UPS question: does the Airsense 10 require true sine wave power?

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jas32
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Re: UPS question: does the Airsense 10 require true sine wave power?

Post by jas32 » Sun Aug 14, 2022 5:42 pm

southerndoc wrote:
Fri Aug 12, 2022 11:47 am

…..If CPAP machines required sine wave power output, the innumerable users that don't use a sine wave UPS would have already posted about their CPAPs prematurely wearing out or malfunctioning.

Very few electronic devices "require" sine wave output.
Unless you lose power very often, how much time does your CPAP actually run on the battery of the UPS? I’m wondering if this is the reason why we don’t hear premature failures due to UPS use? Or maybe it doesn’t really matter.
This document from ResMed specifically requires using pure sine wave on their machines (page 5 under the paragraph “Using an Inverter”). Of course it could just be a CYA strategy on ResMed’s part.

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Dog Slobber
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Re: UPS question: does the Airsense 10 require true sine wave power?

Post by Dog Slobber » Mon Aug 15, 2022 2:01 pm

jas32 wrote:
Sun Aug 14, 2022 5:23 pm
This document from ResMed specifically requires using pure sine wave on their machines (page 5 under the paragraph “Using an Inverter”). Of course it could just be a CYA strategy on ResMed’s part.
That document doesn't "specifically requires using pure sine wave on their machines", it recommends them and only on certain devices, and typically only when using them with a humidifier.

The devices that are specifically recommended for pure sine wave are all pre-S9.

Regarding the need for pure sine:
  • Using CPAP with inverters is *very* common, the majority of inverters are modified sine. Nobody's reporting damage to CPAPs it's just not happening.
  • The majority of CPAP convert AC to DC with a brick in front of the device. Any damage would occur there on the AC-DC power brick.
  • The devices listed in the ResMed guide (incompatible with modified sine) are likely older devices that used AC.

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turbo
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Re: UPS question: does the Airsense 10 require true sine wave power?

Post by turbo » Fri Aug 19, 2022 5:06 pm

jas32 wrote:
Sun Aug 14, 2022 5:23 pm
turbo wrote:
Fri Aug 12, 2022 3:56 pm
As I mentioned earlier. I've been using modified sine with AS10 for a few years now with no issues. I'd post what battery I'm using, but I don't want to spam the board.
Do you mean your CPAP machine is running 100% of the time on the modified sine wave battery power, on extended camping/off the grid trips, or only when normal AC power goes out at home?
I keep the battery in-line as backup power at home %100 of the time, and also use it when off the grid.
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