How to power a cpap

[nifty-stuff.com]

I bought the Bluetti AC200max and it has been great. It has AC, DC, and 30 amp output . I’ve had the CPAP machine plugged into it the past few nights

Thanks for the quick reply!

Have you used it as a kind of 24/7 passthrough / UPS for your CPAP... meaning that you can leave it plugged-in and charging 24/7, while keeping the AC and/or DC on all the time? From what I understand, the Bluetti's will power-off if no current is being consumed after a certain amount of time, no?

I'd really love a solution that keeps the battery topped-off all the time, and can allow the CPAP to run without having to turn on the output on the power station each night.

 

[Philfr]

Thanks for the quick reply!

Have you used it as a kind of 24/7 passthrough / UPS for your CPAP... meaning that you can leave it plugged-in and charging 24/7, while keeping the AC and/or DC on all the time? From what I understand, the Bluetti's will power-off if no current is being consumed after a certain amount of time, no?

I'd really love a solution that keeps the battery topped-off all the time, and can allow the CPAP to run without having to turn on the output on the power station each nigh

Thanks for the quick reply!

Have you used it as a kind of 24/7 passthrough / UPS for your CPAP... meaning that you can leave it plugged-in and charging 24/7, while keeping the AC and/or DC on all the time? From what I understand, the Bluetti's will power-off if no current is being consumed after a certain amount of time, no?

I'd really love a solution that keeps the battery topped-off all the time, and can allow the CPAP to run without having to turn on the output on the power station each night.

I’ve never used the pass through capability but I understand that it supports pass through charging so yes you could run it 24/7. I also understand that you should cycle it enough for healthy battery life. However they have two versions of their charger- with fan and without- so you’d want to be sure to get the non fan version because the fan version is very noisy. Bluetti forum -

BLUETTI Community

A place for all BLUETTI users Share, Chat, and Get Inspiration.

community.bluettipower.com

you can probably find other information there in addition to their website.

 

[MrNatural22]

My small 55ah lifepo in a Minkota battery box system is lightweight and connected to a 100w solar panel with a pwm controller will keep it topped of every day. I can get 4 days use without a charge if needed.
Inverters are bulky and are very inefficient to use and most cpap/bpap machines are able and will run better using dc.
dc adapters are available for most machines on Amazon or ebay.
Search for your model.

 

[Delmar]

1. He wants it to basically act like a UPS where he's got it plugged in all the time, and if power goes off, it will still be functioning just fine (from what I understand, most power systems / boxes will turn off if not pulling current, so he'd have to manually turn on the power box, no?)

First purchase a Kill-a-Watt to measure the actual CPAP power draw that will help you select the required equipment.

I installed a small used UPS to run my elderly moms TV and satellite dish during short-term grid down. Measured around a 100W draw. The backup system needed to be granny-proof autonomous so purchased an old APC SUA1000XL

The internal batteries are 18AH and the external Harbor Fright batteries are 35AH. Has around 1.3KWH of capacity that will easily run the 100W load for more than 8-hours (runtime graph).

Research the model of UPS to ensure it is pure sine, and accepts external batteries will extend the run. The APC "XL" with rear battery plug meets my requirements.

 

[nifty-stuff.com]

Hey All! I did a search for all threads with "cpap" in the subject line and read a handful of them... and this one was the longest and had the most details, so hopefully it's also the best place to post my question!

The SF Bay Area has had a lot of blackouts and my girlfriend's elderly Grandfather wants a battery backup for his ResMed AirSense 10 Elite CPAP machine.

From what I'm reading, there are a few things I'm contending with:

1. He wants it to basically act like a UPS where he's got it plugged in all the time, and if power goes off, it will still be functioning just fine (from what I understand, most power systems / boxes will turn off if not pulling current, so he'd have to manually turn on the power box, no?)
2. He'd like it to last 2-3 days with the humidity / heater on (if I'm reading the threads correctly, this uses about 200Wh per night)
3. This unit uses 24v (I could use a 12v DC to 24v DC voltage converter... but I think the plug is weird... see my next point)
4. It has a proprietary plug (I think there are some on Amazon that plug into cigarette lighter adapters and also do the 12v to 24v conversion)

Again, this isn't for camping, and ideally he could always just have it plugged in and working off the battery... with some kind of always-on pass-through charging from a wall adapter to the battery, then the battery to DC 24 volts (either using a cheap 24v up-converter or one off amazon)... but I'm not sure if this is the way to go?

So, what would you do? Would one of the "solar generators" like the Ecoflow, Bluetti, etc. work, or are they not designed to be on 24/7 and only pushing power 8 hours a night?

THANK YOU!!!

I think I need to go the most simple / reliable route for the situation above...

Is there a power station that:

1. Stays on 24/7 so the CPAP can just be plugged into it as though it was plugged into a regular outlet? (I know AC to DC is inefficient, but doing it this way won't require any other special instructions or components for elderly grandparents)?
2. Can always be plugged-in and charging / topped-off?
3. I don't think it needs to act as a UPS and/or "pass-through" device, but I'm sure that would be nice too.
4. Ideally is LifePo4 battery chemistry
5. Is around 500 - 1,000 Wh... which should be plenty for 2+ nights.

I think a unit like that would be perfect for them... if it exists.

... or am I just describing a regular ol' computer UPS? I think the issue is that a UPS isn't designed to run for multiple days, regardless of the load, correct?

 

[nifty-stuff.com]

Ok, after sitting with this a while, here's where I'm wondering if this can be DEAD SIMPLE with these components / setup:

1. Cheap AC wall adapter set at a voltage that keeps the battery (LFP, Lead-Acid, whatever) at a safe "topped-off" level. For example, maybe somewhere between 13.6 - 14.3v for LIFEPO4? I figure even a 2-AMP charger running 24/7 would be enough to keep a CPAP battery full for 8 hours usage per night.
2. Battery - SLA, LFP, whatever
3. CPAP DC Converter- Gpa's Resmed Airsense needs 24 volts. This adapter can safely take anything from DC: 12V-24V (9–32V DC MAX) and put out the needed 24V DC: https://www.amazon.com/KFD-Airsense-AirCurve-Machines-Replacement/dp/B07P6H994Q/

... and that's it, no?

Basically this SUPER simple setup should give Gpa 3+ nights of full CPAP "UPS":



What am I missing here? Any reasons this wouldn't work / isn't a simple good idea?

 

[SunFarmer]

I recommend a small UPS meant for home PCs or small business. CPAP machines draw very little power and I bet a small UPS would last a whole night.

 

[nifty-stuff.com]

I recommend a small UPS meant for home PCs or small business. CPAP machines draw very little power and I bet a small UPS would last a whole night.

I would, but:

1) None (under $500) are LFP that I can find.
2) He'd like it to run for 3 days, and I don't see any UPS systems (under $500) created for multi-day power
3) AC inverter losses are pretty big

 

[time2roll]

Is the CPAP enough? What about the fridge and a couple lights?

 

[nifty-stuff.com]

Is the CPAP enough? What about the fridge and a couple lights?

Great question!

The request was made for me to help them find a solution for the CPAP. I haven't heard of issues with the other items (yet).

So, for now, I'm just focusing on the CPAP

 

[Bob B]

Great question!

The request was made for me to help them find a solution for the CPAP. I haven't heard of issues with the other items (yet).

So, for now, I'm just focusing on the CPAP

It's always a good idea to include the possibility of future expansion.

 

[Delmar]

What am I missing here? Any reasons this wouldn't work / isn't a simple good idea?

Pinnacle of KISS. I use a trash-picked Belkin UPS for charging a single Harbor Fright battery and powering my Surface tablet car charger, fan, lights, USB ports, etc. Charges at 3A. Easy to find used cheap units on eBay. Although you might not require, it also has a 12V regulated output I use to power my sensitive wireless router and fiber modem.

My only concern...will the 24V converter standup to the extended usage. I would normally power from the grid, and plug in the 24V converter during grid down. Not totally autonomous.

 

[nifty-stuff.com]

My only concern...will the 24V converter standup to the extended usage.

Do you mean the one I linked / pictured above?

I have to imagine / hope it's made for 24/7/365 use... but I guess no way to really know for sure?

 

[time2roll]

Consider a small 700 watt Tripp-Lite inverter-charger (amazon $315 APS700HF) and an SOK 100ah or 206ah battery.
Connect the 12v battery then plug and play.

 

[Delmar]

Do you mean the one I linked / pictured above?

I have to imagine / hope it's made for 24/7/365 use... but I guess no way to really know for sure?

Buy one and try it, at least for the short term. Monitor to see how hot it gets. Then you will know for sure.

Otherwise you could purchase a quality boost converter with regulated 24V output. I would sleep better with this setup.

 

[nifty-stuff.com]

Consider a small 700 watt Tripp-Lite inverter-charger (amazon $315 APS700HF) and an SOK 100ah or 206ah battery.

Interesting, I've never seen them before. That approach definitely seems more expensive. What features / options is that inverter-charger providing that is better (for my use-case) than what I mentioned here? https://diysolarforum.com/threads/how-to-power-a-cpap.15679/post-684331

Buy one and try it, at least for the short term. Monitor to see how hot it gets. Then you will know for sure.

Ya, I'll probably give it a try

Otherwise you could purchase a quality boost converter with regulated 24V output. I would sleep better with this setup.

I would love to do that, but they have trigger resisters, loads, etc. etc. etc. etc. built into the unit that makes a simple boost-converter not work without a lot of fiddling. So, I'm hoping a simple $30 adapter will function just fine. Fortunately, they have a lot of great reviews, so I'm optimistic!

So, overall, no huge red-flags with the simple system I laid-out above?

 

[nifty-stuff.com]

FYI: I emailed EcoFlow about potentially using either the RIVER 2 Max or the River Pro for Gpa's CPAP. Mostly asking about leaving it on and plugged-in 24/7.

Basically they said:

"If the station is used as an EPS for a long period, please ensure that the station is always updated to the latest firmware, and when using the power station as an EPS for over a month non-stop, we recommend giving the power station a rest for a couple of days and discharge it then charge it again.

If you connect your CPAP machine to the DC output, there is a risk of automatic disconnection at low power consumption. If you want to use it, you can connect it to the AC output port. However, for safety concern, we do not recommend that you use our Power Station to charge your CPAP Machine. Because some of the unpredictable risks cannot be guaranteed. For the medical equipment, it is recommended you search for a more professional device for it."

I was really close to just picking one of these units up and calling it a day... but now I'm even more inspired to go with my "dead simple DC only" system mentioned above.

... I'm just waiting for more peeps on this forum to tell me all the reasons why it's a good and/or bad idea!

 

[time2roll]

Interesting, I've never seen them before. That approach definitely seems more expensive. What features / options is that inverter-charger providing that is better (for my use-case) than what I mentioned here? https://diysolarforum.com/threads/how-to-power-a-cpap.15679/post-684331

Option to charge or run small items when morning comes with no power.