Will Air Integration in dive computers replace the SPG?
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DevonDiver
N/A
In respect to diving...shouldn't the subjectivity be weighed on the ease and logic of the mathematics involved for calculating depth, pressure and gas?
The metric system is very intuitive for divers.
1atm = 10m
1bar = 1 atm
- 6 litre tank @ 200 bar = 1200 litres of gas (6 x 200)
- Diver breathes 20 litres per minute at the surface
- Diver goes to 30m
- 30m equals 4 atm (30 x 4 -10)
- Diver consumes 80 litres per minute (20 x 4)
- Diver has 15 minutes of gas at 30m (1200 / 80)
I'm cr@p at math... but I can manage all the necessary calculations for diving in my head if I use metric. The imperial system requires much more complex math.... and that is a drawback.
Kevrumbo
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SPG (or AI) instrumentation is in units of bar pressure, so transform that SAC-RMV of 20 liters/min per ATA to pressure units:
20 liters/min*ATA -divided-by- 6 liters/bar tank equals: 3.3 bar/min per ATA.
(Easier to work arithmetically with 3.3 bar/min per ATA than it is with equivalent 47.8 psi/min per ATA in US Imperial units).
At 30 meters depth which is 4 ATA (i.g. 30 divided-by 10 and add 1 equals 4 ATA), the 3.3 bar/min per ATA at 4 ATA depth becomes 13 bar/min (i.g. 4 times 3.3 equals 13 bar/min).
Five minutes elapsed time at 30m depth, you will consume 65bar of gas (5 minutes multiplied-by 13bar/min is 65bar); 200bar full tank minus 65bar equals 135bar remaining as indicated by your SPG (or AI).
Five more minutes for a total of 10 minutes elapsed time, you expect your SPG (or AI) to be down another 65bar for a remaining pressure of 70bar (135 minus 65 is 70); by 15 minutes elapsed time, you will be out-of-gas (70 minus 65 is 5bar remaining) at 30 meters depth --hopefully you will be switching to larger supply of backmount or sidemount bottom mix cylinders by this time. . .
So okay y'all US Divers with AI, keep your AI modules and use 'em to learn the Metric System --you will eventually be performing gas consumption real time just as fast --and more importantly-- verifying the readings of your digital AI instrument.
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HAHAHAHAHAHA
Nonsense indeed.
5 years ago all the same comments were made about using a computer by Tech divers.
All about failure points, all about unreliable, all about batteries discharging. Same kind of comments, must have a watch and a bottom timer, no computer needed, not worth it you're gonna die.
Nonsense indeed.
5 years ago all the same comments were made about using a computer by Tech divers.
All about failure points, all about unreliable, all about batteries discharging. Same kind of comments, must have a watch and a bottom timer, no computer needed, not worth it you're gonna die.
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DevonDiver
N/A
packrat12
Contributor
5 years ago the technical computer selection was slim and expensive. The computers now are very reliable and inexpensive. They offer a lot of advantages with limited risk and failures. Wireless AI has a couple of minimal advantages, especially to a tech diver, but has a significant disadvantage with respect to synchronization and failure points. So lets see from a technical point of view... Computer has actual dive profile and decompression schedule. Can be adjusted for different gasses and GF on the fly.... Can be adjusted for different profile on the fly... etc. Wireless AI (or AI) offers pressure information. (Already got it from SPG). Offers air time remaining - Meaningless to technical diver as they use multiple tanks and planned turn pressure. Gives SAC rates - Yea that one is nice. Ability to monitor multiple tanks - Maybe advantage for sidemount but for a backmount diver I really only care about my back gas so 1 gauge will do. As a CCR diver, I really do not need continuous monitoring of either gas so an occasional check will do.
So for the added complexity of AI as a technical diver I get...... my SAC rate.
So for the added complexity of a computer as a technical diver I get...... Current deco schedules, different gas planning, different GF planning, accurate profile logging, emergency ascent schedules and more. I still can carry watch/depth and tables.
I think it is clear why computers entered the technical market. I get very little from AI entering the technical market.
Oh and DevonDiver - Love the new logo!!
And after 3 more paragraphs of the same type of talk as was seen 5 years ago the fact remains that tech divers were against the use of a computer for tech dives.
DevonDiver
N/A
Why does everyone keep saying "5 years ago"??? It's like 'tech computers didn't exist before Shearwater.....??
5 years ago.... tech divers were salivating at the X1....
5 years before that.. VR3s, Cocherans etc were everywhere...
Is this a regional thing? I'm missing something.... because I was teaching tech 5 years ago...and this deficit of tech computers seems to have passed me by.... LOL
5 years ago.... tech divers were salivating at the X1....
5 years before that.. VR3s, Cocherans etc were everywhere...
Is this a regional thing? I'm missing something.... because I was teaching tech 5 years ago...and this deficit of tech computers seems to have passed me by.... LOL
5 years ago tech divers were saying that computers would not be used by mainstream tech divers. You were probably one of them.
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