CNS% ?

[Vortax]

I have also notice this issue.

OSTC 2N gives you a (very) lower CNS% calculations when you plan your dive directely from 2N.

As an example: 60m x 31min, tx18/40, EAN50 and O2 100%. GF 20 low, 85 high.

Decoplanner gives me CNS% 60%

OSTC 2N gives me CNS% 22% !!!!!!

It's a HUGE gap between both softwares. Are we facing a bug?

By the way, firmware 2.21 on my OSTC.

[Vortaz]

By the way, I tried planning one dive a made the other day, at 60mx20 min

divelog of OSTC 2n gives me CNS% 31% (that was an actual dive)

Decoplanner calculates me CNS% 33% (fairly close to the atual CNS registered by OSTC 2N)

But if I plan the same dive, I am given CNS% 15%

I am pretty sure that OSTC 2N calculates right your CNS% in an ACTUAL dive, but the planner included has some kind of bug that prevents a right calculation of CNS%

cheers.

[Smiler1968]

Vortaz Wrote:
-------------------------------------------------------
> By the way, I tried planning one dive a made the
> other day, at 60mx20 min
>
> divelog of OSTC 2n gives me CNS% 31% (that was an
> actual dive)
>
> Decoplanner calculates me CNS% 33% (fairly close
> to the atual CNS registered by OSTC 2N)
>
> But if I plan the same dive, I am given CNS% 15%
>
> I am pretty sure that OSTC 2N calculates right
> your CNS% in an ACTUAL dive, but the planner
> included has some kind of bug that prevents a
> right calculation of CNS%
>
> cheers.



Thanks, that's what I've been saying.

Regards

Jerry

[JeanDo]

Hello,

Here is what I get from OSTC Planner :
[quote="Bühlmann ZH-L16C-1a 2002 with GRADIENT FACTOR decompression:
* GF_low (CF32) = 20 %
* GF_high (CF33) = 85 %
* deco offset (CF16) = 1.0 m
* last stop (CF29) = 3 m
* dive started at Pamb = 1013 mbar
Gas#1 = 18/40 at 0 m
Gas#2 = 50/0 at 21 m
Gas#3 = 100/0 at 6 m
Gas switch delay (CF55) = 0 min

0:00 60.0m DESCENT DONE
...
31:08 60.0m Deco:
36 m : 1 ' 35 '
33 m : 1 ' 36 '
30 m : 2 ' 38 '
27 m : 3 ' 41 '
24 m : 3 ' 45 '
21 m : 2 ' 47 ' (SWITCH Gas#1 -> Gas#2)
18 m : 3 ' 50 '
15 m : 4 ' 55 '
12 m : 6 ' 61 '
9 m : 9 ' 70 '
6 m : 10 ' 81 ' (SWITCH Gas#2 -> Gas#3)
3 m : 21 ' 102 '
0 m : --- ' 103 '
TTS = 72 '
CNS = 67%"]
[/quote]

I do have the same results with my OSTC.2n ... Do you see any difference with what you did program ?
Are you sure you set the switch depth ?

Regards,

[Vortax]

I'll try again when I arrive home, but last time I did this planification, OTSC 2N gave me 22%

OSTC Planner (Pc-Mac software) gives you correct CNS%.

I'll report tomorrow.

[Vortax]

Ok, re-planned the dive with my OSTC 2N. 60mx31min
Tx18/40 first gas yes, change 0m
EAN50 change 21m
O2 change 6m

Decompression model OC GF 20 low, 85 high.
All the others CF the same way JeanDo said.

36m: 1'
33m: 2'
30m: 2'
27m: 3'
24m: 3'
21m: 3' (switch is not indicated on OSTC, but assumed)
18m: 3'
15m: 4'
12m: 7'
9m: 9'
6m: 11'
3m: 21'

TTS: 75'
CNS%: 0% --> 22%

Gas usage (CAS 20 l/min both dive and deco):
G1: Tx 18/40: 5646
G2 EAN50: 1217
G3 O2: 915


As you can see, everything OSTC give me is similar to OSTC planner (Pc-Mac software), except for CNS%, wich is clearly lower.

If needed, I can take photos...

By the way... Installed stable 2.21 firmware, SPANISH version.

[Vortax]

Well, installed firmware 2.50 on my OSTC 2N.

CNS% calculation on the planner included in OSTC 2N is now working OK. Bug Solved.

Thanks!!!