Battery Usage Time

5er wrote:Trying to find some simple way to power my Series 234 F&P cpap machine in my recreational vehicle. Apparently this cpap machine does not have a 12 volt input but the RV does have a 400 watt inverter. I assume that if I set the humidifier (heater) to zero the RV battery life would be greatly extended. The RV has two deep cycle 12 volt batteries on board and two batteries in the tow vehicle which are continuously connected to the RV unless physically disconnected. My question is: Is it a simple matter of plugging the cpap into the 400 watt inverter? Will the inverter provide enough power for the cpap and for how long? Is there a risk of doing damage to any of the component parts?
Any and all input welcomed
5er

Greetings 5er, as nanwilson noted you should be fine. The RV vehicle's inverter may be pure sine wave inverter, in which case the humidifier might work. You want to check with your RV manual to see if it is a pure sine wave or modified sine wave inverter. If it is a modified sine wave inverter, you normally need to turn off the heated humidifier. The exception to that rule is the S9 units, which can use modified sine wave input to drive the heated humidifier.

The amount of time you should get out of your setup depends on the xPAP unit you use. However, with two deep cycle batteries you can definitely get enough time to handle several nights. You will then want to recharge the batteries, but normally the arrangement is such that all you have to do is run the motor of the RV unit (or vehicle that tows the unit) for a while.

And of course, when in doubt call your RV vehicle manufacturer. I am more than willing to bet that they already have answered your question (over and over again). (Of course, you may be able to find the information online at their support website).

You should be in good shape. - Hope that helps.

Thanks all for the replies. Our RV lifestyle was getting a little tedious in that we would need to seek out an electrical hookup every night so that I could run the cpap in order to drive safely the following day. Our world has expanded!!
5er

Good post. Just the other night our power went off for 4 hours! It sure affirmed why I need the CPAP.

I have this battery:

http://www.batterymart.com/p-12v-35ah-s ... up-u1.html

It doesn't say on the website, but what I got was a Leoch LP12-35 sealed lead acid battery. It says it's a 35Ah battery, but I'm not sure how that translates to CPAP use hours. I figured it would probably be good for a few nights, though. The most I've used it without recharging was 16 hours (2 nights @ 8 hours per night) at a pressure range of 9 - 11.

This battery will not power the humidifier at all, the light just blinks and it doesn't heat up, so I leave it off when using the battery. I would like a more powerful battery that would run the humidifier, but since I rarely use it anyway I haven't got around to getting one. More powerful batteries are heavier and much more expensive, so this was very economical option for the rare times that I do need to use it. It's really worked out well, though. Since I've had it, there have been some nights I would not have got any sleep at all because there was a power outage.

Great topic and posts .. just the info im looking for. I too RV alot, and also own an Eliminator 800 watt Powerbox, like the one chatted about in the previous posts. When camping in non-electric sites, I recharge this powerbox on a daily basis using a 30 watt solar panel, which takes about 4hrs in full sunlight and 7hrs on a cloudy day. No need to fire up your RV to recharge, just plug and play.
I will be using this box to power my PAC later this year, and will post the info.

d-mo

nanwilson wrote:I have a 12 volt deep cycle marine battery bought new in May.
modified sine wave inverter, 300 bought new in May.
I do not use the humidifier
Pressure at 11
Have gone up to 3 nights at a time, about 8 hours per night.
I charged the battery when I got home with a marine battery charger.
I have used the battery 3 week ends so far.
Hope this helps with the poll.
Cheers
Norma

Hi Norma,
Could you please specify what is the make/model of your modified sine wave inverter? Can you plug your cpap machine directly into the inverter or is some type of cable required? Thanks!
Sincerely,
Karen