First, I am no expert on this subject, here is a link for a good read from an expert:
http://www.marxrv.com/12volt/12volt.htm
Read both part one and part two.
My system is a 6 volt battery bank, wired to produce 12 volts. I have 6 Golf-cart batteries, around 220 AH each, for a total of 660 amp hrs. The six volt batteries are wired to give 12 volts, so each 2 batteries are 220 amp-hrs totaling the 660. This link explains it a little better:
http://www.solarrvpanels.com/index.p...ries-properly/
I ran 2 tests, the first with a weak battery, since they are all hooked together, one bad battery pulls down the rest. That is why it important to use the Hygrometer to do a specific gravity test on your battery bank. No matter if you have one, or 6 batteries. If you have a sealed battery, obviously this will not work. You can take a good voltage meter and it will read the proper voltage, but if the test comes in with a low S.G. reading, the battery is weak.
The second day was with all good batteries, I am glad I found the bad battery here at home, rather than on the road. These batteries are $82 plus tax each. Sam’s Club replaced my year-and-half battery free with no pro-ration, pretty good warranty.
Link to Hygrometers: http://www.amazon.com/mn/search/?_encoding=UTF8&keywords=battery%20hydrometer&tag= ouradve-20&linkCode=ur2&qid=1325945215&camp=1789&creative= 390957&rh=i%3Aaps%2Ck%3Abattery%20hydrometer
Test first day, we had a 23 amp constant load on the batteries, a small refrigerator, the one living room ceiling fan, battery charger for a drill motor, a radio, and the satellite Direct TV receiver. (Everyone will have a different load, depending on your life-style, but the small reefer will cover computer use, and other small loads)
There are also ‘Phantom’ loads, the Propane detector, 3 T.V. sets, (Instant on) these loads are small, but must be figured in when setting up a system.
This is an average light load a camper may have on any given day with a Propane reefer and Propane water heater.
11:38 A.M. all but the small refrigerator: 11 amps. 12.5 volts
11:54 A.M. same load 12.3 volts
12:38 P.M. Plugged in the small refrigerator 23 amps. 12.3 volts
2:20 P.M. same load 12.3 volts
4:35 P.M. same load Now the battery is at 60% 12.2 volts
6:00 P.M. same load Now the battery is at 45-50% 12.1 volts.
Suspended test, but I still had time to go and battery life left.
At 11.75% battery, you are in the ‘caution’ zone, it is best to recharge then.
Next day, all good batteries, battery bank reads 12.6 volts.(100%)
11:17 A.M. 2 ceiling fans, small refrigerator, chest freezer, radio, satellite receiver, small battery charger as loads; 25 amps.
1:00 P.M. same load all day. 12.4 volts 80%
1:42 12.3
2:14 12.2 60%
3:55 12.2 60%
4:48 12.06 50%
8:22 P.M. 12.0 45%
9:22 11.9 40%
10:35 11.75 30%
Test suspended, 11.75 is in the caution zone, recharge needed.
Lights went on and off as we entered the trailer, the compressors cycled on and off on the refrigeration equipment, and we tested the fans on the rooftop A/C units twice, all ran fine on the 11 hour Inverter test.
I asked our professional Boon-dockers for input, but they all must be 'Off grid' and saving that precious batter power.
I have -0- experience in this matter, but am willing and able to learn.
Whether you have solar or generators, the usage part of camping without the power grid is the same pretty much the way I see it.
Linear Mode
