[Equipment] Battery usage with CPAP (S7 and A10)

[MrGadget]

I have an older S7 Autoset II that I was considering using with 12v batteries when traveling/camping do to it's size and maybe dealing with power outages instead of my brand new A10, but I cannot find any references to determine if it also has the reversed polarity 5.5x2.5 mm plug/jack like the S8 does. I can build a physical cable that plugs into a 12V auto plug, and I've done some searching, but I cannot find information on the polarity of the DC jack on the S7, only the S8, and I have a feeling that the issues mentioned about the reversal of standard polarity on the S8 may be because it changed between those models, (and specifically because I don't want to let the magic smoke out ).

Does anyone know if this information is obtainable somewhere? RESMED's website has only newer product information, and I can't get any hits about the S7 on CPAP related forums. I do not have an original DC cord/adapter to check the polarity, I only have the simple AC cord with the "figure 8" IEC320C7 connector that goes into the S7 via the AC connection, and no way to tell the polarity of the DC jack without an adapter and cord that is so old it's not longer stocked anywhere.

I also am considering just using a Suaoki Portable Solar Generator (I can't post links yet) instead of cheaper batteries, and was wondering opinions on it as well. As then I would also have a battery back up option at home and when traveling, but the double power transforming would really be a waste if I could only plug in via it's AC connection and not use the DC power connection, not to mention the cost.

[trish6hundred]

Hi MrGadget,
WELCOME! to the forum.!
Hang in there for answers to your questions and much success to you as you continue your CPAP therapy.

[OMyMyOHellYes]

I don't know at what point in time or on which model they went over to the dark side. Let us know the results for reference if you find the answer to your question.

OMMOHY

[rem52]

An electronics technician could measure the output of your power supply and tell you which lead is pos and which is neg.
Look for a local electronics store or repair (repair, who repairs...) shop, or a local amateur radio operator.
Also look on the power supply, it should be marked with a symbol showing polarity like all good electronic power supplies...

[justMongo]

rem52: The AC power supply is internal to the S7.
There is a separate jack for use on 12 VDC. It's the polarity of that jack that the OP is asking for.
Without further info, one would likely have to open up the machine and trace the circuitry to determine polarity.

[MrGadget]

justMongo: Very correct. And thanks for all your other "battery" posts, I've read a lot of them.

rem32: You are also correct, but I am an old retired electronics technician, that's why I referenced the "magic" smoke. I appreciate you trying to help anyhow.

trish6hundred: thanks, I'm new here, but have been successfully using CPAP for over 7 years. It's sometimes challenging, but using it was life changing in a very good way.

But I finally dug out my old manuals and stuff, I have an S8, not an S7, so my first question has already been confirmed previously about the center pin polarity. So I either need to buy one of the aftermarket DC adapters for the s8 $100 on ebay (because there are no original DC-12's available at any CPAP store, they all show discontinued) or just make one of my own, but I don't have access to the power filter part, and that may be critical.

I'm really wondering if I can just build a straight 12 plug with reversed polarity and use this Suaoki Portable Solar Generator, (still can't post links yet, but google it, it's on Amazon) but I'm not sure if it will only provide 11v and if the Lithium batteries drop voltage as they run down, which would not work. Also if it can be charged up in a car while driving, because you can't use portable solar panels while moving. It looks really promising because of the smaller size/weight/portability. I've sent email to the mfr, but haven't gotten any responses yet.

I could just use an adapter like ones that are used for the A10 and a C100 portable battery and not try to use the S8. But I really don't want to subject my brand new A10 to the rigors of travel/camping, I would prefer to use the S8 that is my backup.

Any opinions on the Suaoki Portable Solar Generator?

[MrGadget]

I just realized even when I will be able to post links there is no commercial support, so for the ease of searching, I'm adding this Amazon info B018GE8JPY for the Suaoki Portable Generator, if any of the official suppliers have it, please let me know, as I would prefer to support local or companies that help.

[OMyMyOHellYes]

Should be able to just build a cord with outside pos, inside grnd. As a matter of fact, I got a powerpole assembly and out of an anal sense of something, was checking continuity when I got it. No continuity on EITHER lead. Just for snits and giggles I touche the opposite connector surface and noted that the outside was POS, inside NEG in spite of wire markings. I don't know how they effed that up. But I called and bitched and they sent me a new one and I got to kept the old one. A couple months later I actually acquired a new S-8 so I lucked out.

OMMOHY

[justMongo]

If it's an S8, be sure to read the plate on the bottom. My VPAP S, S8 requires 24 VDC. I think S8 CPAPs and Autos are 12 VDC; but don't hold me to that.

[OMyMyOHellYes]

If it says "Autoset II" on the top, it's an Autoset II. Same as my travel unit.

Why does your signature bug keep runnig in figure 8s?

OMMOHY