CC - PPO2 higher than SP - Display

[Frank]

Hi all,

running the simulation on ZL-16GF-CC I went to depth where I exceeded the Setpoint PPO2 due to the Diluent..
eg. SP 1,25 bar pPO2 Diluent Air Depth 60 m
I noticed that unlike expected no pPo2 warning showed up even when I set the CF19 show PPO2 was set as low as 20.
The display was working well with the ZL-16GF-OC
I wonder now if the DC reflects at all the higher pPo2 in the decopression clalculations?
Also will this display option be implemented (or already is in the new beta) ?

Another thing I notcied is that it seems that the temperature sensor is quite fast affected by the temperature of the DC itself..
After running simulations for about 30 min it is showing about 10 °C higher ambient temperature.

Bye,
Frank

[heinrichsweikamp]

Hello Frank,

When using fixed-SP the OSTC will calculate your deco on this Setpoint. Right now (in the 1.55) the Setpoint will be adjusted if it's physically not possible (e.g. 1,6Bar ppO2 in 3m Depth). The corrected Setpoint is displayed then. Most likely you're still using the 1.50.

Regards,
Matthias

[Frank]

Hi Matthias,

ok great. Looks like the 1.55 is solving most of my concerns right from the start
So I look really forward to the next stable and yes, currnetly I am using 1.50 as delivered..
Would it anyhow be possible to adjust the firmware in the future that in CC Mode the current diluent's ppO2 is displayed like it is in OC as a pure function of O2 fraction vs. current depth? This would really be great and helpful on CC dives for cell verification during a dive by flushing with diluent. Otherwise currently my procedure for this is to get to the closest most convenient "round depth" and then calculate the required PPO2 in relation to the ambient pressure, then flush and see wht the O2 cells are doing..

This would in my opinion be a much better help and asset of the DC as any Fisherplug ever could have been!

Thanks,
Frank

[Frank]

Hi Matthias,

I have been diving the OSTC now in the Red Sea on a couple of CCR Trimix dives. Works quite well with the 1.6 now.
Also I detected the "physical possible concept" for the Setpoint working well during the last bit of ascent. However looking to the phase of the dive my feeling and experience is, that this does not change a lot for decompression calculations etc. as this is usually only occuring right befor the last bit of ascent where you only spnet very little time anyway.
I also think that if a set setpoint is exceeded by the diluent already that it is still calculating with the fixed setpoint, which is a bit of a bugger.
On one dive for example I forgot to switch the Computer from my first low setpoint of .65 bar PO2 to 1.25 and such it seemed to calculate all the way with .65 even if the diluent at that dive was air and a considerable amount of time was spent at about 42m where thus already the diluent had a PO2 of almost 1.1 bar..
Would it be possible to implement that the Computer would be calculating always at minimum the physical PO2 at minimum even if the fixed SP is set lower?

Also what about the idea to also show the diluents PO2 in the display using the CC-Logarythm like it is shown in OC-Mode? Would this be possible to implement? This would be really really helpful.

Last but not least today I had the first not so pleasant experience with the Computer. It concerns the battery status info.. When I started an app, 60 min dive the Computer was showing the battery half full at descent. During the dive the battery went down to 1/4 and from then shut off within aboit 2 Minutes. Is this due to the fact that the battery has not been charged with a full cycle yet or do I have to count on a quite fast "crush-down" once half capacity is reached and shown?
If the latter it would be good if the "warning" of the battery status shown during the dive would hit in earlier than at half capacity.

Bye,
Frank

[heinrichsweikamp]

Hi Frank!

> not change a lot for decompression calculations
> etc. as this is usually only occuring right befor
> the last bit of ascent where you only spnet very
> little time anyway.

Correct - difference in deco is minimal.

> I also think that if a set setpoint is exceeded by
> the diluent already that it is still calculating
> with the fixed setpoint, which is a bit of a
> bugger.

This bug has just been fixed. 1.61beta will be released next week.

> Would it be possible to implement that the
> Computer would be calculating always at minimum
> the physical PO2 at minimum even if the fixed SP
> is set lower?

Done.

> Also what about the idea to also show the diluents
> PO2 in the display using the CC-Logarythm like it
> is shown in OC-Mode? Would this be possible to
> implement? This would be really really helpful.

It's now a combined output and I personally think it's better this way. One figure that shows your Setpoint/ppO2. Even if you violated your Setpoint you can still see/select it in the dive mode menu.

> went down to 1/4 and from then shut off within
> aboit 2 Minutes. Is this due to the fact that the
> battery has not been charged with a full cycle yet

Already fixed in the 1.61beta. These lithium batteries are a pain when trying to measure the capacity reliable. We now changed the battery symbol range and added a lot more margin to it.

We strongly recommend to recharge the battery completely when the bar is showing 50%.

regards,
Matthias

[Frank Herbert]

heinrichsweikamp Wrote:
-------------------------------------------------------
> These lithium
> batteries are a pain when trying to measure the
> capacity reliable. We now changed the battery
> symbol range and added a lot more margin to it.
>
> We strongly recommend to recharge the battery
> completely when the bar is showing 50%.


What does it mean?
The user has to calculate with only the half of announced battery capacity?
This can't be a good decision, even if the warn-message is changed by software.
What about a secundary battery, a capacitor, a energy saver mode..?
Or, at minimum, a reliable method of measuring the remaining battery capacity.
For me it's not acceptable, if a dive computer fails because of such a problem within a dive.

[Frank]

Hi Matthias,

Great to hear that the SP 'violation' will be fixed with the next release and that you are working on the battery issue.
For me that's fair enough..

'It's now a combined output and I personally think it's better this way. One figure that shows your Setpoint/ppO2. Even if you violated your Setpoint you can still see/select it in the dive mode menu'

In regards to the display of the physical pO2 of the diluent, I disagree slightly. Personally I would really like to see the diluents pO2 at all times.
This way you could always use this to check your cells with a diluent flush easily if in doubt at depth. Here I ususally now have to decent/ascent to a 'round depth number' and then start to calculate what the PO2 should be.
With the diluents PO2 always shown, you could just flush diluent quickly, compare values and commence the dive normally (or not)

Thanks anyway for the great support so far!
I now am a bit dissapointed that I bought a VR3 first and not two OSTC (redundancy!) Right away, since even the VR3 completely failed this vacation and since 6 days no response at all from the technical support! Not even a : sorry we can't help via email!

[Kim]

I agree with Frank, would be a great feature to see the active diluents ppO2 "online" for cell check in the CC-mode.

However, I don`t know where it should be put, it`s getting a bit crowded on the screen..

[Frank]

The place should be the least problem in CC Mode..

The place where the PO2 in OC Mode is shown would be just fine..
Should not interfere with any data from CC mode, or do I recall wrong from my memory?...