Atom2 PO2 alarm comes on early

[Doug Krause]

Perfect, let me know how it goes.

 

[adjuster-jd]

I too am diving 2 oceanic computers - the Pro Plus II and the Atom 2. The Atom is beeping high PO2 alarm and the ProPLus is not. Both are set to 1.4 ATA.

 

[Divingguy]

OK. I fired up both the VTPro, and the Atom2, and put them both into "settings" modes. Although the software is organized differently, I confirmed that every single setting, DTR, ATR, Turn, and End, were identical. The only thing that could NOT be "matched" were the TLBG settings. The VTPro had like 8 dots max to choose from, while the Atom2 had only 5. I think that this is where the difference is, and can not figure out how to reconcile them.

 

[Fordan]

So is it that if we want the fairly standard 1.4 with 1.6 as a contingency, we need to set to 1.6, so that it'll start alarming at 1.4? And then will it really alarm at 1.6? What value is used in calculating the MOD?

edit: and why would TLBG be involved in PPO₂ alarming?

 

[Divingguy]

I am not saying that TLBG is or should be involved in true PO2 alarming. However, both the OP and I have had conflicting simultaneous readings from dual Oceanic devices, and I was trying to isolate what setting might be causing the Atom 2 to give me a warning to ascend due to high nitrogen, when the VT Pro did not. Same problem for the OP. If the Oceanic software is set to "alarm" .2 before the PO2 setting chosen, it still seems like BOTH of my units, which were set to PO2 1.6, should be giving me the same high nitrogen warning.

 

[Doug Krause]

There are two topics within this thread:

1. High PO2 warning. The following is the relevant page from the ATOM 2.0 Operating Manual > http://www.oceanicww.com/pdf/atom_manual_highPO2.pdf

2. High Ni warning as mentioned by Divingguy. This setting is tied to the tissue loading bar graph alarm setting. I am inclined to agree that the actual quantity of tissue loading bar graph segments varies per model, has bearing on the different results during the same dive. I will simulate this on both the ATOM 2.0 and VT3 to see if I can provide additional explanation.

Doug

 

[Divingguy]

Doug: thanks for the response. I agree, they seem to be separate issues, but are issues that both the OP and I are having. I certainly did not mean to hijack his thread. I will look forward to hearing back about how best to "match" the tlbg settings to eliminate the high ni warning.
Tom

 

[adjuster-jd]

I have no issue of N2 loading - my issue is the PO2 alarm coming on before the 1.4 setpoint. I know what my MOD is on the gas I am using. I want to have the alarm at that MOD not at some other depth. If I plan a dive to 110 feet on 31% I should not be getting an alarm at 95 feet telling me to go up. If I set the alarm at 1.6 then in plan mode the MOD will be wrong.
Doug / Darrel - I hope you can come up with an update here. Since we know that firmware updates can be done by the dealers this should be a pretty easy change to roll out. This is a $1000 computer - hopefully you can make this a little more user friendly.
Thanks.