Suunto Stinger problem with Nitrox

Hi Guys

I recently dived a 40M wreck with a mix of 31%. I carefully set my stinger
to 31% and got my buddy to verify the setting. As usual jumped in and except
for cursory checks largely ignored my computer for the first part of the
dive. About 15 mins in I noticed that the computer was still in EAN mode,
but was calculating a mix of 21%- Not catistrofic in the context.... but
more than a little worrying... (incidentally it still retained the 1.6Bar
PPO2 set point) and I spent an extra 20 mins on the line.

Has anyone had similar maladies ? or know why this would happen
(I know I was running pretty close to MOD @ 1.6 Bar set point)

Also
After the dive and a couple hours SI the computer would not exit EAN mode to
go back to Air for the 2nd dive (so used 21% obviously) is this normal ?

Thirdly

When I went to hook up to SDM on the computer I got missing dives warning in
the sequence and it ended up with a dive profile for a couple of hours at
96M (which obviously impresses the novices at the club)

When tried upload next day again everythings seems normal.....



WTF ???? any ideas ?



--
pat rick at vir gin dot net

www.tigershark.org.uk

PC wrote:

> After the dive and a couple hours SI the computer would not exit EAN mode to
> go back to Air for the 2nd dive (so used 21% obviously) is this normal ?

I don't have a stinger, but when my partner was buying her computer the
shop assistant pointed out this "feature" of the suunto computers. They
will not allow you to change from air->nitrox or back again until the
computer is desaturated.

You dive nitrox, so I guess the answer is to keep in nitrox mode and
just set 21% when you dive air. I think the logic behind having a
seperate air and nitrox setting is good, as it means that someone who
doesn't have any knowledge of nitrox isn't going to change the mix by
accident, but I don't really understand why the computer can't swop the
tissue sats between settings.

HTH,

Ben

--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Ben Panter, Edinburgh, UK
email is false. Use my name (no spaces) at bigfoot which is a com.

PC wrote:
> Hi Guys
>
> I recently dived a 40M wreck with a mix of 31%. I carefully set my stinger
> to 31% and got my buddy to verify the setting. As usual jumped in and except
> for cursory checks largely ignored my computer for the first part of the
> dive. About 15 mins in I noticed that the computer was still in EAN mode,
> but was calculating a mix of 21%- Not catistrofic in the context.... but
> more than a little worrying... (incidentally it still retained the 1.6Bar
> PPO2 set point) and I spent an extra 20 mins on the line.

I don't know if the Stinger is the same as earlier Suunto's, but my
old Solution Alpha used to revert to 21% if you did not dive within
an hour of setting it.

- Keith

"PC" wrote

> I recently dived a 40M wreck with a mix of 31%. I carefully set my stinger
> to 31% and got my buddy to verify the setting. As usual jumped in and
except
> for cursory checks largely ignored my computer for the first part of the
> dive. About 15 mins in I noticed that the computer was still in EAN mode,
> but was calculating a mix of 21%- Not catistrofic in the context.... but
> more than a little worrying... (incidentally it still retained the 1.6Bar
> PPO2 set point) and I spent an extra 20 mins on the line.
>
> Has anyone had similar maladies ? or know why this would happen
> (I know I was running pretty close to MOD @ 1.6 Bar set point)

I've not heard anyone complain about this particular problem, but several
have commented on the overly conservative way the Suunto computers handle
nitrox, particularly at 1.6 bar. It seems Suunto believes 1.4 is the max
you should consider and penalizes you for chosing otherwise. These issues
have been posted here and elsewhere, in several discussions. A little
research may convince you to exchange your Suunto for another brand. It was
sufficient to keep me from buying one in the first place.

> Also, After the dive and a couple hours SI the computer would not exit EAN
mode to
> go back to Air for the 2nd dive (so used 21% obviously) is this normal ?

I'm not sure normal is the right word, but it is common. There's a rational
basis for this that, once you use an oxygen enriched mix, monitoring oxygen
levels is an issue and continues to be one for a relatively long time. Most
nitrox computers report oxygen levels only in nitrox mode (true of my
Oceanic and Genesis computers). They won't allow you to use the air setting
until they compute your O2 levels have returned to normal surface
saturation.

My computers are more annoying that that. If I dive nitrox, I have to reset
the computer for subsequent dives, even if I use the same nitrox mix.
Otherwise, they set themselves to 50% Oxygen and 79% nitrogen, ie, the most
conservative levels for each gas they are able to handle. Trust me, one
dive with your computer set this way will really mess up your time available
for that, and later dives in a multi dive sequence.

> When I went to hook up to SDM on the computer I got missing dives warning
in
> the sequence and it ended up with a dive profile for a couple of hours at
> 96M (which obviously impresses the novices at the club)
> When tried upload next day again everythings seems normal.....
> WTF ???? any ideas ?

Two:
1. If you can, return the Suunto and get a computer that's a little more
realistic regarding how it handles nitrox.
2. Talk to the manufacturer. The problems you are having do not sound
normal.

Lee

> > When I went to hook up to SDM on the computer I got missing dives
warning
> in
> > the sequence and it ended up with a dive profile for a couple of hours
at
> > 96M (which obviously impresses the novices at the club)
> > When tried upload next day again everythings seems normal.....
> > WTF ???? any ideas ?
>
> Two:
> 1. If you can, return the Suunto and get a computer that's a little more
> realistic regarding how it handles nitrox.
> 2. Talk to the manufacturer. The problems you are having do not sound
> normal.
>
> Lee
>
I've had the Solution Nitrox, Vyper and now Vytec. The Vyper & Vytec dont
revert back to 21% they keep the last setting.

They are adjustable from 1.4 to 1.6, but I only use 1.6 for a deco gas.

In message <eeiYc.225$Up6.63@newsfe6-gui.ntli.net>, PC <w@w.W> writes
>I recently dived a 40M wreck with a mix of 31%. I carefully set my
>stinger to 31% and got my buddy to verify the setting. As usual jumped
>in and except for cursory checks largely ignored my computer for the
>first part of the dive. About 15 mins in I noticed that the computer
>was still in EAN mode, but was calculating a mix of 21%- Not
>catistrofic in the context.... but more than a little worrying...
>(incidentally it still retained the 1.6Bar PPO2 set point) and I spent
>an extra 20 mins on the line.
>
>Has anyone had similar maladies ? or know why this would happen (I know
>I was running pretty close to MOD @ 1.6 Bar set point)

At 31% O2 and 1.6pp, my mosquito allows a depth of 40.4m. I dont know
what it does if you exceed the depth, but it is possible that it does
something strange. Is it possible that you exceeded 40.4m?

--
Richard Faulkner

On Sun, 29 Aug 2004 12:58:28 +0000 (UTC), "TonyH"
<tony@samesamediving.com> wrote:

>> > When I went to hook up to SDM on the computer I got missing dives
>warning
>> in
>> > the sequence and it ended up with a dive profile for a couple of hours
>at
>> > 96M (which obviously impresses the novices at the club)
>> > When tried upload next day again everythings seems normal.....
>> > WTF ???? any ideas ?
>>
>> Two:
>> 1. If you can, return the Suunto and get a computer that's a little more
>> realistic regarding how it handles nitrox.
>> 2. Talk to the manufacturer. The problems you are having do not sound
>> normal.
>>
>> Lee
>>
>I've had the Solution Nitrox, Vyper and now Vytec. The Vyper & Vytec dont
>revert back to 21% they keep the last setting.
>
>They are adjustable from 1.4 to 1.6, but I only use 1.6 for a deco gas.

No idea about the Vytec but the ppO2 setting on the Stinger and Vyper
(and Cobra) only controls an alarm. The computer will behave the same
regardless of this setting - i.e. it will use NOAA parameters for O2
exposure up to a ppO2 of 1.4 and for higher ppO2 it will go all spazzy
and tell you that you are in imminent danger of an O2 hit.


Laz

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A foolproof method for sculpting an Elephant:
First, get a huge block of marble. Then, chip away
everything that doesn't look like an Elephant.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Change "nospam" to "ntlworld" to reply.

Yes I did exceed the MOD. But surely this isn't going to change the mix on
the computer?




"Richard Faulkner" <richard@estate.demon.co.uk> wrote in message
news:$m70xcS35dMBFwqR@estate.demon.co.uk...
> In message <eeiYc.225$Up6.63@newsfe6-gui.ntli.net>, PC <w@w.W> writes
> >I recently dived a 40M wreck with a mix of 31%. I carefully set my
> >stinger to 31% and got my buddy to verify the setting. As usual jumped
> >in and except for cursory checks largely ignored my computer for the
> >first part of the dive. About 15 mins in I noticed that the computer
> >was still in EAN mode, but was calculating a mix of 21%- Not
> >catistrofic in the context.... but more than a little worrying...
> >(incidentally it still retained the 1.6Bar PPO2 set point) and I spent
> >an extra 20 mins on the line.
> >
> >Has anyone had similar maladies ? or know why this would happen (I know
> >I was running pretty close to MOD @ 1.6 Bar set point)
>
> At 31% O2 and 1.6pp, my mosquito allows a depth of 40.4m. I dont know
> what it does if you exceed the depth, but it is possible that it does
> something strange. Is it possible that you exceeded 40.4m?
>
> --
> Richard Faulkner

update:

to test I put the computer into EAN at a rich mix...
I went into dive mode just over an hour later, and guess what - it had
reverted to 21%
(thanks Keith) this is not what I would call a good feature, (being in IT a
golden rule is the system leaves the set parameters as are unless it
explicity informs the user and asks for approval) but then again I'm not a
hyperbaric specialist.

Can someone please try this on their model so I know if
Suunto revert to 21% after an hour as a 'safety feature'
My stinger is fupped

Thanks for the earlier post on the revert to air it makes sense....although
fairly academic from suunto as its hardly going to save from cumulative O2
exposure (and if it were to save from an O2 hit past MOD- why bother having
an Air mode at all ???) (thanks Lee & others)

Also I suppose it is possible that the 'download process just happened to
get corrupted that once...


who says lightening dosent strike the same place thrice ?

thanks


P




"PC" <w@w.W> wrote in message news:eeiYc.225$Up6.63@newsfe6-gui.ntli.net...
> Hi Guys
>
> I recently dived a 40M wreck with a mix of 31%. I carefully set my stinger
> to 31% and got my buddy to verify the setting. As usual jumped in and
except
> for cursory checks largely ignored my computer for the first part of the
> dive. About 15 mins in I noticed that the computer was still in EAN mode,
> but was calculating a mix of 21%- Not catistrofic in the context.... but
> more than a little worrying... (incidentally it still retained the 1.6Bar
> PPO2 set point) and I spent an extra 20 mins on the line.
>
> Has anyone had similar maladies ? or know why this would happen
> (I know I was running pretty close to MOD @ 1.6 Bar set point)
>
> Also
> After the dive and a couple hours SI the computer would not exit EAN mode
to
> go back to Air for the 2nd dive (so used 21% obviously) is this normal ?
>
> Thirdly
>
> When I went to hook up to SDM on the computer I got missing dives warning
in
> the sequence and it ended up with a dive profile for a couple of hours at
> 96M (which obviously impresses the novices at the club)
>
> When tried upload next day again everythings seems normal.....
>
>
>
> WTF ???? any ideas ?
>
>
>
> --
> pat rick at vir gin dot net
>
> www.tigershark.org.uk
>
>
>

On Tue, 31 Aug 2004 10:13:51 GMT in uk.rec.scuba, PC says:

>"PC" <w@w.W> wrote in message news:eeiYc.225$Up6.63@newsfe6-gui.ntli.net...
>> Hi Guys
>>
>> I recently dived a 40M wreck with a mix of 31%. I carefully set my stinger
>> to 31% and got my buddy to verify the setting. As usual jumped in and
>except
>> for cursory checks largely ignored my computer for the first part of the
>> dive. About 15 mins in I noticed that the computer was still in EAN mode,
>> but was calculating a mix of 21%-
>>
>>>update:
>
>to test I put the computer into EAN at a rich mix...
>I went into dive mode just over an hour later, and guess what - it had
>reverted to 21%

I have a Vyper and IIRC that reverts to 21% after 2 hours unless there
is still no fly time showing. Last year I dived a series of dives with
a colleague, pretty much all of them on Nitrox. We both were using
Vypers, he had a few minutes less no fly than me and on one dive
between checking on the boat and entering the water (5 minutes) his
Vyper reverted to 21%[1]. I entered the water still with a few minutes
of no fly time from previous dives and my Vyper retained the Nitrox
setting from kitting up earlier.

[1] This became apparent when so that we could dive later that day
there was an extra few minutes of stops so as not to bend his Vyper.

--
Ian
"Democracy, what we need - Kakistocracy what we've got"