Help with Suunto Cobra Please

[latitude]

Nope... it has nothing to do with ascent rates, reverse or sawtooth profiles or stuff like that - although they may contribute to the symbol, they're not the only reason it comes on.

All the manuals state is that when it appears (the triangle when in surface mode), you should extend your surface interval (it doesn't tell you how long, but if you're really curious, you can use the simulation mode and add surface time till it goes off). I dive a Vytec and have noticed it will come on exactly 5 minutes after I surface (when the computer terminates your current dive - according to the manual), and will dissappear at just over an hour.

I don't know if it penalizes you on the next dive (the manual isn't very clear) although I'd assume it does if you start the dive with the symbol on. When you download the data to your PC, you'll see the "violation" symbol on the profile if you started your dive while the symbol is on. (Was the symbol on the profile at the start of the dive?).

Now for the speculation: From what I've read and heard, the algorithm says that immediately after surfacing is the prime time for microbubble formation and that's why it comes on every time (like I said, I don't think I've ever finished a dive and not had the symbol - and I've done lots of shallow, very slow, smooth, non-sawtooth/reverse dives).

 

[lisa_j]

Aha - so what happened here was that the symbol likely came on at the end of dive 3 when I hit the surface, and I didn't notice it (because I'm not trained to look yet). After a 45 min SI I went down again, and that's when the violation occoured - hence the "violation" in the log on the descent of dive 4. Makes sense. I will pay closer attn to this in the future.

Would my dive still be safe if I stayed within the NDL and honored the safety stop? My NDL was something like 50 min when I started my ascent on dive 4.

Lisa

 

[Diver Dennis]

The symbol shows up on the dive log of the NEXT dive if you decend with it still on. When it comes on after the dive you are supposed to extend your surface interval until it goes off. I'm not sure if there are any penalties but in my use it does not seem to affect my next dive.

 

[latitude]

Aha - so what happened here was that the symbol likely came on at the end of dive 3 when I hit the surface, and I didn't notice it (because I'm not trained to look yet). After a 45 min SI I went down again, and that's when the violation occoured - hence the "violation" in the log on the descent of dive 4. Makes sense. I will pay closer attn to this in the future.

Would my dive still be safe if I stayed within the NDL and honored the safety stop? My NDL was something like 50 min when I started my ascent on dive 4.

Lisa

Plenty safe... No problems... If the "violation" were a factor, the computer would have shortened your NDL for the 4th dive (again, I can't get an answer on whether it does, and probably won't unless I can see the algorithm's code).

The triangle doesn't trigger a mandatory safety stop... I've seen those called for when I've done the things mentioned above (sawtooth profiles, ascent rate violations, etc...) The computer will tell you you've got a mandatory safety stop by putting the STOP symbol above your NDL display while you're at depth... kinda like "hey stupid, you messed up so you're going to HAVE to stop at 15 ft when you ascend this time..."

If you go into deco (ie let your NDL go to 0), you'll get an ASC TIME symbol while at depth with a CEILING readout to do the deco. You don't want to do that - you just entered the tech diving world...

Although it's kinda cryptic on how it works, the manual is pretty good about "what do I do when this thing comes on". Also, I'd suggest spending some time with the simulator. Do some crazy deep dives, stay past the NDL, do some huge ascent rates, and see what the computer does. At least the first time you see the symbols won't be underwater...

Dive Save!!!

 

[lisa_j]

Plenty safe... No problems... If the "violation" were a factor, the computer would have shortened your NDL for the 4th dive (again, I can't get an answer on whether it does, and probably won't unless I can see the algorithm's code).

The triangle doesn't trigger a mandatory safety stop... I've seen those called for when I've done the things mentioned above (sawtooth profiles, ascent rate violations, etc...) The computer will tell you you've got a mandatory safety stop by putting the STOP symbol above your NDL display while you're at depth... kinda like "hey stupid, you messed up so you're going to HAVE to stop at 15 ft when you ascend this time..."

If you go into deco (ie let your NDL go to 0), you'll get an ASC TIME symbol while at depth with a CEILING readout to do the deco. You don't want to do that - you just entered the tech diving world...

Although it's kinda cryptic on how it works, the manual is pretty good about "what do I do when this thing comes on". Also, I'd suggest spending some time with the simulator. Do some crazy deep dives, stay past the NDL, do some huge ascent rates, and see what the computer does. At least the first time you see the symbols won't be underwater...

Dive Save!!!

Excellent, will do. Thanks!

 

[robpauley]

Man I pick my Cobra up Tuesday. I hope I have enough time to play with it b4 I dive. My Lux is so simple I may regret buying a new one.