O2 sensor values on CCR dives

[Davide DB]

Given the good relationship between Subsurface devs and Shearwater
wouldn't it be easy to ask them some more info on this topic?

On 11 December 2017 at 16:53, Anton Lundin <glance at acc.umu.se> wrote:
> On 11 December, 2017 - Davide DB wrote:
>
>> On 11 December 2017 at 15:59, Anton Lundin <glance at acc.umu.se> wrote:
>> > On 11 December, 2017 - Davide DB wrote:
>> >
>> >> On 11 December 2017 at 10:16, Anton Lundin <glance at acc.umu.se> wrote:
>> >> >> I calibrate my two Petrels ALWAYS when I assemble my unit as part of
>> >> >> my checklist and ALWAYS the same day I dive and. No calibration No
>> >> >> party.
>> >> >> I made other dives and all of them show the same error. Shearwater
>> >> >> desktop tell me that everything is ok (like my Petrel underwater)
>> >> >> while Subsurface reports pO2 over 1.6.
>> >> >> Thank you for the detailed explanation.
>> >> >> Where do we go from here?
>> >> >
>> >> > Is this a divecan unit or something?
>> >> >
>> >> > I'm just guessing that it might affect how/where the cal factors are stored.
>> >> >
>> >> >
>> >> > //Anton
>> >>
>> >> Yes, divecan unit.
>> >
>> > There we go. Thats probably why its the factory default cal factors that
>> > are stored in the header, and not the real ones. It might be that the DC
>> > doesn't even have them, and its only the sensor board which know them
>> > for real.
>> >
>> >
>> > My suggestion then is to not show individual sensor ppo2's, if the cal
>> > factor is 2100, and just emit the average ppo2 then.
>> >
>> > At least that one is accurate.
>> >
>> >
>> > The best would be if we had a interface which let us both expose the
>> > average ppo2 and the raw mV values.
>> >
>> >
>> > //Anton
>>
>> Hi Anton,
>>
>> The strange thing is that also the other dataset from my dive friends
>> came from divecan units (JJ).
>> IIRC those dataset haven't this problem.
>
> When I read the thread again, from the snippets Jef posted all those
> have cal factors of 2100, so I'm guessing those ppo2-values are
> inaccurate to.
>
>
> Jef: could you verify this against the average ppo2 in those mem dumps?
>
>
> //Anton
>
>
> --
> Anton Lundin    +46702-161604



-- 
Davide
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