Atomic Cobalt - Does It Have A Gauge Mode?

[Phil_C]

As the title says - I am trying to find out if the Cobalt has a gauge mode, perhaps I am missing it but I can't see an option to set it just to gauge.

There does not appear to be anything about a gauge mode in the manual either.

Can anyone help?

Phil

 

[RonR]

No, there isn't a gauge mode on the Cobalt. Out of curiosity, what is your reason for wanting a gauge mode on the console? Is it for diving with another computer or tables, with trimix, or something else? And if you had a gauge mode, what information would you prefer to still see displayed, apart from depth and time?

-Ron

 

[Phil_C]

Hi Ron,

Thanks for responding - and nice to know I'm not going mad then

Ok, short summary/answer I hope - I mostly dive my Cobalt when I am abroad with my warm water rig, which is single tank diving, normally no deco, or just a short deco commitment and either air, or a standard nitrox (32 or 36) mix.

When at home I am usually diving cold water in either side mount or twinset.

With side mount I don't use the Cobalt, just two spg's and a competitors wrist mounted stand alone (Petrel).

With the twinset I bought a second connector for the Cobalt some time ago and started to use it on my twin set, connected on the primary reg side. Again air or 32/36 as standard.

I have recently started doing accelerated decompression type dives with the twin set and a stage and either 50% or 80% as the final deco gas. We have been using tables or software to calculate the deco stops etc.

On a couple of dives on Sunday I also programmed the mixes into the Cobalt and set switch alerts, but noticed that these did not match the run times and stops from the dive plan. (I haven't played around with settings, so might be able to match profiles better if I did).

I used the Petrel in Gauge mode as a depth and bottom timer, and used the stop watch function to time the deco stops after the gas switches.

I am just a bit concerned that if the Cobalt gave a much more conservative profile than the tabled/calculated dive plan I could end up getting a deco violation on the Cobalt, and risk locking it out by following the dive plan.

In any event I would like to be able to use it as a depth gauge/stopwatch/timer and if needed as redundancy for the Petrel.

So the reason I started looking for gauge mode was that I had thought to switch it to gauge mode, using it as a depth gauge/bottom timer, and backup stopwatch for deco stops if needed.

So I guess what I was looking for and hoping I would find was :-

• Depth
• Dive timer
• An easily accessible and activated stopwatch function
• Gas pressure, gas time remaining etc. (the current gas information/features).
• Dive profile/gas usage logging.
• The reassurance that following my tables will not inadvertently lock me out of the Cobalt.

I haven't ever managed to upset the Cobalt before, out of 200 plus dives I think I have had a fast ascent rate warning once or twice but that was about it, so to be honest I am not sure what happens if it thinks you have blown off a deco stop/obligation, but underwater part way through a deco dive would not be the time to find out I no longer had a redundant timer/depth gauge etc.

Cheers

Phil.

 

[RonR]

Phil, thanks for that detailed explanation, it helps to hear how people are using (or want to use) the products.

I can provide one reassurance- the Cobalt will NOT lock you out, no matter what you do. If your dive plan/ profile causes the Cobalt to violate it’s algorithm, it will give you a deco violation warning, tell you the schedule might not be verified, and for the next 24 hours it will present a warning screen to you before it enters dive mode. But it will continue to calculate- based on what you did- a best fit profile for the algorithm, and you can otherwise continue to use it normally. We leave it to the diver to determine if their violation was relatively trivial (or as in your potential case, caused by following another schedule or computer), and can be ignored.

What triggers a violation warning in the Cobalt is not a fixed time or distance away from a stop, but is algorithmically determined based on the schedule, the depth of the stop, and the distance and time shallower than the stop. When we have people diving the Cobalt with other computers (particularly Buhlmann based like the Petrel), what we see most often is a difference in the distribution of stops. The Cobalt will often, particularly on deeper dives, call for a first stop deeper than the other computer’s first stop, and blowing through that will result in a violation. But the Cobalt will just recalculate a revised schedule and add time to shallower stops- and show a warning.

On a couple of dives on Sunday I also programmed the mixes into the Cobalt and set switch alerts, but noticed that these did not match the run times and stops from the dive plan. (I haven't played around with settings, so might be able to match profiles better if I did).

It’s not clear to me when you talk about the Cobalt’s schedule not matching the dive plan if you are referring to other dive planning software or the Cobalt’s internal planner. The Cobalt’s planner is designed to give an exact match to what it would deliver in actual diving, including taking into account your current saturation, the surface ambient pressure, and any additional surface interval you enter. You can simulate any gas switches (obviously EAN only). And you can use it to generate schedules you can view (the “Show Deco” button in the planner) and record separately for manual backup. The Cobalt would be able to calculate the dives you are describing with a 50% or 80% O2 final deco mix, unless you are using trimix on the dive. The Cobalt’s planner is basically designed to replicate the functions of desktop planning software, but using actual data for your prior saturation. Using the Cobalt’s simulator would also give you a way to compare the profiles it generates at various settings / conservatism vs. other computers or software.

Hope this helps, and thanks for the input. We are looking at various options for data display in gauge mode on our wrist computer.

-Ron

 

[Phil_C]

Hi Ron,

As always many thanks for taking the time to respond.

It is good to know the Cobalt doesn't lock out, I didn't think it did.

When I said the Cobalt did not match the dive plan, I mean it did not match the table generated dive plan we were using, which was based on the BSAC OXSTOP tables.

The BSAC tables as I understand it are written by Dr. Tom Hennessy and are a bespoke table set based on algorithms written exclusively for BSAC. I don't think they particularly closely follow the Bulhmann or any other algorithm, but obviously do produce similar no-stop times and so on.

In time I will go over to using one of the computers to produce a more accurate dive profile and deco schedule 'on the fly', but at the moment I have only just finished the course so am still using the tables and dive planning process they taught to make sure gas planning, run times and so on are properly controlled.

Best

Phil