Battery draining question
I'm pretty new to RVing. We have been inveterate tent campers, but last fall purchased a used '07 (or '05 - somewhere around there) hybrid travel trailer (Jayco JayFeather 19-H) so I'm pretty new to ...
Forum Discussion
Well, thanks for the quick replies. Clearly I have a lot to learn about RVs and batteries - especially the useful voltages.
There is one thing that is still bothering me though and that is the conflicting information I have seen about deep cycle batteries. First off, there is a monitor panel in my camper with a battery charge indicator that has the following information in the owner"s manual:
When pushing the “BATT” switch, the highest LED light illuminated indicates the estimated auxiliary battery condition. C = charge at 12.7 volts, G = good at 12.1 volts, F = fair at 11.6 volts, L = low at 6.0 volts.
Yet in the same manual it also says: "A fully charged auxiliary battery will read 12.7 volts DC and 1.265 specific gravity at 80°F (32°C). The auxiliary battery is considered discharged at 11.8 volts, and dead at 11.65 volts. When voltage drops below those levels, permanent damage may occur."
How can 11.6 volts be considered "fair" and 11.65 volts be considered "dead"?
As for permanent damage, I've also seen both dire warnings about running your battery below 50% (12v) as well as other reports that it is not a big deal - just try not to do it all the time.
I had a choice of two batteries at NAPA. One was a "dual purpose" (DP) battery, but I got the one that was supposedly the true "deep cycle" (DC) battery. Apparently the DP battery is a cross, giving both deep cycle capability and cold cranking capability (but neither as good as a battery designed specifically for either of those two purposes).
I guess I don't understand the point of a "deep cycle" battery if it can't be *deeply* cycled. On the battery itself, it says "engineered to withstand the rigors of long, deep discharges and long slow recharges". I doubt I will be getting a generator to recharge the battery on a regular basis while camping, as we go camping to get away from that kind of noise. The real benefit of the camper for us is the comfort it offers us over a tent as we get older and especially the nice big dry space for us and the kids on all those bad-weather days in the AdiRAINdacks. Also, not having to leave the tent to use the bathroom in the middle of the night is really nice. But boy, I really love having that fridge.
I guess the best solution for us would be to just have a second battery on hand for longer trips. I am a little disappointed that the fridge draws (so much) battery power. The other propane fridges I've had experience with (two in no-electricity cabins, one in a circa 1980 camper) do not require any DC power source at all. It would be nice to have the option be able to run the fridge in a mode that uses no battery power - but retrofitting would be much more hassle than just having an extra battery on hand. Oh well.
At least I have learned that battery voltage drop is NOT linear and that the real usable voltage is only above about 11.6. I will get that DC ammeter and see if I can't measure the current draw of those things that are always on: the fridge (if in use) and the lp sensor.
BTW: I do have a nice solar panel, but unfortunately our fav camping spots are pretty shady. While not on trips (and not in winter storage), the camper lives down in our meadow. No electricity down there either, but lots of sun, so the solar panel should be able to keep the battery topped off.
Thanks again all.
-J
There is one thing that is still bothering me though and that is the conflicting information I have seen about deep cycle batteries. First off, there is a monitor panel in my camper with a battery charge indicator that has the following information in the owner"s manual:
When pushing the “BATT” switch, the highest LED light illuminated indicates the estimated auxiliary battery condition. C = charge at 12.7 volts, G = good at 12.1 volts, F = fair at 11.6 volts, L = low at 6.0 volts.
Yet in the same manual it also says: "A fully charged auxiliary battery will read 12.7 volts DC and 1.265 specific gravity at 80°F (32°C). The auxiliary battery is considered discharged at 11.8 volts, and dead at 11.65 volts. When voltage drops below those levels, permanent damage may occur."
How can 11.6 volts be considered "fair" and 11.65 volts be considered "dead"?
As for permanent damage, I've also seen both dire warnings about running your battery below 50% (12v) as well as other reports that it is not a big deal - just try not to do it all the time.
I had a choice of two batteries at NAPA. One was a "dual purpose" (DP) battery, but I got the one that was supposedly the true "deep cycle" (DC) battery. Apparently the DP battery is a cross, giving both deep cycle capability and cold cranking capability (but neither as good as a battery designed specifically for either of those two purposes).
I guess I don't understand the point of a "deep cycle" battery if it can't be *deeply* cycled. On the battery itself, it says "engineered to withstand the rigors of long, deep discharges and long slow recharges". I doubt I will be getting a generator to recharge the battery on a regular basis while camping, as we go camping to get away from that kind of noise. The real benefit of the camper for us is the comfort it offers us over a tent as we get older and especially the nice big dry space for us and the kids on all those bad-weather days in the AdiRAINdacks. Also, not having to leave the tent to use the bathroom in the middle of the night is really nice. But boy, I really love having that fridge.
I guess the best solution for us would be to just have a second battery on hand for longer trips. I am a little disappointed that the fridge draws (so much) battery power. The other propane fridges I've had experience with (two in no-electricity cabins, one in a circa 1980 camper) do not require any DC power source at all. It would be nice to have the option be able to run the fridge in a mode that uses no battery power - but retrofitting would be much more hassle than just having an extra battery on hand. Oh well.
At least I have learned that battery voltage drop is NOT linear and that the real usable voltage is only above about 11.6. I will get that DC ammeter and see if I can't measure the current draw of those things that are always on: the fridge (if in use) and the lp sensor.
BTW: I do have a nice solar panel, but unfortunately our fav camping spots are pretty shady. While not on trips (and not in winter storage), the camper lives down in our meadow. No electricity down there either, but lots of sun, so the solar panel should be able to keep the battery topped off.
Thanks again all.
-J
