PfcAJ
Contributor
one of the problems i have w/ computers.
Tec computer with Trimix and A.I., is Suunto HelO2 the cheapest option?
- Thread starter kr2y5
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
Let's not confuse one manufacturer's product design/liability decision with the understood volume of physics and physiology available on the topic. The diver needs increased PO2 and increased ambient pressure. If Sunnto decided that can't be achieved using their computer in the water - okay fine. However, we're starting to see IWR become more and more pervasive.
Question for tracydr: Does the version of RGBM you have on your Xeo lock you out if you violate its deco recommendations?
---------- Post added January 10th, 2014 at 02:29 PM ----------
Vplanner(at +2, with 50% and 100%) shows stops beginning at 170' for that dive, with an 88 min run time--that's a little more than "not far"!
Last edited:
KD8NPB
Contributor
Unless you're in the water following Navy 5 recompression tables, it's not IWR, it's omitted deco which is within the prescribed 3 minutes time that the computer allows you to violate the ceiling. If you violate the ceiling for 3 minutes, then it assumes the same as if you left the water for 60 minutes : According to the math in the HelO2, you're bent, there's no going back, N2 is fizzing out of solution in your blood. That may not physically be the case, but it is what the math is calculated out to be.
---------- Post added January 10th, 2014 at 02:38 PM ----------
The Scubapro/SOS Decompression Meter didn't have lockout either...
You are correct : The calculated table using Suunto's software shows stops at about 170 ft as well. However, the ceiling is about 60 ft. (This assumes 35/25, EAN50, and EAN99 deco gasses by the way!).
I'll take a screenshot when I get home.
- Messages
- 2,739
- Reaction score
- 769
- # of dives
- 500 - 999
No, of course not. I would not have a computer that locked me out. The version I have is from Brian, of Free Phase One.
I would never have a computer that locks me out, especially with the fact that I'm planning to start cave and tech training soon.
---------- Post added January 10th, 2014 at 12:44 PM ----------
Actually, I'd say the computer is " bent". I wouldn't say the diver is bent unless he has symptoms of DCI. I can't imagine going to get decompressed in a chamber just because my computer doesn't agree with what I did. What if you're following a different profile, like in John's example?
I also think Highwing is talking about true IWR, which has been discussed at length on other forums.
GCullen94
Contributor
KD8NP8, Thats so far from the truth. Just because you violate what a computer tells you because you're following a precut plan doesn't mean that nitrogen is fizzing out of you. Please read Deco for Divers and learn what you are trying to talk about. Look at the differences in plans in VPM between nominal and plus 5, look at VPM FBO and the BE settings. Play around with the GF's while you're at it. I know people that get bent on any kind of VPM profile because their body's don't take well to deeper off gassing but prefer long shallow stops. I know people that can stop deep and have very little time in the shallows. It's all about managing your deco.
I think you don't understand what the SW does. If you miss a deeper stop than what it gives you, it RECALCULATES the plan to get the nitrogen out of you. More shallow time will be added to make up for missing the deep portion. Similarly if you follow a VPM plan and your computer is running 35/85, It will credit you for spending time deep and take away some of the shallow time. Please realize that just because you don't do exactly what your computer tells you, you are bent. That is far from the truth. Also the NAVY considers a 2% DCS hit rate to be acceptable, most people don't.
I think you don't understand what the SW does. If you miss a deeper stop than what it gives you, it RECALCULATES the plan to get the nitrogen out of you. More shallow time will be added to make up for missing the deep portion. Similarly if you follow a VPM plan and your computer is running 35/85, It will credit you for spending time deep and take away some of the shallow time. Please realize that just because you don't do exactly what your computer tells you, you are bent. That is far from the truth. Also the NAVY considers a 2% DCS hit rate to be acceptable, most people don't.
I'm sorry, but that is not remotely true.
Let's begin with the fact that there is no such thing as an established dark line for decompression. The algorithm tells you what it thinks is a range of safety. If you stay within its limits, you are most likely going to be fine, with the probability of you not being fine getting a bit greater as you get near the limits. The probably increases the more you surpass the limits. At 3 minutes past the ceiling, you are likely just fine.
Next, recognize that there is a big difference between computer algorithms, and there are algorithms that people dive every day all around the world that will put a diver more than 3 minutes past the Suunto alogrithm
As I believe I mentioned earlier, the one time my team had a Suunto HelO2 with us (just for the heck of it), we were following a V-Planner schedule perfectly. The Suunto went into Error mode during our 30 foot deco stop. We had apparently violated the ceiling to the point that it figured we were bent. We were still perfectly on track with the V-Planner schedule. We followed that schedule to the end, surfaced feeling just peachy, and tossed the useless HelO2 in the bottom of a gear bag.
In contrast, I did a dive with another team using a V-Planner schedule, and this time I had a Shearwater Predator with its Buhlmann algorithm with me. It wanted a completely different ascent profile. Again, we followed the V-Planner schedule perfectly as we ascended from more than 300 feet. I kept glancing at the Shearwater to wee what it would do. It was constantly telling me to do something different from what we were doing, but it was also constantly adjusting to the reality of our dive. It kept adjusting all the way to the end of the dive, and it actually cleared me to surface the same time the V-Planner schedule did. If I had surfaced without clearing it, it would have accepted the fact that I had used a different plan for my ascent and kept on working.
There are lots of reasons why you might not do what the computer tells you to do. One reason is so that you can keep your team together by choosing to use one of your computers as a primary team guide, using the other as a backup in case of emergency. Another reason might be beyond your control--some sort of emergency might force you to alter your plans. I think a computer that will quit working for you in mid dive in either case is close to worthless.
Dr. Lecter
Contributor
Nevermind, already covered.
If I may pile on... Which is why the subtle features of the Shearwater are brilliant. The SW computers are essentially running two models at once; your intended GF and also a GF99 option. Should you get stung, cut, or otherwise inured, or run low on gas for some reason, you could make a "GF99 exit".
The Shearwater feels like a little fighter on your wrist. No matter how much you make it angry you can click "Confirm" and it keeps up nicely.
Similar threads
