have bought. I read the suggested articles you provided. I get the impression deep cycle batteries are perfect for dry camping. Assuming I have is with a deep cycle battery installed in my rv, will it provide ample power to keep my refrigerator running for say, 8 hrs-while being towed to my next destination? with the previous battey, my refrigerator was hot by the time I got to my destination. I thought my rv pigtail connected to my truck would have kept it running, but it seems all that thing does is operate my electric brakes and outside rv lights (brake lites, turn signal lites and running lites).
Lee
Lee,
I think in your case, any group 24 battery will do. It doesn't have much call on it when you're on shore power, except to provide a boost for slideout operation as needed.
"Deep cycle" is thrown around a lot, but in practical terms just means a battery than can provide many hours of low-amp use and deeper discharging than a starter battery, which does well with very brief high-amp use such as starting your truck. If you don't ever plan to discharge the trailer battery deeply, such as with dry camping, than save your money and go group 24.
The fridge is a different issue it sounds to me. As mentioned, it will run on propane while towing using a little 12VDC. Assuming you do not have a three-way fridge like in a popup, then you only have AC or propane to cool. Gas is usually a more effective way to cool a fridge than AC so I'd guess that you either did not turn the fridge to auto (so it can switch to gas when you unhooked from 120) or its not working properly (no propane or prob with fridge).
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Scott
DW, 3 Kids and our Goldens
2012 Shamrock 233S
2008 Toyota Sequoia 5.7L 4WD
1) Not charging the battery while towing from the Tow vehicle. The pigtail (assuming you have a 6 or 7 pin Bargman type plug) will most certainly provide 12VDC charging current and voltage to your camper. If you are not getting charging voltage you should check your truck's manual for the location of the fuse that powers the charging line. In my Chevy product, the red wire was located UNDER the fuse block and even though the fuse was installed in the fuse block, the wire was not connected at the factory; nor was it connected by the dealership when it was delivered.
I am told this is not unique to Chevy or GMC.
2) Your fridge will run on about 1.2 amps of DC current and a fully charged deep cycle (even the cheap OEM Dual Purpose one they use) should outlast the propane supply of most campers even without the charge line connected. So if you have a good battery and the propane on, your beer should be frosty cold when you arrive at your destination.
3) It is CRITICAL that the "defrost switch" be turned off when using the battery to run the fridge (it is a 12 volt HEATER). The high draw of the defroster will kill a typical RV battery in about 10 hours. In my fridge it is a black rocker switch in the front top of the freezer compartment. Coupled with no charge line from your truck, this switch being ON will cause your ice cream to run all over the floor after an 8 hour drive.
4) How you pack your fridge also contributes to how it cools. An overly crowded fridge (like at the start of a trip) will reduce air flow over the fins in the cooler section. This will cause hot spots in the fridge cooler and freezer sections.
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Lou & Freya the wonder dog
2008 GMC Sierra 3000HD Allison Duramax
2019 Flagstaff 8529FL
Just because AGM batteries cost (a lot) more, doesn't mean they are an upgrade. They have less capacity than a comparably sized wet cell battery, and they don't last any longer than a properly maintained deep cycle battery.
The operative words are "properly maintained." Those who are too lazy or too uninformed to do battery maintenance should spend the extra cash and buy AGMs. For the rest of you, save your money.
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2011 Silverado 2500HD Duramax, 4x4, crew cab, long bed
Palomino Puma 253-FBS, 27' 5th wheel
1994 19' Class B on Chevy chassis
The operative words are "properly maintained." Those who are too lazy or too uninformed to do battery maintenance should spend the extra cash and buy AGMs. For the rest of you, save your money.
AGM batteries are much much more expensive a replacement than battery costs indicate. AGM batteries have different charging characteristics than wet cell batteries and would require a replacement charger/converter (additional cost) or a separate charger and some rewiring to allow correct recharging.
Between my RV and astronomy and amateur radio (ham) hobbies I've spent lots of time working with different types of batteries. The rules I've followed that have worked successfully for all battery types are:
1. Learn all you can about the type of battery you intend to use.
2. Always use a charger designed for the battery to be recharged.
3. Maintain your batteries at regular intervals.
I've discovered that even the little AA and AAA Alkaline batteries need occasional maintenance. The metal that manufacturers use for the end caps will oxidize and form a high resistance layer that impacts battery performance. This is most noticeable in LED flashlights that use a single battery.
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