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CPAP question

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vthompson9100

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Will love your videos...soooooo helpful! And greatly appreciated. I have an off the wall question. I want to run a CPAP machine. There are two different volt and amp ratings, one on the device and a different one on the charging cord. Not sure which to use for determining size needs.....and it needs a pure sign inverter so not sure if that poses any issues or concerns?
 

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What are the volt and amp ratings on the power adapter and the Cpap Machine itself
 
Lol I clicked on this because my brain went CRAP question? I was thinking can't be that bad of a question.
 
vthompson9100 said:
Will love your videos...soooooo helpful! And greatly appreciated. I have an off the wall question. I want to run a CPAP machine. There are two different volt and amp ratings, one on the device and a different one on the charging cord. Not sure which to use for determining size needs.....and it needs a pure sign inverter so not sure if that poses any issues or concerns?
Click to expand...
 

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Your cord is rated for 7 amps the converter takes 120 volt ac between 1 to 1.5 amps and turns I into 24 volts at 3.75 amps the same as your Cpap is rated for. Theoretically you could make a cord that would allow it to run directly off of a 24 volt solar system. You cans probably purchase a 12 to 24 volt converter that will allow you to avoid most of the energy losses that occur from converting and inverting. Someone else should be more experienced with these type of converters than I am also if Cpap has any trouble running directly from 24 volt batteries.
 
24V at 3.75A is around 90W so lets say 100Wh per hour of operation (in reality it will be rather less, but best to over-estimate).

I agree with the comment above, a 12V-24V boost converter rated at >150W should run the beast off a 12V battery pack and avoid all the losses associated with an inverter, look at AliExpress. Many CPAP machines have a vehicle adaptor available, they are not the cheapest option but would avoid any issues with warranty.

EDIT https://www.amazon.com/TAIFU-Vehicle-Airsense-AirCurve-Machines/dp/B07VV231SJ

100Wh at 12V is around 9Ah, say 20Ah of lead-acid per hour of operation required (half that if you go lithium).

For the solar a lot depends upon where you are, have a look at a solar calculator for your location.

As an example, here in sunny Thailand a 300W panel will generate about 1,000Wh in an average day of operation. So in our area 1 x 300W panel would give you 10 hours of CPAP, that would need about 200Ah of 12V lead-acid. I'd double those numbers to cover the less than bright days and give you some energy for LED lighting.
 
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