Forum Discussion
- 12v machine still needs 12v power and probably entail pulling wire through unknown areas. I recommend wiring in a small inverter and use the existing outlet next to the sleeping area. If you can wire it in near the main electric panel there would be no wire to pull. Just make connections.
- LongOverDueExplorerThanks! I need a new one anyway, I will have to look into that!
- JimK-NYExplorer IIFor RV use, a 12 volt CPAP is essential. Unfortunately many of the providers just don't seem to understand what that means. My wife and I both got new CPAPs and had to exchange them. The tech came to set them up but they where 120 volt machines. Most manufacturers make identical looking and performing models which use 12 volts instead of 120.
The standard 120 volt machines are power hogs. In addition to run one from a battery you need an inverter. Inverters waste a lot of power. The best are about 90 percent efficient but most are a lot worse. A standard 12 volt CPAP will pull about 3 amps or a bit more and uses about 30 amp hours per night which is the majority of the useable power from most RV batteries. The humidifier usage is additional and can be greater than what the CPAP itself uses. My wife sets her unit on a hot water bottle to avoid needing the humidifier. - atwowheelguyExplorer
LongOverDue wrote:
Thanks everyone. I need an outlet for a medical device when I sleep. I had hoped for the best. I greatly appreciate your help!
Simplest solution is to get a 12V powered machine. (Edit: Apparently some DC powered machines won't run the humidifier, so that may not work.) Otherwise, there are some answers here: https://www.guaranty.com/blog/what-size-inverter-do-i-need-to-run-my-cpap-1 - LongOverDueExplorerThanks everyone. I need an outlet for a medical device when I sleep. I had hoped for the best. I greatly appreciate your help!
- atwowheelguyExplorer
DryCreek wrote:
If you want to bypass all of the techie talk:
You can use your propane stove to heat water and use a pourover to make really good coffee.
Another good tip? LED lighting. It makes the best use of limited battery capacity. That way if it's still dark when you get up to make your coffee, you can see to light the burner.
You can even combine both sides of the argument here. Buy a generator with a battery starting system. Get a solar charger to keep the generator starting battery topped off.
Last choice would be to do things the way I used to when boondocking: sleep when it's dark, and explore when its not. I am too old and crotchety these days, so I usually Wallydock for an overnighter any more.
^^ Good suggestions there. When I discovered that one 12V battery wouldn't carry a couple of incandescent lights for a few hours and then the furnace fan all night, I added a second 12V battery and replaced the lights with LEDs. - DryCreekExplorerIf you want to bypass all of the techie talk:
You can use your propane stove to heat water and use a pourover to make really good coffee.
Another good tip? LED lighting. It makes the best use of limited battery capacity. That way if it's still dark when you get up to make your coffee, you can see to light the burner.
You can even combine both sides of the argument here. Buy a generator with a battery starting system. Get a solar charger to keep the generator starting battery topped off.
Last choice would be to do things the way I used to when boondocking: sleep when it's dark, and explore when its not. I am too old and crotchety these days, so I usually Wallydock for an overnighter any more. - atwowheelguyExplorer
pianotuna wrote:
Hi,
They weigh 41.9 lbs each.
My daily cost for purchase of generator(s) has been $2.45 per day since 2009. The daily cost for solar is $0.66 per day since 2009. I actually bought them in 2005 which means cost has been $0.39 per day.
Cost to keep the solar running $0
Cost to keep the generator running 451 liters of fuel @ 0.979 per liter = $441.53 plus oil changes plus motor tune up.atwowheelguy wrote:
64" x 39" x 130 lbs. x 7 panels = 121 sq. ft. and 910 lbs.
2000 watt generator = 1.6 sq. ft. and 46 lbs.
Looks like I'm running a generator.
Sorry I got the weight wrong. The web site says 130 pounds on one tab and 41.9 pounds on the other tab. Unnecessary confusion there. My camper has 174 sq. ft. of roof area, much of which is occupied by an air conditioner, two vent fan ports, refrigerator vent, sky light, plumbing vents and antennas, all at the most inconvenient places. No way could I occupy 70% of that entire roof space with solar panels even at 293 pounds. Point is that sometimes the all-solar-power solution is just not practical for some.
If I were a penny counter, I would never have purchased a camper to tow around the country at 10 mpg. Hotels are cheaper. The pennies are not the end game. Yes, a silent campsite all the time would be great. I just can't see how it would be feasible for everyone. - pianotunaNomad IIIHi Phil,
My understanding is that for each cell (or string) that drops out and is bypassed the voltage will drop.
My system is nominally 33 volts, so I get some charging early in the day and some past actual sunset.
That is one reason it has been so hard for me to make the decision to replace what I have. It works extremely well and does exactly what I planned it to do. Just not enough wattage for full time.pnichols wrote:
It "seems like", for instance, that a bunch of 24 volt panels in parallel always putting out 24 volts - even with some panels being shaded - into the controller would be a superior arrangement. :h - pianotunaNomad IIIHi,
They weigh 41.9 lbs each.
My daily cost for purchase of generator(s) has been $2.45 per day since 2009. The daily cost for solar is $0.66 per day since 2009. I actually bought them in 2005 which means cost has been $0.39 per day.
Cost to keep the solar running $0
Cost to keep the generator running 451 liters of fuel @ 0.979 per liter = $441.53 plus oil changes plus motor tune up.atwowheelguy wrote:
64" x 39" x 130 lbs. x 7 panels = 121 sq. ft. and 910 lbs.
2000 watt generator = 1.6 sq. ft. and 46 lbs.
Looks like I'm running a generator.
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