THAT OUTPUT CAPACITOR IS NOT NECESSARY. In my first build, that output capacitor was intended to add a tiny bit of additional "smoothing" for the 24-VDC output of the boosting regulator. It turns out to be unnecessary, because the boosting regulator's internal capacitance (on the output) is more tha...

Have the buck converter arriving this weekend. If I get the chance to finish this installation within the next week I'll post results. My 1st attempt will be 1 buck converter set to 3.3 V and no resistor. We'll see how that pans out. Thanks. THAT has zero chance or working correctly - wait for the ...

I purchased a 10A, 240W dc-dc unit. From specs it should regulate to 24V even with varying input voltages from 11-14V. I am just about ready to click on a "buck converter" that'll give me 3.3 regulated (fixed) volts. I was going to mount all this on the roof of the underbelly near the battery area....

Hi, kdauto !! From 2 posts above: Resmed made things 'complicated' in their own Power Supply Unit ("PSU"), with both a resistor AND a Voltage Converter. I think that implies the test (within the unit) measures current or voltage drop across the "sense" circuit at more than one level of "inline" inte...

A user on another board suggested that a 47k between +24v and center pin is sufficient. Resmed made things 'complicated' in their own Power Supply Unit ("PSU"), with both a resistor AND a Voltage Converter. I think that implies the test (within the unit) measures current or voltage drop across the ...

TheSnoringMan, thanks for your posting of the 12V converter. I was thinking about playing with a converter design also. Could you do me a favor and measure the voltage drop across the 2.7K resistor when attach to the cpap? IIRC, the Resmed CPAP performs a quick "sweep" on the wire - verifying both ...

They are selling one for under $20 on Amazon. It's not the ResMed brand one, but it should work. It is no more likely to void your warranty than the homemade one. D, I don't see it in a quickie search - just the original Resmed for about $80, and a BiX clone for about $60. There are plenty of cheap...

I designed a dedicated power source for it using a $4 150W 24V boost converter that resides in the power shed. There has been talk of how this could be done, but no one seems to have actually done it with a Resmed Autosense.... Nice work! I also built a converter box, and mine has also been working...

The specs for the airsense/aircurve DC converter appear to be the same as the specs on the s9 DC converter. 90 watt DC converter DC input 12/24V .....13/6.5A DC output +12v .....3.75A A note for future readers of this Thread: It is correct that S9 and S10 can use the same power supply units (AC->DC...

This Thread is primarily about Resmed, supporting 24V and 3.3V output lines with an inline resistor on the 3V. Respironics is completely different, and much more simple.

In our house, we have both this machine and a "Resmed Airsense 10". Recent Resmed Power Supplies put a unique Voltage (+3.3.V) on the center pin, and they require a certain resistance value to be resent along that conductor. (A value of 2.7k Ohms represents a "90 Watt genuine Resmed Power Supply"). ...

I recently put together a Converter Unit for "11-15VDC to Resmed 24V + 3.3V", and it works great. It is massively overbuilt, including a 24V regulated output "Boost Converter"; a mini-board "Buck Converter" (for conversion back to 3.3V), a big electrolytic "Filter Capacitor" (similar to the one incl...

Mostly I did it for the challenge. I did a similar "HomeBuilt" for another machine in the past, and because I have a close friend with the exact same requirement: A Resmed A10, with a need for use in camping trips (with a Travel Trailer which is exactly like mine). Since we canp without plugins, it'...

This one is built and tested ; it seems to work great. However, it's not cheap, and it's quite big and ugly. If you love building electrical gadgets, then feel free to make a copy! But if you don't like playing with electronic parts - don't bother, just spend the $85 and get the genuine article. The...

Resmeds have a 3phase motor with variable frequency drive. That's how they can accomplish the 4hz FOT pressure fluctuation. (As I slap my forehead) of course, it has to be VFD. Good thing I used their connector cable, and added that beefy Filter Cap. Thanks again! BTW, I slightly hijacked the Threa...