Broken CPAP - Internal parts

As for Craiglist, check everywhere, not just your local. People will box it up and mail it!! There's a lot more machines in retirement areas like Arizona, South Texas and Florida.

I copied the data on the day it was having problem. Can anyone suggest what problem is on the machine or how do I find out? The data can be seen here: https://www.dropbox.com/s/32hbeutp5k8dpl8/cpap-data.zip. In the data you will see files with date 1/1/2098. This is because I pull the internal battery out, and looks like it reset the time. Anybody knows how to adjust the time on this machine?

The board seems fine, no loose soldering. I'm still thinking it might be the pressure sensor that is bad, but I don't know how to test this either.

Hi cpaman,

Your guess about the flow sensor would be right if my decoding of your .004 files is accurate.
30 MOTOR SPINUP FLUX HIGH (just showed up the first time)
84* FLOW SENSOR STOP
85 FLOW SENSOR OCCLUDED
25 MOTOR THERMISTOR OPEN
93 RTC VALUE

The reason why I marked "84" is because it shows up again and again (in 11 of the files, multiple times). The Motor spinup showed up in the first file only, but multiple times. The Motor Thermistor in three files, a single time each.

--SleepyCPAP

Thank you very much for looking into the error code. what did you use to look-up the error code? and how I can get one?
I worked with few electronics in the past, and usually things with sensors would give a lot of problems. That's why I was guessing that it would be the sensor. My guess the sensor is having problem probably because a while back, I put the CPAP machine near the ultrasonic humidifier, and looks like all the hard water vapor got into the sensor (it's super dry here in Arizona). So guys/gals, don't put humidifier near your CPAP.

I'm curious if anyone knows how to set the date/time on this machine, I shouldn't have taken the battery out of this thing. Also where would I get the pressure sensor for this unit?

My picture on the last posting didn't show up, it's the back side of the electronic board, with the pressure sensor on the top right of picture; 2 black box with snout on them. Here is the picture again.

cpaman wrote: I'm curious if anyone knows how to set the date/time on this machine, I shouldn't have taken the battery out of this thing.

It has to be done at the factory level or by someone like acbio repair shop.
The clock is set to GMT time at the factory and when you removed the battery it lost the preset time Special software is needed and we have never been able to find it or the special cables needed to get it done if we could find the software.

Hi cpaman,

I didn't use anything special to look at your codes. Just used a hex reader to open your .004 files, and then converted to decimal byte 16 (and each 9th byte after if the file continued to record more errors) and looked it up on the list. Here is the part of the old thread about the e-folder and .004 file error codes where I had figured that out:

viewtopic.php?f=1&t=91178&p=843803#p843721

--SleepyCPAP

Pugsy wrote:

cpaman wrote: I'm curious if anyone knows how to set the date/time on this machine, I shouldn't have taken the battery out of this thing.

It has to be done at the factory level or by someone like acbio repair shop.
The clock is set to GMT time at the factory and when you removed the battery it lost the preset time Special software is needed and we have never been able to find it or the special cables needed to get it done if we could find the software.

Right, the aforementioned "Service Center Tools Software". Seemingly the cause of the 94 RTC ("Real Time Clock") error (although factory recommendation is Replace PCA for that code).

Consequently, it might be a good idea to get the Error Code Log reset to see if the RTC code stays clear, otherwise changing out the Pressure Sensors may be futile)(OTOH, I guess the machine really doesn't care what time it is to blow air).

Thank for for the information and how to read the error code on this device.

Your are correct. The CPAP machine can operate fine even the date/time is not set, but the data would have a wrong date/time stamp on it. Currently I got the CPAP running again, don't know how long this will last.

I would like to change out the pressure sensor on this device. If anyone has a unit that I can use for parts, please let me know.

I also peeled the square white sticker label on the chip, this is what the chip name says:
(the first character on line 3,4,5 was hard to read, I think I got it right):
ARM H
STR911 FA
W44X6
HPAFC VG
KOR AK 101

And I found this document (http://www.datasheetarchive.com/dl/Data ... 243287.pdf) that this has USB, ethernet (network) interface, and date time function also. From the last picture I posted, on the right side of the board there is connector with 4 copper connection (this is like USB interface, 2 for data and 2 for power). It's under the SD card slot. So my guess this is for interfacing the CPAP with the USB cable on the computer.

This may not be the forum to discuss about the internal of the CPAP device. let me know if you know better forum to discuss this.

Thank you.

no response

cpaman wrote:From the last picture I posted, on the right side of the board there is connector with 4 copper connection (this is like USB interface, 2 for data and 2 for power). It's under the SD card slot. So my guess this is for interfacing the CPAP with the USB cable on the computer.

Actually, that adapter goes to serial first:



so if you plan to just start slicing stuff together you might want to add in a serial to USB adapter (although admittedly, I have never tried to hot-wire the thing to USB).

cpaman wrote:This may not be the forum to discuss about the internal of the CPAP device.

Actually, talking about CPAP machines is kind of a pleasant departure from people P&Ming about their jobs, Vitamin D as a cure-all, the end of the planet due to ObamaCare, etc.

BTW, in that first picture, is that a carpet that you have the PCA on?

Sludge,
the first picture, the PCA was on top of the cpap cover, which is on top of carpet. Probably you are thinking about the static from the carpet.

The adapter you showed, is this just a straight connection from PCA board to serial, or is there electronic board inside? If this is just straight connection to serial port, I can just construct the connection my self using only wires. Do you know what the baud rate settings and other settings to set the connection on com port?

Thank you.

cpaman wrote:Sludge,
the first picture, the PCA was on top of the cpap cover, which is on top of carpet. Probably you are thinking about the static from the carpet.

Actually, I was thinking that you were at some point walking on the carpet, so yeah, that thing could easily gotten a hefty dose of ESD.

I don't know what's inside that thing. Seems pretty hefty, so must be something other than straight-thru wires.

cpaman wrote:The adapter you showed, is this just a straight connection from PCA board to serial, or is there electronic board inside? If this is just straight connection to serial port, I can just construct the connection my self using only wires.

Here ya go:

cpaman wrote:Do you know what the baud rate settings and other settings to set the connection on com port?

This question is not clear to me. The board is from National Instruments, whose software LabView is the middleware to get from SysOne to Service Center Tools. LabView is configurable to suck up data as fast as the target will allow. If you're going to DIY an interface, it seems to me that what you need to know are the communication specifications of SysOne, right?