Alternating Nitrox and Air dives ok on ProPlus 3?

[EFlyDive]

We're planning a liveaboard trip where Nitrox is available.

Will the ProPlus 3 continue to properly track gas absorption etc properly between dives if it is set for Nitrox on some dives and regular air on others during the trip? (I'm assuming so at this point.)

Eric

 

[tursiops]

yes

 

[jmb122mp]

It definitely works if you use the Nitrox 21% setting for air. If you use the air setting it may lock you into air mode until 24 hrs pass. Not 100% on this.

 

[tursiops]

It definitely works if you use the Nitrox 21% setting for air. If you use the air setting it may lock you into air mode until 24 hrs pass. Not 100% on this.

This is sort of backwards.
If set on air, you can change to nitrox at any time. If set on nitrox, 24h must elapse before it can be set on air, but you can just set it on 21% if you want to use air. Whether set for air or 21%, the internal calculations are the same, and it tracks but does not display MOD or O2 if set on air.
See manual page 13.

 

[EFlyDive]

This is sort of backwards.
If set on air, you can change to nitrox at any time. If set on nitrox, 24h must elapse before it can be set on air, but you can just set it on 21% if you want to use air. Whether set for air or 21%, the internal calculations are the same, and it tracks but does not display MOD or O2 if set on air.
See manual page 13.

Thanks! Good info.

If I set up gas 1 to 21% O2, and Gas 2 to 32%, I see how to select between these gasses underwater, but can I pre-select which gas ( 1, 2 or 3) I will use before the dive? (I've missed that looking through the manual.)

Alternatively , I can just manually change the gas 1 O2 % prior to each dive as needed.

 

[tursiops]

Manual, page 25, Gas Switching.
All dives begin with Gas 1; you can switch to Gas 2 underwater, during the dive.

Just set the O2% you have in your (single) gas before each dive.

 

[Freewillow]

This is sort of backwards.
If set on air, you can change to nitrox at any time. If set on nitrox, 24h must elapse before it can be set on air, but you can just set it on 21% if you want to use air. Whether set for air or 21%, the internal calculations are the same, and it tracks but does not display MOD or O2 if set on air.
See manual page 13.

I do not hava this computor, but why would it ne impossible to change the settings before 24 hours? What is the différence between 21% Nitrox and air? Everybody decompress with air @ the surface wether your computor is on air or nitrox. My wife does her second dive on nitrox quite often. Never had a problem, but we have Uwatec computors. Just curious.

 

[tursiops]

I do not hava this computor, but why would it ne impossible to change the settings before 24 hours? What is the différence between 21% Nitrox and air? Everybody decompress with air @ the surface wether your computor is on air or nitrox. My wife does her second dive on nitrox quite often. Never had a problem, but we have Uwatec computors. Just curious.

The difference is in the display, not in the calculations. Your O2 buildup and MOD is displayed in nitrox mode, but not in air mode. Neither is important using air recreationally. So, if you are in nitrox mode, it stays that way until 24h passes, so you clear your system before starting with air again.

 

[Freewillow]

Thanks for the explanation, but for me this would be a major NO/NO .

When I am diving Nitrox on LOB, sometimes I prefer to dive on air for the first dive in the morning - sometimes the boats offer too high 02 Nitrox mixes for 150 feet . This means that I could not switch to nitrox later in the day.

 

[tursiops]

Thanks for the explanation, but for me this would be a major NO/NO .

When I am diving Nitrox on LOB, sometimes I prefer to dive on air for the first dive in the morning - sometimes the boats offer too high 02 Nitrox mixes for 150 feet . This means that I could not switch to nitrox later in the day.

No, that's backwards. You can always switch from air to nitrox, but must wait 24h to switch from nitrox to air.....or just switch to 21%.