Wrist Computer: Integrated AIR or separate SPG?

[Scared Silly]

Next to pony bottles this is probably the most often discussed topic. Do a search and you will find lots posts on this.

That said I use both ... Mostly cause the transmitter was cheap and I like to be able to download my air info - so it was worth the price ;-)

 

[BKP]

That said I use both ... Mostly cause the transmitter was cheap and I like to be able to download my air info - so it was worth the price ;-)

BINGO!!

*That's* the reason I was looking for -- figuring accurate SAC time... (no... I'm not being facecious... I'm absolutely serious!)

Thanks... I knew there was a reason to I wanted to get Air-Info redundant...

 

[cobaltblue]

I use AI hoseless only. I have an SPG I could use as well but the entanglement issue is bigger than the AI failing issue. If it's not working before the dive, figure out why, repair, and dive, or not. If it freaks out during the dive, you should have a good enough idea of your air consumption to very easily get safely to the surface. You may even be able to dive a couple more minutes before surfacing, still very safely.

 

[PerroneFord]

I've not seen or heard of any that do a to-the-minute SAC calculation, just average it over time. I wouldn't pay extra for that.

My concerns with the air integrated are not so much that I might lose SPG information. I would just do the same thing I would do if my analog gauge failed. Thumb the dive. Either you calculated properly and you have plenty to get home, or you miscalculated and you're screwed.

My concern is that if your battery dies, or some other malady hits your computer, you've lost EVERYTHING. SPG, Depth, dive time, everything. I prefer not to put all my eggs in one basket so to speak.

Others seem ok with it. Personal choice.

-P

BINGO!!

*That's* the reason I was looking for -- figuring accurate SAC time... (no... I'm not being facecious... I'm absolutely serious!)

Thanks... I knew there was a reason to I wanted to get Air-Info redundant...

 

[Divingguy]

I had the VersaPro, with a full console. When I then went with the hoseless AI VT Pro, I just kept the console for "backup". However, the VT Pro has never failed me. I will say that it does give you a warning for both the transmitter and receiver batteries, so short of a freak flooding, most likely caused by having messed with the case, unexpected failure should be rare. I am a backup kind of guy, but do have full confidence in both of my wrist units.

 

[Scared Silly]

I've not seen or heard of any that do a to-the-minute SAC calculation, just average it over time. I wouldn't pay extra for that.

My concerns with the air integrated are not so much that I might lose SPG information. I would just do the same thing I would do if my analog gauge failed. Thumb the dive. Either you calculated properly and you have plenty to get home, or you miscalculated and you're screwed.

My concern is that if your battery dies, or some other malady hits your computer, you've lost EVERYTHING. SPG, Depth, dive time, everything. I prefer not to put all my eggs in one basket so to speak.

Others seem ok with it. Personal choice.

-P

This is true ... Suunto's Dive Manager uses an average depth. However, the info is there. I am using DiveLog for Macs and I am not sure what Mark does, running average or total average. I need to check with him. That said I just like the fact that I get the starting/ending PSI and SAC rates in my log book. Yes I am too lazy to remember to do it after each dive.

And you are correct about all the eggs in one basket. Which is why I have a back up on my other wrist. Anymore it is pretty hard to find any type of watch that does not have a battery. And there is a lot to be said about not using a computer at all.

 

[Bowtie22]

Always prepare for the "what if" and you should always be "reasonably" safe. Still a matter of oppinion and personal prefence. I prefer redundadnt systems whenever my life is dependant on it. I have never had to depend on my SPG because my computer is always right. But after all it is a computer and it was made my man so there is always a chance that !@#$ happens. I have to be redundant because if something can happen it usually happens to me.:biggrin2:

Now with all of that being said if there was ever an event that the computer or the SPG went out it would probably be the smartest decision to abort the dive hit the safety stop and find out what went wrong on the surface. Either way you do it is up to you but it is ALWAYS a good idea to know your air consumption rate for the depth you are diving and compare it to your AI, SPG or both combined to make sure that everything is consistant with each other and consistant with what you think it should be.

So there is your answer....There is no correct answer.... just remember to dive what you feel comfortable with and always dive safe.

 

[OE2X]

Here is my experience:

Used to use an AI computer - now it's a backup and sits in my dive box.

Use a computer - wrist mounted - as a bottom timer.

Use an SPG - as backup to my brain.

When you know what your SAC is for most of your dives and you have enough bottom time, you should be able to know at any point during the dive how much gas you have consumed. If you dive with a regular buddy you will know his/hers without looking as well.

I always guess my gas use before I look at my SPG. What this typically means is that I don't look at my SPG more than 3 times during the course of a dive. The only reason I even look at it, is because of force of habit. I find that I'm within 100 psi any time I check. Since it is extremely rare that I go below 1000 psi on a steel 130 then 100 psi isn't going to matter at all.

When do I check more frequently?
Air shares
Increase in work load
A dive that lasts longer than 90 minutes.

 

[Charlie59]

use AI alone, shouldn't you?

 

[melle]

I use wrist mounted AI, but I have a hose mounted SPG available, in case my computer ****s the bed.
Then again, I usually dive with two computers, or a computer and a watch... I love using computers. Then again, I am a nerd.

I have a Suunto Vytec with transmitter and I never had a problem with it (knock knock). Non AI: Seemann Sub XP5 (=Oceanic) is good. So is a Stinger.

It is a matter of personal preference. For me, personally, I feel save being able to read an analog instrument in case of a failing piece of equipment.

Melle