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No problem, questions are what it's all about...

Here is a good link for info on batteries. It is quite comprehensive.

viewtopic.php?t=28154

I have one battery and one charger, it's a 105ah, which is quite large. For a trip, I will only use it for the CPAP, because that is my No.1 priority, unless I have a guaranteed method of charging it - solar can be a bit too dependant on the weather. At home I'm using it to power a radio during blackouts, and luckily haven't had to use it to sleep with yet. (I did miss my only night on CPAP during a power outage before I bought the battery.) The plan is to hook it up to an inverter to power a couple of PCs for emergencies too, as it has plenty of capacity to handle that for a bit as well as CPAP for a night. The power goes off quite often (up to 3 times a day at work, luckily only about 3 times a week at home), but it doesn't stay off for days, so I just need it to drive the CPAP for one night.

It is setup very simply. My Resmed has a DC power connector on the back designed for their DC cable, but it works on 12V, and so I made a cable that connects it directly onto the battery (the polarity is important - it is opposite to the 'normal' polarity, and has the negative on the centre pin). I'm not sure of the best setup for other CPAPs, but as far as I understand (from reading other topics here) the Respironics DC cable is fairly cheap and easily available. Of course all the heated humidifiers run on AC, so you need an inverter to run them. I just left the humidifier at home when I went away - we were in the mist belt, so I reckoned a lack of humidity wouldn't be an issue.

I charge the battery about once a week, more if I have used it - it has a charge indicator built in, which makes it easier - I know I can get at least 1 night out of it even when it indicates it needs charging. Yes, I'd take it camping, along with a ton or two of other stuff!

It weighs about 27kg (60lbs), and cost me R1350 which is around $200 I suppose. I doubt the price here is meaningful for you over there though.

I'd really recommend reading through WNJ's post I linked to earlier - together with Bill's comments, it's really a great starting place.

Colin

Thanks Colin,

I guess it really is different in different parts of the world, country, or even within each state or county. So one size doesn't really fit ALL.

It just seems that I have read many posts here that say oh just need this or that - when there really is sooo much more to it. And it ALL needs to be done BEFORE the lights go out.

Where you and I may not have a problem lugging a 50-60 lb. battery or even connecting it, or trying to figure out how to charge it - others may not feel the same way. Others may be willing to pay a little more or even go without. For me - the tinkering keeps me busy.

I often try to find a way to make due with what I already have "ON Hand". Kinda like recycling? Enter the car jump starter - I didn't think one would be enuff either. So I bought another one on sale for $25 (usu. $30) w/o an inverter but who cares. If you want that YOU could always buy an inverter separately.

But hey thanks for the reality check.

For a second opinion - read this very well written and detailed post
Batteries for CPAP - How to select, use, charge, etc.

Thanks Again,
GumbyCT

WNJ wrote:Gumby,

You should do a reality check on the jump-starter idea.

Some may think these devices a good thing to keep in your car to jump start if your battery dies, but they are terribly ill-suited for extended use such as powering a heated humidifier when camping.

They will provide a lot of power for a very short time. They will not provide much power for very long.

What are the amp-hours of the battery? This is the true measure of capacity for batteries. You get 22 amp-hours with the Sears unit you linked to.

You can’t draw down a battery much more than 50% without dramatically shortening its life. Figure you have maybe 12 usable amp-hours.

Inverters are very inefficient. About half the power drawn from the battery is wasted as heat. Now you’re down to the equivalent of about 6 amp-hours.

Figure a very short night’s sleep with CPAP with heated humidifier before the battery is dead. How are you going to recharge? From your car? What is the recharge time for these units? Do you really want to run your car at fast idle for eight hours every day to recharge one of these?

Also, these batteries will not take many discharge-recharge cycles before they die. They’re designed for occasional use of a few seconds duration (starting a car.) They’re not designed for deep-cycle use.

For camping, get a deep-cycle battery and the proper DC adapter for your CPAP. Use the humidifier as a passover. Camping it will work far better than in the much dryer heated air in your home in wintertime.

Wayne

Best solution for the cold air problem with the passover humidifier I've found is put two of the 12 hour Body Warmer heat pads by the Grabber Co. (http://www.warmers .com) around the humidifier tank stuck to a piece of heavy duty foil then attatched with a rubber band and covered with a towel for insulation and then run the hose in the sleeping bag zipper low in your bag, then up through the bag. The water in your tank will rise to about 83 degrees. My water at home is usually around 100 degrees on the humidifier.Better than nothing. Get a Honda 1000 suitcase generator for car camping. 29 llbs. and super quiet.

being a skeptic and contrarian, I have serious doubts with the effectiveness of the warmer.

Simple phhysics limit the amt of heat released in the chemical reaction utilized in this product.
The temp generated is also probably not enough to provide continuous energy to provide a suffiecient amt of vapor.

The continuous blowing of air over the HH will rapidly dissipate whatever amt of energy generated.

There is simply not enough heat energy to provide enough to be effective.
I could be wrong, but very seriously doubt that this would be effective.
I could be wrong

tom

GumbyCT wrote:

WNJ wrote:Inverters are very inefficient.

Can't disagree there.

There is soo much more than to this short sited idea that yes eventually leads to using this device to charge a deep cycle marine battery.

So many on here recommend using a deep cycle battery and while I am sure some know how to even hook it up - no one has mentioned how to keep it charged. Or even how to connect it for those who aren't as technical as we are? But I will leave it there.

https://www.cpap.com/cpap-machine/CPAP. ... Cable.html

Use of an INVERTER with charger will recharge this battery....... I have used it and had two nights at 15cm without humidifier running.
BEING a CHEAP OLDFART ----- Did not like the price -BUT- Lugging a deep cycle battery around verses this 2 1/2 Lb. version is worth it.... I think you could get even more time out if you have a lower pressure?

Comes complete and has a great carrying case..... I used it on a BUS trip across country < Won't do it again!> but it worked!


BERT . . . . . . . . YES this is an ENDORSEMENT for CPAP.COM