Data Card

I think my machine wipes and reformatts my data card every time I put it back in the machine! This means I wont be able to PROVE compliance when I go for my follow up.

btown wrote:I think my machine wipes and reformatts my data card every time I put it back in the machine! This means I wont be able to PROVE compliance when I go for my follow up.

You are allowed to think whatever you want in this Great Country- America.

What makes you think that it erases the card each time?
You know you can go into the SD card folders and look....I bet all your data files are there in the P0 folder.

Because the used space size on the card never changes significantly. It's always 600-700K when I plug the card in. This makes sense if the card is being wiped then reloaded with new data every night. Also when I put the card in the cpap it says new SD card detected and has a little elipsis that constantly cycles for 30-40 secs. (seems like its formatting the card)

The small amount of data for each night will not make any huge change in space available on the SD card.
I have a card that I used for 6 months and only 0.3 space was used up. Tiny amount of data on the SD card.
You have no worries there at all.

It is normal for the machine to do its "thing" when you insert the card. It is reading it and it will ADD any missing nights (like if you left SD card in computer..which I do fairly often). It is not erasing the card.
Data is stored on your computer..all except flow waves. You can put a brand new SD card in your computer and it will write ALL your data that is stored on your computer to that blank SD card.
If your SD card gets eaten by your dog...you won't lose anything except wave flow graphs.

All this means....you have your compliance data...and other data on the machine and nothing gets erased.
You have no worries.

Edit...Apparently the machine will start overwriting the daily detail data around 30 days.
Long term AHI data is still available along with compliance hours of use. So if the dog eats the SD card, detailed daily graphs are lost for nights over 30 days. It is still enough to see AHI trends. See my post below with report image.

Good to know. Thank You.

Pugsy wrote:... All this means....you have your compliance data...and other data on the machine and nothing gets erased.
You have no worries.

There are four different levels of data being saved each night: high-, medium- and low-resolution data, plus compliance data. High-resolution data will include things like flow and oximetry, if your machine is set up for it. Medium resolution will include things like apneas, hypopneas, their duration and time. Low resolution data includes things like AHI for the night and other nightly totals or averages. A week of high-resolution data is usually saved on the machine, with the oldest data being deleted to make room for the most recent data. Similarly, medium resolution data contains just the last thirty days of medium-res data. Low-res data generally stays on the sd card for a year or longer. Compliance data stays on the card for the duration of the machine's life. This kind of database is similar to a 'round-robin' database, where older data is culled to make room for newer data.

If you forget to put your card in the machine for a night, your high-res and/or medium-res data may be missing for that night, but the machine will sync with the card to make sure at least compliance data, possibly some medium-res and probably other low-res data are properly put back on the card.

This is one of the reasons why the megabytes of the data in the card seems to hover at about the same size even though the data themselves are actually constantly changing. So, the insurance-required information is not erased, but each night, old information is generally pruned out.

I hope this helps.

I just did a test with a blank SD card and my machine and Encore Viewer and a completely new user profile.
As of today..I have AHI and compliance summaries available back to when I first used the machine in October.

Looks like 30 days worth of daily detailed graphs before the detailed data starts to be overwritten on the machine itself.

So if someone doesn't download within 30 days potentially the older detailed graphs will be lost but the AHI summaries, PB, pressure and hours of use is still there in the final summary page.

For some reason I am having problems getting SleepyHead to import this data..even with a new user created. If I can get it to work and spot anything different I will edit this post.

Edit...got SleepyHead to work...see image of overview report. Dec 8 through 23...I was using a ResMed machine and 26 through 29 I was using M series machine. I do have daily detailed graphs for the 24 though. So we know the machine saves all data except flow rate for at least that number of days. I can't tell for sure when it starts being overwritten because of the ResMed usage nights. I would suspect 30 days though. I don't have daily details for 12/8.

btown wrote:Also when I put the card in the cpap it says new SD card detected and has a little elipsis that constantly cycles for 30-40 secs. (seems like its formatting the card)

Mine says "Data activity, do not remove card" when I insert a card and only takes a few seconds. That does sound like something is wrong with the card. Try another card.

In theory, your machine will remember your compliance data even without a card, and will write it to a card once you put a good one into the machine.

I got to thinking. I installed Encore Viewer 2.0 on this computer mid July..new computer. I put my SD card in from my PR S1 APAP that I bought last of April. I remember checking my April data in July and I know I had all the detailed daily data. I remember thinking how cool...it's all on the SD card. Maybe I dreamed it but if I can fire up the old computer that this one replaced...I will see what it had for older dates. I didn't put Viewer on that computer until early summer.

My observations have been the the detail data in the DataLog folder is wiped out on the card when you reinsert it, but the summary data is rewritten back from the S9 to the card.

JeffL wrote:My observations have been the the detail data in the DataLog folder is wiped out on the card when you reinsert it, but the summary data is rewritten back from the S9 to the card.

Doesn't the OP have a PRS1 machine?

archangle wrote:

btown wrote:Also when I put the card in the cpap it says new SD card detected and has a little elipsis that constantly cycles for 30-40 secs. (seems like its formatting the card)

Mine says "Data activity, do not remove card" when I insert a card and only takes a few seconds. That does sound like something is wrong with the card. Try another card.

That IS completely normal. However, you are permitted to think whatever you choose.