Back up batteries

Hi, this is my first post. I have had sleep apnea for like 30 years, I use the Dreamstation BiPap mode, pressure is 12/6. I have a battery back up question and was wondering if anyone here has had any experience. I was going to purchase a marine deep cycle battery but then there were warnings about acid release, battery trickling and chances of serious occurrences, so I spent a fortune buying the Freedom battery.

So it states that you can get up to 16 hours on cpap with a pressure of 10, I'm wondering if a BiPap uses more power and if my settings will drastically cut the hours.

TIA

Hi hev67

I believe that Sierra has done some homework in this area so this is just a response to encourage you to come back.

In the meantime could I ask a few pertinent questions?

Do you use a humidifier?

Do you use a climate control hose?

Will you be using it in close proximity with your vehicle?

I have not seen good information on the DreamStation machines but here is a link to the ResMed advice on batteries. The big advantage of the DreamStation is that it uses 12 volts instead of the 24 volts that a ResMed uses. This means you need no inverter or DC to DC converter. Your pressures are relatively low and in the CPAP range. If you look at the table on page 7 on the right hand side for the Series 10 machines with an IPAP of 12 cm you get a range of current draws. With no humidifier (or turned off) and no heated hose, it only takes 1 amp for 12 cm pressure. And it increases significantly as you add humidification and heated hose to as much as 5 amps at 12 cm. Once you determine the amp draw you divide the amp-hour capacity of your batter by that amperage and you get the number of hours it should last.

My wife and I both use ResMed machines in our trailer. When we camp without AC power we turn off the humidifier and heated hose to minimize the current draw. We recently camped for 4 days without AC power, while one of our neighbours unfortunately ran his generator all night to power his CPAP! Our trailer has two 6 volt golf cart batteries, and I use a 70 watt solar panel to recharge them as much as possible each day.

Thanks for your replies. I have to admit, that info was a little confusing. I actually have all the cords I would need for using a Marine deep cycle battery, just never bought the battery because of the warning for storing it in the apt. To answer a few questions, I won't be using the humidifier or heated hose, and my car is parked right outside my door, I have the adapter for that too.