PO2 dive computer warning

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Well, after reading through this I just had to look up the A300 manual.
First, most of the added functionality in the Tech mode is commonly available within general menus on other computers, both Pelagic and other brands. And most of that functionality can be ignored or opted out. (for instance, just don't set a Conservative Factor, and just don't turn on the Deep Stop in Tech mode if you don't want it.)

Regarding the PO2 audible warnings and alarms, I think I read conflicting guidance on my first pass. I am not so sure that setting your PO2 to 1.6 in Recreational mode will change anything for you. You might not even be able to, if I am interpreting this section correctly. (and alarms and warnings both appear to be audibles)
HIGH PO2
Warning, in NORM >> at 1.20 only.

Alarm, in NORM >> at 1.40 only, except in Deco then at 1.60 only.
Warning, in TECH >> at 0.80 to 1.40 (0.20 less than Alarm value set).

Alarm, in TECH >> at Set Point value, except in Deco then at 1.60 only


It looks to me like even in Tech you would have to set to 1.6 in order to avoid audible alerts prior to 1.4. Normally, I would strongly agree with those that are saying to NOT set your PO2 to 1.6. But since your computer is for all intents and purposes warning you off of anything greater than 1.4 when you have it set for 1.6, I would be comfortable with that setting.

In the PADI course we teach that 1.6 is a contingency value for planning purposes, in case we accidentally exceed 1.4. Seems that version of the Pelagic software is using that thought process but with a bit of a different (and confusing) spin on it.
 
My Oceanics don't alarm until the 1.6 setpoint.
Hi @BRT

What Oceanic computers do you have? I have several older Oceanic computers, Pro Plus 2s, VT3, Geo2, VT4. All of them show a visual warning when the pO2 is 0.2 below the set point. All of them show a visual alarm when the pO2 reaches the set point. The visual warning/alarm occurs whether the audible alarm is on or off. All of the newer Oceanic computers appear to work identically according to the manuals. Perhaps you are referring only to the pO2 alarm and not the mandatory warning. Both have an audible warning, if enabled.

I posted earlier that I set my computers at a pO2 of 1.6. I am always aware of the pO2 1.4 MOD for my mix, and generally, do not descend below it. When I do, I see the warning at a pO2 of 1.4 and, If I continue to descend, I see the alarm at 1.6. I find this is a perfectly acceptable way to deal with MOD and, at the same time, avoid unnecessary warnings/alarms. I also choose to have my audible alarms disabled. To each, their own.

This is from the VT4 manual:
upload_2019-3-17_12-12-34.png
 
Don’t turn off alarms. They are there to warn you. If you cant adjust them to warn you at the correct time then sell the computer and buy a much better one. Something from Shearwater is a first class choice. Your responsibility is to be smart. Wary. Attentive. Not manipulate your computer when it doesn’t think correctly. If it means you sacrifice dining out to save for a high quality computer - then do that.
 
Since I can't hear those high-frequency alarms anymore, I turn them off. Problem solved. My buddies thank me.
Since I'm usually wearing a nice, warm, thick, extremely snug neoprene hood, I can't hear those alarms. Period. Problem solved.

Although another problem is, it usually gets a mite difficult to hear anything else either.
 
Since I dive with a backup, I have at least learned to silence one of them. If I don't it isn't a stereo effect, more of a slow echo as they trigger a few seconds apart.
 
Don’t turn off alarms. They are there to warn you

I recommend turning off audible alarms- there's still the red flashing light to warn a diver that he or she has failed to monitor a crucial dive parameter. Doesn't mean the rest of the group and all the fish need to know it too.
 
Hi @BRT

What Oceanic computers do you have? I have several older Oceanic computers, Pro Plus 2s, VT3, Geo2, VT4. All of them show a visual warning when the pO2 is 0.2 below the set point. All of them show a visual alarm when the pO2 reaches the set point. The visual warning/alarm occurs whether the audible alarm is on or off. All of the newer Oceanic computers appear to work identically according to the manuals. Perhaps you are referring only to the pO2 alarm and not the mandatory warning. Both have an audible warning, if enabled.

I posted earlier that I set my computers at a pO2 of 1.6. I am always aware of the pO2 1.4 MOD for my mix, and generally, do not descend below it. When I do, I see the warning at a pO2 of 1.4 and, If I continue to descend, I see the alarm at 1.6. I find this is a perfectly acceptable way to deal with MOD and, at the same time, avoid unnecessary warnings/alarms. I also choose to have my audible alarms disabled. To each, their own.

This is from the VT4 manual:
View attachment 510293
Veo 250. I only know about the alarm because I accidentely had it set to change the mix after every dive and I started to hear an alarm around 70 feet. I suppose it could have started sooner. I was in a heavy hood and it took me a minute to figure out what the noise was.

Edit. It appears you are correct but the manual seems confusing. It says it will alarm at 1.4PP or .2 less than set at and the next part says it will alarm at the setpoint. Does that mean it stops in between? Doesn't matter. I turned off the audibles.
 
Veo 250. I only know about the alarm because I accidentely had it set to change the mix after every dive and I started to hear an alarm around 70 feet. I suppose it could have started sooner. I was in a heavy hood and it took me a minute to figure out what the noise was.
MOD for 50% O2 would be 59 ft for 1.4 and 72 ft at 1.6, see Necessity of a back up computer/watch for NDL diving
 
ooops! Wish I could figure out how to delete this post, as I now see that you identified the computer in another message. sorry!
What computer? This should be a configurable option.
It's been nearly a year since your original post, but I'd also like to know what computer you were using, topher10. Wondering if the issue is specific to that computer (in which case, I'd like to avoid buying it!).
 
https://www.shearwater.com/products/swift/

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