Uwatec AirZ O2 + Oxy2 or VR3 with SCR?

[rayzjackson]

I need a computer with an oxygen sensor to use with a Semi-Closed Rebreather (Either a Drager Dolphin or Mares Azimuth).

It seems the only choices are the Uwatec Aladin Air Z O2, or the VR3.

Can anyone offer any views on the relative merits of these two computers, or any specific experience with either of the rebreathers?

Thanks,
Ray

 

[madmole]

I've used both rebreathers and both computer set ups

There is very little in the rebreathers but the VR3 wins hands down

 

[rayzjackson]

madmole once bubbled...
the VR3 wins hands down

What sets it ahead?

I downloaded the manual and after a bit of mental gymnastics to try to figure out the order of the unnumbered pages, had a look through it.

The only computer I've used so far is the Suunto Vyper, which is no use for the rebreather as it doesn't support O2 sensors.

However one feature I assumed would be common to all computers is that it constantly displayed remaining time to NDL at the current depth and gas mix - so diving an area with several wrecks over varying depths, it was easy to watch for how long I could stay at the deeper parts and to see my time budget rise as I ascended to shallower parts.

The V3 manual is a bit cryptic without the computer to play with while reading it, but I got the impression that it displays total remaining dive time to the surface rather than time to a "must-ascend-now" limit.

Ray

 

[madmole]

It display "time to Surface" at all times and remaining no stop/stops to do

When you're on a rebreather (especially CCR), gas duration is no longer a problem (10 hours onboard!!!) so the main reason for calling a dive is when the deco gets to what you can tolerate, so Time to Surface is actually the most useful thing to know. Normally we agree, say 20 mins deco before the dive and then just swim around until thats what we've got. We did say rebreathers change the way you dive!!!! gas and cold arn't problems like they used to be

The VR3 is easy to use once you've had a play, it takes a couple of mins to sus it out and after that its easy. Every piece of info you can possibly ever want is available during the dive, but you will have to pusha a button for some of it. For example the main screen shows time to surface, and your next stop. Push the right buttom and you get a scrolling list of all stops and times

I also have a Vyper and Stinger. The Stinger sits in guage mode on my wrist as a back up bottom timer and the vyper is strapped in the Inspiration case as a third backup (in case its a really bad day) and a dive profile logger as I have the download interface for it. Plus the backup and OC bailout tables I cut before hand (VR3 will deal wirh OC bailout no probs, unlike the the Uwatec)

PS, if you get a ccr and VR3, there is one other essential that no-one mentions, you'll definately need a P valve for the drysuit