Reliable Battery Power for CPAP machine

Something is most definitely wrong!!

I have just returned from a 3 week sojourn, and had no problems whatsoever.

I use a Res Med Auto Spirit, and it _Affordable_Storage_Drawers.aspx around 1.3 amps @ 12 volt running @ 9 bar.

I am assuming you are NOT using the humidifier? That will kill any battery system, as it requires pure sine to begin with. Humidifier is unnecessary whilst camping. There is usually enough residual humidity inside the tent / swag / camper to compensate.

I sometimes sleep for maybe 10 - 11 hours @ night, and I have never had a problem.

Mem mes me if you want to talk further.

Cheers

Wolfie

Are you running your machine from a 240V inverter or is it 12V direct? I use 12V direct to the CPAP, run 39ltr engel, HF radio and versa lights and seem to cope ok. May also need to look at the charging side....big cables all the way!!! Cheers

On a standard 50amp battery run a 40 ltr Engel, lights and Res Med Auto Spirit machine I will normally get 24hrs out the battery that is fitted to my Heaslip Tray on. I changed to a 100amp battery in the camper which allows for 48hrs base camping without having to reconnect the truck to the camper which has another 2 x 70amp batteries. I was suprised when I could only get 24hrs out of the smaller battery before the alarm of the inverter went off.

I'm off to the corner country early next month for two weeks so I will be interested to see how my gear stands up to the power draw.

Mac,

If it used to work OK and now doesn't, I'm guessing your aux batt is wellington booted, or the charging system. I'd get it looked over by a battery expert.

Try Chris at Battery World, Wantirna. Honest bloke, fair prices.

Cheers,

Jim.

Hi Nissan Gnome, Jimbo’s suggestion is the safe way to go but being in the situation that you are, it would also pay you to carry a multi meter with you so you can get an idea of what is happening around your vehicle.

The problem sound like you have a battery operating on it’s last legs but you may need to have your alternator overhauled, or maybe it’s simply a bad or loose connection somewhere and any number of other possibilities.

A multi meter will help track down the problem and may save you some money in the process.

Cheers.

Hi, I know I will start some arguements here, but are you using a deep cycle battery for your aux? If you are I would change to a starter for the Aux. The reason I say this is because you said it did work ok, but now it doesn't. The problem I have found is the (wet cell) deep cycle only accepts a charge slowly and will not get a full charge via driving all day. So leaving home your battery is full, but each day it doesn't quite charge to what it was the night before. By 3 weeks away and its not working much at all because it needs a long slow charge from a 240 volt supply. Starter batteries recharge quickly. I know you can get AGM batteries, but for the cost a good starter will do the job fine. My aux starter batteries last a bit over 4 years. If you connect everything through a low battery cut out switch you'll never have a problem with a starter as a second battery.
That is MHO and I know many will disagree, but I hope it helps

I also use a cpap running from a 300w sine wave invertor, and it _Affordable_Storage_Drawers.aspx just over 1 amp, and I dont use the humidifier, I find I can just get 2 nights camping in medium weather, with a 1000cca battery and the n70zz starter battery, with them linked.

I carry a bushranger 4000 also, and have had to get up a couple of nights on the 2nd night camping to connect it to the aux battery when i ran 2 x n70zz's before getting the bigger battery, and had no trouble since. The bushranger plugged into the aux acc plug then charges like a 3rd battery while driving, and disconnects when the acc are turned off.

I have also had to jump start the car with the bushranger 4000 a couple of times after 2 night camping, when the batteries have been joined as one.

My new truck wil have n70zz start battery, and 2 x n70zz's linked as one battery as the aux.

The cpap has been easy, after afew years ago, before my wifes kidney transplant, when we had a 1500w sine wave invertor and 5 n70zz batteries in the car to run the wifes dialysis machine for 10 hrs each night, and would then run the gennie in the morn with a battery charger to top them all up again before driving.

With 5 batteries, I would have to run the car for about 20 minutes when she started the machine, or the 5 batteries wouldnt last the full 10 hours without the voltage dropping low enough for the low volt alarm to go off.

Would definitely check out battery/charging system.
Tuther half needs a CPAP machine and the first one she had was a Fischer n Paykel unit (can't remember model) drawing around 180 watts on 240 volts so free camping posed some problems. (thats about 15 amps on 12 volts). Had to use a pure sine wave inverter. We did manage a day here and there but not as often as we would have liked!!

She now has a Puritan GoodKnight 420 (12v) CPAP, Devillbis passover humidifier and 12v heated tube.

http://www.cpapaustralia.com.au/shopping/puritan-bennett-420-goodknight-passover-cpap-humidifier-with-12v-heated-tube.html

This combo _Affordable_Storage_Drawers.aspx only 2 -3 amps. The puritan passover humidifier wasn't available at the time we purchased our gear hence the Devillbis.

With 2 x 80 amp batteries in the van running lights, CPAP, Vitrifrigo 12v fridge and car fridge we are now capable of spending several days away at a time.

BEWDY