Question I can't get my Perdix AI to accept two tanks with the same ppO2

[JohnN]

I have a transmitter on my back-gas and one on my pony/stage bottle. (FWIW it's a pony in cold water when I have a big steel on my back and a stage bottle in warm water with an AL80)

I've forgotten how to set it up so both tanks can have the same ppO2. This should be the same as diving sidemount. . .

When I try to define gases in "Dive Setup" --> "Define Gas" Gas 1 and Gas 2 have to be different.

I know I can make one .21 %O2 and the other .22 %O2 (close enough for government work), but how do I make them the same?

 

[rongoodman]

I think you’re confused as to what Gas 1 and Gas 2 mean. They refer to different mixes you have available for travel, bottom, or deco use, not which tanks they're in. Your Perdix needs to know when you change gases so it can continue to make accurate deco calculations. If both tanks contain the same mix there is no need for switching between Gas 1 and Gas 2 when you change tanks and in fact any other gases defined should have been turned off. T1 and T2 show the pressure in each tank but have no idea what's in them.

 

[stuartv]

What Ron said. Just leave your gases with 1 gas defined.

Go into the AI setup to configure your 2 transmitters.

If the tanks are not identical in size, then you should not use Sidemount mode. At least, the GTR part of SM mode will not work correctly unless both tanks are the same size.

Then you can do a widget for your home screen that shows T1 and T2. The actual gas mix for each transmitter doesn't matter, as the computer treats the gas you're breathing as independent from the cylinder pressures shown by the AI. You're only breathing one gas at a time and whatever that is is all the computer needs to know.

 

[Bloody Marvelous]

What was said before.
You have different transmitters (T1-T4), and you have different gas mixes (up to 5).
Transmitters aren't linked to gases, they're linked to cylinders. It's up to you to know what gas is in what cylinder, hence you should mark your cylinders clearly when diving with multiple gases.

If you're diving one gas mix, make sure it's the only one active in your computer. If you have more mixes active, your dive computer will inform you when you should/can switch to a different mix. It won't tell you to switch to the cylinder with the T2 transmitter.