CPAPs in Hammock

[sloth99]

Thanks. Makes sense to stick with the manufacturer's cable.

[Cruiser51]

Just a bit further, I originally bought a 12V power bank for my Respironics, which takes 12 v ... with the recall I got a ResMed which takes 24 V, the ResMed cable takes the 12 v and converts it to the 24 v needed. So the 12v car adapter for your unit takes care of any adjustments needed to make your unit work.

[sloth99]

Just a bit further, I originally bought a 12V power bank for my Respironics, which takes 12 v ... with the recall I got a ResMed which takes 24 V, the ResMed cable takes the 12 v and converts it to the 24 v needed. So the 12v car adapter for your unit takes care of any adjustments needed to make your unit work.

Thank you. Do you know if the conversion from 12v to 24v uses extra Wh? My Pilot 24 is 95Wh, gives me 2 nights, so roughly 50Wh per night. Will a 266 Wh battery give me 5 or so nights at 50Wh per night, or are additional Wh consumed in the 12/24 conversion, meaning I'll use more Wh per night?

[Crazytown3]

sloth, I use an AirMini with that same Pilot24 battery. In this case, I *think* the conversion is probably done by something inside the battery case so it outputs 24v instead of 12v. If you can find a 24v battery with more Wh, you will get more nights of usage, but finding a reasonably priced higher Wh 24v battery is tough. At some point you would end up lugging around a big freakin battery. That's where the 12v batteries with the round 12v "car outlet" come in to play. You can use a 12v battery with higher Wh (which are easier to find), and use the ResMed 12v-24v adapter cable to power your AirMini; I think ResMed calls that adapter the DC/DC converter.

I see you are in BC. I have the AirMini DC/DC converter cable that I have never used. It just was too bulky and heavy for what I needed. If we could figure out the logistics of it, I would just send it to you if you want it.

[Cruiser51]

Thank you. Do you know if the conversion from 12v to 24v uses extra Wh? My Pilot 24 is 95Wh, gives me 2 nights, so roughly 50Wh per night. Will a 266 Wh battery give me 5 or so nights at 50Wh per night, or are additional Wh consumed in the 12/24 conversion, meaning I'll use more Wh per night?

I have found using the manufacturers cable doesn't give me any noticeable loss in total run time (I am upconverting 12 V to 24 V).

I can't directly answer your question, but I will give you the numbers from my system to demonstrate the process I use to arrive at number (which work out for me)

Battery: 266 wh/22.17 AH 12 Volt Lithium battery (FYI AH is just WH divided by voltage ... I like to work in AH, but you don't have to)
CPAP: ResMed S10 @ 6 cm, no Hum chamber or heater, no ramp either (it takes extra power)

I have a RC car battery load analyzer that I can use to measure the power draw ... the S10 runs at .35 AH (4.2 WH) ... so 22.17/.35 gives 63.3 hours of operation from a full battery (for WH that is 266 /4.2 for 63.3). this gives me at least 8 nights comfortably.
The Respironics units I had were drawing ~.25 AH under the same conditions, so would run that much longer. Given the recall and safety concerns, that manufacturer isn't really viable for the foreseeable future though

If I were using your battery, for my CPAP, I would get 95/4.2 = 22.6 hours of operation ... here I would likely drop my pressure to 5 and get 3 nights from the unit, I also believe there is a cable that allows connecting 2 of these batteries together, allowing use of all the power, instead of having partials leftover.

Points to think about:
- idle power usage is not insignificant, I measure mine at 30% or 1.6 WH .... so unplug when not in use
- power consumption is proportional to pressure setting , going from 6 to 8 will draw about ~25% more power
- the majority of the power is used on inhalation, the faster your sleeping breathing rate is, the more power you will use
- the reason I break it down to hours, sleep duration is personal and even then it varies with environment
- different units draw different power, generally the smaller travel units draw more power than the home units, so you save on size and lose on needing more power


Brian

[sloth99]

That's a super awesome offer Crazytown, thank you very much. I'll see if I can figure out how to pm you.

[sloth99]

Great information, thank you very much Brian.

[Slugger]

The battery I mentioned is in stock right now as of today: https://www.amazon.com/dp/B0791WDZTW...roduct_details

[sloth99]

The battery I mentioned is in stock right now as of today: https://www.amazon.com/dp/B0791WDZTW...roduct_details

Thanks very much, great tip! Sold out by the time I got there. I'll keep checking.

[Cruiser51]

Sloth ... that not available is likely because you are accessing from Canada, if you have a US zip code, I think it is still there.