How to program Suunto cobra for nitrox

[SeahorseDeb]

I have a Suunto Cobra and desire to learn to program it for nitrox. Let's use an example of EAN 32. The instruction manual assumes I know how to move it from air mode to nitrox, which I don't . The shop I purchased it from is of little help, they don't sell anything except air and my instructor isn't certified for nitrox. I am not diving on Nitrox yet, I am studying for my certification with PADI, so I would like to be proficient with the computer from switching oxygen percentages and also switching back to air mode. The PADI dive shop I am studying under does not sell the Cobra.
The last question I had about the computer was answered by one of ScubaBoard's members. The manufacturer was of little help. I am grateful for instructions! Thankyou! Debbie

 

[NorthWoodsDiver]

Do you have the cobra, cobra 2, or cobra 3. I dont know how the 2 and 3 work but the oldest one is fairly straight forward.

there are 3 buttons, 2 on the bottom and 1 on the side.

so turn it on and select "SET" then "SET PREF" then "MODEL" then "NITROX"

then you will have to tap "QUIT" until your back to the mode screen

Now hit "SET" then "SET DIVE" then "NITROX" and you will see all the things to adjust. Set your PPo2 for 1.3 or 1.4 (normally or any other setting you desire but generally not over 1.6) and then set the % or O2 which in your case is 32.

you will automatically have a max depth appear based on the 2 settings which cant be adjusted without altering the PPo2 or the % or O2.

its pretty simple once you do it 2 or 3 times.

however watch out, if you accidentally click it into gauge mode instead of air or nitrox and then do a dive you will not be able to adjust any settings for 24 or 48hrs depending on which your computer is set at. I made that mistake once and wont do it ever again.

hope that helps.

 

[Starcruiser]

Hi Debbie - Press the mode button to start the computer. When it cycles, press the mode button again. then press the plan (left bottom) button. set should be visible. Press mode again, then time (right bottom)button twice. setpref should be visible. press mode, then time 3 times. model should be visible. Mode again, the two time button again to select nitrox. the mode again to accept the change. To change the % O2 after you select nitrox, press mode, time 3 times, mode, time once to setdive, mode, time 4 times to nitrox, mode, then use the arrow keys to input the correct % and PO2
Simple, huh? Note sarcasm...... It took me a while to get it right. Hope this wasn't to confusing...

 

[eponym]

Setting options on the Corba 2 and 3 is much different from the original Cobra. You can download the manuals from the Suunto site and they're easier on the eyes as PDF files than the small printed version that comes with the computer.

One thing to know: Suunto expects you to round down the oxygen percentage of your mix before entering it, and it then adds one percent (without announcing or displaying that fact). So for example if your gas tests out to 31.6, enter that as 31. The computer will assume the actual value was something over 31 and use 32 to compute your MOD.

That is why the Cobra's displayed MOD may look a tad shallow compared to your nitrox tables.

-Bryan

 

[SeahorseDeb]

Well, I found the step I was missing. Hmm, interesting how a person can work for hours on a problem, step away from it, post a question, and then go back and find the answer! Label me: I have a new question, so will post that now!

 

[SeahorseDeb]

Now that I have figure this out, (I wasn't pressing the mode button twice as StarCruiser mentioned. Now my last question. I don't see why I need to change it back and forth from air to Nitrox based on which ones I am using on a given day or week. Can't I just leave it on nitrox mode and set the PO to 21% if using regular air? Thanks, you are all terrific!

 

[ScubaSteve]

For future reference, I find this helpful. I have it printed out as 4" x 6" photo and keep it in my logbook. This is the link to the Suunto download site....this picture is one of the last pages in the manual.

http://www.suunto.com/suunto/main/article_1column.jsp?JSESSIONID=pppJJGWYgtp3RHkfQc7XyTGpqBZKJNNBdgkh2LlyGB8JPQ4TqZqQ!-229020631!1482994954&CONTENT%3C%3Ecnt_id=10134198673939084&FOLDER%3C%3Efolder_id=9852723697223398&bmUID=h.NEm05

 

[NorthWoodsDiver]

Now that I have figure this out, (I wasn't pressing the mode button twice as StarCruiser mentioned. Now my last question. I don't see why I need to change it back and forth from air to Nitrox based on which ones I am using on a given day or week. Can't I just leave it on nitrox mode and set the PO to 21% if using regular air? Thanks, you are all terrific!

yes you can leave it on nitrox and set it at 21% however if you set it at 36%)or anything besides air) and dont dive for 24hrs it will default back to air. if you set it at 21% after the dive it will stay in nitrox mode. Thats how mine works anyway.

 

[SeahorseDeb]

Wow, you are all fantastic! Love the cat ScubaSteve. Thanks also for the link to the chart. Still wondering though if I can leave it on Nitrox mode and just adjust the PO level to 21% when I dive on regular air. I don't see why I need to change it back and forth as long as I adjust the PO level to the correct mix.

 

[SeahorseDeb]

Okay Northwoods, that is interesting that it defaults back to air if set above 21%. I just rather leave it in Nitrox and not fiddle around with it. Glad to know about accidently setting it in Gauge mode too. Oh, you are a wonderful bunch. Now, if I could just win a DUI drysuit! This hassle of only diving between april and october is driving me insane.