Reported mask pressure ‘capped’ to 15.88 cmH20 by OSCAR? – Page 3

Wed Apr 07, 2021 2:31 am

“the pressure at the [machine] is NOT equal to the pressure in the mask”

Wed Apr 07, 2021 2:31 am

OK, if we were being pedantic about it you could state it that way, however my assertion was indeed correct. By increasing flow, it is of course increasing pressure to compensate for the drop in pressure caused by the leak. A PAP unit is just a ‘fan in a box’.. not exactly rocket science.

You don’t understand the system, or the incredible amount of math and computation that goes into making that “fan in a box” spin at just the *exact* right speed to correctly generate a desired pressure at the end of a circuit, taking into the resistances that are added by all the things that are dropped into that circuit between the ‘fan in a box’ and your face.

Increasing flow to compensate for increased leak does *NOT* increase pressure. you can put your manometer on the end of the circuit and vary the amount of leak, the pressure will stay the same, as the blower is ramped up and down to compensate for the varying leak by increasing and decreasing the air flow.

People have this *WRONG*, many people think that the machines increase pressure because of leaks, they *DO NOT* increase pressure, in fact, modern auto machines will in fact decrease the commanded pressure in the event of severe leaks, in an attempt to get the mask to seal again.

You can say it’s being ‘pedantic’ all you want, but what you said is simply wrong.

Wed Apr 07, 2021 2:31 am

Mask pressure is of course the only figure that truly matters – whether it’s close to the target pressure or not. It doesn’t matter what’s ‘reported’, the actual delivered pressure is based on measurement within a closed circuit. Anyway, as we’re talking about a 14cm difference that’s a different story…

Accounts to put on the foe list: mper!?, DreamDiver, Geer1, almostadoctor, ajack, stom, mogy, D.H., They’re often post misleading, timewasting stuff.

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