Unrealistic D4i Novo NDL

[Centrals]

RGBM does not take kindly on reserved profile.

 

[Drashka]

OK so I Just logged the dives in DM5, nothing weird in the profile (no fast as cent time or whatever) Just the common tissue level warning when surfacing. So I really don't know. Only difference between our settings is that my deep stop is activated and her is not, might be this ? From what you explained i really don't understand because i double checked everything and it doesn't explain this ultra conservatism. So we're thinking about servicing but that's weird because the computer is quite New (september 2018).

 

[JohnnyC]

Suunto's have two different conservatism settings, "altitude" and "personal." You've said no altitude settings, but have you checked the "PO, P1, P2, etc" settings as well?

That coupled with things like jigsaw profiles, fast ascent rates, short SI's, etc. will torch your NDL for a repetitive dive.

Your PO2 setting is just for an alarm (it functions the same way as the max depth alarm). It beeps if you hit your MOD. It doesn't affect the NDL calculations.

Get a better logging software, Subsurface or similar, MacDive is good if you're on a Mac. DM5 sucks.

 

[dmaziuk]

Suunto's have two different conservatism settings, "altitude" and "personal." You've said no altitude settings, but have you checked the "PO, P1, P2, etc" settings as well?

Those should've affected the first dive as well, although the difference on the first dive may be small enough to get overlooked. OTOH I once ran into a couple with maxed out "personal" conservatism on their gekkos and they had a non-optional safety stop on dive 1 of the day (if not trip)...

 

[Drashka]

P0/No fast ascent/no jigsaw. I really don't know why. Surf interval was one lovely hour. I'll try to relog them on subsurface through, didn't know the software. But in the end seems like something wrong with the computer (better on conservatism side than opposite but still !)

 

[JohnnyC]

If something is wrong with the computer, it doesn't matter if it's on the conservative side. An unknown failure state is a liability!!! Hope you get it sorted out!

 

[CandiveOz]

@Drashka If all three of you are diving together with 3 Sunnto D4i's its reasonable to assume your NDL's should approximately be the same as you have stated in your original post. Therefore, compare dive plans on each computer. If one is out, compare settings on each computer.

 

[scubadada]

@Drashka If all three of you are diving together with 3 Sunnto D4i's its reasonable to assume your NDL's should approximately be the same as you have stated in your original post. Therefore, compare dive plans on each computer. If one is out, compare settings on each computer.
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Good idea. When my pressure sensor went bad on an old Oceanic Pro Plus, it would give shorter NDLs in the planner when all other settings were identical. I was assuming you already made sure the computers are on the same nitrox mix, same personal adjustment, and same altitude setting.

 

[dmaziuk]

Good idea. When my pressure sensor went bad on an old Oceanic Pro Plus, it would give shorter NDLs in the planner when all other settings were identical.

I am having real difficulty imagining how that would actually work... Unless you're talking immediately after a dive, when there's still (incorrect) residual loading.

 

[scubadada]

I am having real difficulty imagining how that would actually work... Unless you're talking immediately after a dive, when there's still (incorrect) residual loading.

You have no imagination. If the pressure sensor is faulty, i.e., is registering a faulty pressure/elevation, it will give faulty NDL with planning all of the time, consistently.