? for Suunto Computer Users

[Yeoh Chee Weng]

Thanks Vjongene & Geraldp. Come to think of it, I'll think Geraldp was right that I ascended faster than 39fpm because I wasn't near deco level. Before I bought the Cobra (this is my first dive computer) I was quite happy to ascend at 60fpm and did the safety stops for 3 min. at 15 ft. As I mentioned before I am still learning to reduce my ascend rate to comply with the Cobra's conservative rate. It seems that the Cobra's alarm is set at such a low volume that this feature is practically useless! I have sent my Cobra back to Suunto for repair and still waiting to get it back after a month.

 

[CelticRavenVA]

Geraldp, is not only slightly right he is exactly right on this. Not to mention the console is extreamly percicse in measuring these ascent rates.

Here is a real life example. We were doing a drift dive and were at our safety stop. Weather was starting to get bad and the surface was starting to get real choppy. It was lovely when we went down, we just came up to a very different, slightly angry ocean. *Waves at mother nature* We completed our safety stop which I was sitting at 18 feet for the entire time with no issues. I then got a very fast bounce from 18 feet to 10 feet due to surge and most likely having a bit to much air in my BC as I was completing my final ascent. Right there at 10 feet, the computer alarm is going off, please enjoy another 3 min at this depth which was a bit easier said then done with the surface conditions as they were now. However, I satisfied it in fear that some how I hit an NDL. Once we hooked it up to the computer I was able to see what happened.

My understanding of what this does is helps prevent micro bubbles from forming, but I will leave that to the dive med guru's.

Needless to say, I like and trust my Suunto, is it less agressive? Yes. Do I keep it in P1 to make it even less so? Yes. Do I want to get bent? What do you think?

vjongene is correct that the Cobra doesn't go into error by simply missing the recommended safety stop. It will definately go into ERROR if it tells you it wants a MANDATORY safety stop and you don't follow it's floor/ceiling guidelines.

The Suunto will give you a MANDATORY safety stop for two reasons: 1) Going into a decompresion dive (as vjongene states), or 2) continuously ascending at an unsafe rate. If you ascend between 33fpm to 39fpm it will beep at you and scold you, but it won't go into error. If you exceed 39fpm continuously it will flash STOP and give you a FLOOR/CEILING for a mandatory safety stop. Actually the ref manual states "above 39 fpm or continuously above 33 fpm". If you violate the resulting required safety stop it will lock out.

On my first dive with my Cobra in Cozumel earlier this year I lost control of my bouyancy on ascent and quickly (i.e. >39fpm) shot through the (recommended) safety stop. As soon as I hit the surface I immediately upended and dropped down to 15 feet and stayed for 3+ minutes. The computer showed I was at 0 feet during the whole safety stop! All subsequent dives the Suunto worked fine. When I got back I contacted Suunto to ask what happened. It turns out that I violated the >39fpm ascent rate AND blew through the safety stop the Cobra started to go into an ERROR mode. Because I immediately dropped back down to 15 feet (within the 20 second sampling rate) it took itself out of ERROR mode, but it remained confused for the rest of that dive. When I uploaded my profile it showed exactly what happened.

btw I have NEVER heard my Cobra beep underwater... perhaps because I usually wear a hood.

 

[CelticRavenVA]

Suunto can increase the volume on the cobra??? I think it is kind of quite as well... I didn't know they could do that. What did they say when you talked to them?

Thanks Vjongene & Geraldp. Come to think of it, I'll think Geraldp was right that I ascended faster than 39fpm because I wasn't near deco level. Before I bought the Cobra (this is my first dive computer) I was quite happy to ascend at 60fpm and did the safety stops for 3 min. at 15 ft. As I mentioned before I am still learning to reduce my ascend rate to comply with the Cobra's conservative rate. It seems that the Cobra's alarm is set at such a low volume that this feature is practically useless! I have sent my Cobra back to Suunto for repair and still waiting to get it back after a month.

 

[QuoVadis]

vjongene is correct that the Cobra doesn't go into error by simply missing the recommended safety stop. It will definately go into ERROR if it tells you it wants a MANDATORY safety stop and you don't follow it's floor/ceiling guidelines.

The Suunto will give you a MANDATORY safety stop for two reasons: 1) Going into a decompresion dive (as vjongene states), or 2) continuously ascending at an unsafe rate. If you ascend between 33fpm to 39fpm it will beep at you and scold you, but it won't go into error. If you exceed 39fpm continuously it will flash STOP and give you a FLOOR/CEILING for a mandatory safety stop. Actually the ref manual states "above 39 fpm or continuously above 33 fpm". If you violate the resulting required safety stop it will lock out.

On my first dive with my Cobra in Cozumel earlier this year I lost control of my bouyancy on ascent and quickly (i.e. >39fpm) shot through the (recommended) safety stop. As soon as I hit the surface I immediately upended and dropped down to 15 feet and stayed for 3+ minutes. The computer showed I was at 0 feet during the whole safety stop! All subsequent dives the Suunto worked fine. When I got back I contacted Suunto to ask what happened. It turns out that I violated the >39fpm ascent rate AND blew through the safety stop the Cobra started to go into an ERROR mode. Because I immediately dropped back down to 15 feet (within the 20 second sampling rate) it took itself out of ERROR mode, but it remained confused for the rest of that dive. When I uploaded my profile it showed exactly what happened.

btw I have NEVER heard my Cobra beep underwater... perhaps because I usually wear a hood.

Not to change the subject but i was taught that you NEVER go back down to comply with a missed safety stop............was i taught wrong?

 

[vjongene]

The Suunto will give you a MANDATORY safety stop for two reasons: 1) Going into a decompresion dive (as vjongene states), or 2) continuously ascending at an unsafe rate. If you ascend between 33fpm to 39fpm it will beep at you and scold you, but it won't go into error. If you exceed 39fpm continuously it will flash STOP and give you a FLOOR/CEILING for a mandatory safety stop. Actually the ref manual states "above 39 fpm or continuously above 33 fpm". If you violate the resulting required safety stop it will lock out.

Thanks for pointing this out. I had not realized that a continuous unsafe ascent would trigger a mandatory safety stop. Just never happened to me, and maybe I didn't read the manual carefully enough. But makes a lot of sense.

Victor J.

 

[geraldp]

Thanks for pointing this out. I had not realized that a continuous unsafe ascent would trigger a mandatory safety stop. Just never happened to me, and maybe I didn't read the manual carefully enough. But makes a lot of sense.
Victor J.

The manual is not an easy read, and I haven't figured everything out yet. My Cobra flashed the word "CEILING" at me towards the end of my second dive last Sunday. By the time I got to my safety stop it disapeared. When I looked at the Cobra in logbook mode and later downloaded into Suunto Dive Manager I saw no record of it. Unfortunately I didn't pay enough attention to notice the ceiling depth it was telling me.

According to my graph, it looks like I got the SLOW indicator early on in my dive, so I'm guessing that's what the CEILING notification was about. I obviously kept under the ceiling for the allotted time, as the computer didn't complain any further.

Don't beat me up too much on my ascent rate... I'm still working on my bouyancy skills, and in my defense I was chasing an erant buddy.

Another user's manual complaint I have is about the tissue loading. I haven't found much information about what the heck that's about. According to the Dive Manager manual, it says to read the Cobra manual and consult your Dive Shop. The only useful tidbit I gleaned is that you don't want any tissue grouping to exceed 100% - if it does you'll go into deco mode.

 

[miketsp]

Not to change the subject but i was taught that you NEVER go back down to comply with a missed safety stop............was i taught wrong?

The question here is timing.
If you overshoot your "deco ceiling" most computers will give you a few seconds to get back down before going into error.
Now if you have surfaced and started to show DCI symptoms then in-water deco is never recommended. Get on O2 and get to a chamber.


Again if you overshoot your "safety stop" and can get back down quickly then I understand it's worth it.

 

[CelticRavenVA]

My experience with the cobra is the same. I drifted over 10 feet one safety stop, and got back down to 15 pretty quick. It just made me stay there for another 3 min. (It reset the time for the safety stop.)

The question here is timing.
If you overshoot your "deco ceiling" most computers will give you a few seconds to get back down before going into error.
Now if you have surfaced and started to show DCI symptoms then in-water deco is never recommended. Get on O2 and get to a chamber.


Again if you overshoot your "safety stop" and can get back down quickly then I understand it's worth it.

 

[cornfed]

According to my graph, it looks like I got the SLOW indicator early on in my dive, so I'm guessing that's what the CEILING notification was about. I obviously kept under the ceiling for the allotted time, as the computer didn't complain any further.

Don't beat me up too much on my ascent rate... I'm still working on my bouyancy skills, and in my defense I was chasing an erant buddy.

That might be the reason it was yelling at you. If you exceed what maximum ascent rate for a period of time it will display "CEILING" to indicate a mandetory safety stop. Or if your dive extends past the NDL times the computer will display "CEILING".

You seem to be putting quite a bit of trust into something you don't understand. I would seriously suggest you learn how to use your computer if you're going to continue diving with it.

 

[geraldp]

That might be the reason it was yelling at you. If you exceed what maximum ascent rate for a period of time it will display "CEILING" to indicate a mandetory safety stop. Or if your dive extends past the NDL times the computer will display "CEILING".

Please see my previous posts on this thread... basically saying what you just said.

You seem to be putting quite a bit of trust into something you don't understand. I would seriously suggest you learn how to use your computer if you're going to continue diving with it.

In the 20 some-odd dives I've put on this computer since February I've gotten the little SLOW diamond marker on my graphs several times. I've never seen the "CEILING" show up before. What I was confused about is why more details weren't shown in the graph/profile.

Most of us put our trust into things we don't fully understand every day. The best I can do here (visavis the Cobra) is read the manual several times, and then post questions here about things I don't understand (which I just did).