Question about GTR in Perdix AI

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Correction, Dive Log has a sidemount mode and does average litres per min calcs, the Perdix itself does SAC and GTR calculations from one TX or the other.
Ok, thanks. Thought so but was confused.
 
FYI from SW:

"The GTR calculations on the Perdix AI are only for single-tank diving that does not require decompression stops.

GTR is a tool for no-stop (i.e. no decompression) diving. We do not recommend GTR as a tool for decompression diving. Decompressing diving involves significant pre-planning of gas reserves and typically requires multiple tanks and gas mixtures. The complexities due to managing multiple tanks and differing styles of gas management would make setup of GTR too complex for reliable use. We tried this during development, and experienced testers frequently made setup mistakes that resulted in incorrect GTR. Shearwater feels that GTR is a great tool for single-tank, no-stop diving, but unfortunately does not work well for more complex diving."

from How is GTR calculated for multi-tank dives or decompression dives? - Shearwater Research

and a fair bit of anti-GTRness from Tech divers in general. The main point is being that it might allow divers to be lazy with gas management rather than using it as a verification tool. More info here: Do any Tec-Rec (or light deco) divers use GTR?
 
So, does the Perdix not calculate SAC rate?

I'm a little confused on the difference between SAC rate and GTR.
sac is consumption rate. gtr is how much time you have to reach your designated onboard pressure. IE you are set to be on board with 500 psi ad you have 750# YOU ARE AT 100 FT AND THE COMPUTER SAYS AT 50 psi a min you have 5 minutes. if you went up to 30 ft the time would change to 10 minutes because the consumption rate would be less. TTS is different in that it is (either) the time it will take to go to the surface at designated ascent rates or the time till you have to start your ascent. I dont remember which for sure. Its been a long time since i have used an AI computer.
 
FYI from SW:

"The GTR calculations on the Perdix AI are only for single-tank diving that does not require decompression stops.

?

perhaps it should be reworded a bit to say single air source. a set of doubles is a single tank when the crossover is open.
 
https://www.shearwater.com/products/peregrine/

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