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StevenG · 07-09-2009, 03:14 PM

We are planning our second trip in our new (to us) 1987 32' Excella. We're staying a week with electrical and water hookups in a state park, but to and from is another problem.

Will the a/c run off the batteries, and if so, for how long?
Also, I have severe sleep apnea, and need to run my CPAP all night long. Will the batteries do both?

Thanks!
Steven

purman · 07-09-2009, 03:18 PM

NO, you will need a 3000 watt generator to run the ac. The cpap I not sure about. You will need an inverter to change from 12 volt to 110. then you could try it out during the day and see how long it lasts.

wkerfoot · 07-09-2009, 03:20 PM

Steven,

Check with your CPAP supplier and obtain for a 12V DC adapter. That way you won't need an inverter.

Bill

StevenG · 07-09-2009, 03:23 PM

My electrical knowledge is not good. I'm assuming (and you know what assumptions do!

) that there is an inverter in the AS so one can plug an appliance into any outlet and it will work when "boondocking" i.e. using the batteries instead of being plugged in to a power source. Or am I wrong here?
Thanks,
Steven

bob34787 · 07-09-2009, 04:14 PM

first, no you cannot run ac from batteries. as far as running appliances, you can run as much as your inverter will let you. On my safari I can run lights and radio but not refrig or tv.

purman · 07-09-2009, 04:38 PM

Thats all I can run on mine. It will not invert it to the 110 plugs.

StevenG · 07-09-2009, 09:20 PM

hmmm I wonder if the owner's manual for the 1987 models will tell if it will run the outlets? or should I simply assume, as it won't on yours, it won't on mine. sigh... I guess if I decide to boondock, I'll need a generator for my cpap... blast... life was so much simpler before I went to the dr. last month.

but then again, maybe now it will be longer!

loudruff · 07-09-2009, 09:34 PM

I have a CPAP. Got the adapter so that it runs on 12v. I have run it 3-4 nights without a problem with the batteries. However, we were NOT running much else....no waterpump, only a few lights....boondocking in the driveway to give it a try.

Lou

Maryw164 · 07-10-2009, 12:39 AM

Regarding your CPAP: it is basically a fan. Look onyour literature that came with the CPAP and find out how many watts the unit requires. Then go to Walmart, Costco or like store and buy a 12v power inverter that will handle the wattage. We bought one at Walmart that our son uses in the car when traveling to power his PSP, laptop, etc.

Now the A/C can in no way ever be powered by your batteries.

Hope this helps.

Mary

brotherjethr · 07-10-2009, 08:01 AM

Another way to put it: Assume for a moment that you -could- run the AC from your batteries. How long would it last? Well, let's do some simple best-case math: The batteries have no more than 50 amp hour capacity, so 12 volts * 50 amps * 1 hour * 2 batteries = 1200 watt hours. My AC runs at < 15 amps, so let's say it takes 120 volts * 14 amps = 1680 watts. 1200 watt hours / 1680 watts = 0.71 hours, or 43 minutes. And that's assuming 100% efficiency, ignoring the effects of such high current drain on battery capacity & life, and killing your batteries by discharging to 0%. A more realistic number is half, or 20 minutes.

So in other words, it wouldn't be worth the trouble.

StevenG · 07-10-2009, 08:31 AM

Thanks all! You've been a great help, and I appreciate it.
Steven

tpi · 07-10-2009, 08:57 AM

If you had 10-20 RV batteries (or equivalent capacity), the air conditioner would be viable.

This weight limits mobile use almost to the point of non existence-at least for travel trailers.

It would be interesting off grid combined with adequate solar capacity-such as a remote private campsite.

Johann1956 · 08-18-2011, 07:09 PM

Fuel cells are available as an alternative to generators, search for RV fuel cells, they will run of propane and are smart enough to run when batteries need charging and they are compact and quiet. Protonex Technology Corporation - Recreation

crazeevw · 08-19-2011, 10:15 AM

Quote:

Originally Posted by Johann1956

Fuel cells are available as an alternative to generators, search for RV fuel cells, they will run of propane and are smart enough to run when batteries need charging and they are compact and quiet. Protonex Technology Corporation - Recreation

Johann, any idea what these Fuel Cells would cost?

xrvr · 08-19-2011, 12:08 PM

Inverters? converters? are we confused here? jim

SeeMore · 08-28-2011, 10:31 PM

You need to get the 12v cigar plug cable for your CPAP machine from the supplier. Although most people use their machines at home, the device actually uses about 9 to 10 volts of DC current natively which is converted by the supplied 110 cable when in home use. You don't need to convert your 12v supply to 110v and then back to 12v needlessly. You just waste energy in the process.

In your AS, running just the CPAP, you can usually get two or more nights of battery time from your battery bank after the normal late dinner and pre-sleep reading time light use. Your machine's wattage can be read off the label or supplied to you by the manufacturer; most are quite low.

My AS came with a 12v cigar plug outlet in the bedroom and beside the dinette.

**DKB_SATX** · 08-28-2011, 11:45 PM

Quote:

Originally Posted by dpe01

You need to get the 12v cigar plug cable for your CPAP machine from the supplier. Although most people use their machines at home, the device actually uses about 9 to 10 volts of DC current natively which is converted by the supplied 110 cable when in home use. You don't need to convert your 12v supply to 110v and then back to 12v needlessly. You just waste energy in the process.

In your AS, running just the CPAP, you can usually get two or more nights of battery time from your battery bank after the normal late dinner and pre-sleep reading time light use. Your machine's wattage can be read off the label or supplied to you by the manufacturer; most are quite low.

My AS came with a 12v cigar plug outlet in the bedroom and beside the dinette.

I think that depends on the CPAP machine, actually. Mine doesn't have an external "brick" power supply, the 120v cord connects directly to the pump section via a Sony-style symmetrical 2-conductor connector. Mine's a Resmed S8 Compact, and it says 100-240 VAC, 50-60 hz.

I'd be interested to learn what models have their power supply on an external brick and take DC in like my laptop, they'd be high on my list for the next one.

SeeMore · 08-29-2011, 11:42 PM

Check out CPAPSupplyUSA.com. The Aeiomed Everest is a nice small portable and has a battery pack to go with it when traveling to a place without overnight power. DirectHomeMedical.com has a variety of power connectors for CPAP and BiPAP machines.

In your case, a small inverter (under 150 watts) can be had pretty easily and will allow use via the cigar plug outlet.

**DKB_SATX** · 08-29-2011, 11:45 PM

Quote:

Originally Posted by dpe01

Check out CPAPSupplyUSA.com. The Aeiomed Everest is a nice small portable and has a battery pack to go with it when traveling to a place without overnight power. DirectHomeMedical.com has a variety of power connectors for CPAP and BiPAP machines.

In your case, a small inverter (under 150 watts) can be had pretty easily and will allow use via the cigar plug outlet.

AEIOMed seems to have ceased production after a factory fire.

It looks like it was a very nice product, I'll check out competitive items.