I think I may be ate up with this....

[tstormdiver]

No. On the Prism2 The Predator (Petrel on the newer models) is hardwaired into the electronic head.

 

[BoltSnap]

No. On the Prism2 The Predator (Petrel on the newer models) is hardwaired into the electronic head.

And a computer that isn't hardwired to the ccr can't be used to keep track of deco and NDL status while using a ccr?

 

[tstormdiver]

And a computer that isn't hardwired to the ccr can't be used to keep track of deco and NDL status while using a ccr?

Let me back up,.. I forgot, the Petrel on the newer models (Can Bus) can be removed from the head,... however, the older models like mine, it can not. I could dive a secondary Shearwater computer with the same algorithm, & it would read fairly close to what the hard wired computer says, but not exact, as the PO2's on the controller do change with changes in depth, until the machine catches up to the set point PO2... The non connected computer just assumes a steady PO2, so there would be some difference.

 

[oly5050user]

Let me back up,.. I forgot, the Petrel on the newer models (Can Bus) can be removed from the heads dive ,... however, the older models like mine, it can not. I could dive a secondary Shearwater computer with the same algorithm, & it would read fairly close to what the hard wired computer says, but not exact, as the PO2's on the controller do change with changes in depth, until the machine catches up to the set point PO2... The non connected computer just assumes a steady PO2, so there would be some difference.

not a rb diver here , but would not wearing a simple backup computer set to 21% not work and be conservative enough so that if you need to switch to OC you could? Then you can continue a dive day , you could even continue to use nitrox if you like. Your O2 exposure time may be a bit off,but by keeping time of dive should be managable.

 

[hroark2112]

That's a decent idea, however some RB dives would likely lock out your "backup" computer when it thinks you're blowing your NDL. Hopefully you can turn off all the beeping too.

one day I'll find a relatively inexpensive backup computer that I can set for RB diving.

 

[tstormdiver]

That's a decent idea, however some RB dives would likely lock out your "backup" computer when it thinks you're blowing your NDL. Hopefully you can turn off all the beeping too.

one day I'll find a relatively inexpensive backup computer that I can set for RB diving.

Thank goodness the Shearwaters do not "beep" (or lock you out for that matter). I Just sold a Petrel with a Fischer connector. I was going to have it hooked up to my rebreather as a back up monitor, but then decided that I am going to upgrade to the newer electronics. The new electronics are digital, whereas the older models are analog & the Petrel I had was analog & would not work with the newer electronics. As quickly as the Petrel sold,... I must not have asked for enough it...

 

[rongoodman]

Can you switch to an oc setup for your second dive after making your first dive with a ccr (for any reason you can't use the ccr after the first dive)? How would you handle the NDL and whole deco part if you do?

Even though my back-up Petrel wouldn't be following the set-point on the Prism exactly, I don't see how it would be that far off. For the second dive. I'd just switch it to OC and go diving. If anything, I would expect the back-up to be the more conservative of the two, since it wouldn't know if I decided to bump up the set-point manually for whatever reason. It would be no different than depending on the back-up to manage the deco on a bail-out should the primary computer or electronics fail.

 

[hroark2112]

I'm considering a NERD. I want one a lot!!! Then I can make my Petrel the backup, although I'd prefer to continue to Fischer cable it and maybe hard-wire the NERD.

 

[Dr. Lecter]

And a computer that isn't hardwired to the ccr can't be used to keep track of deco and NDL status while using a ccr?

If you're diving with a stand alone or fisher connected backup, you could take it with you in OC mode no problem. Great reason to never just dive the onboard deco computer by itself.

When I finally ditch my rEvo II for a shiny new Expedition, I'm looking at hardwired NERD (3 cells deco) and Petrel (3 cells controller) for the unit itself, but I think I'll keep the SA Petrel just for this kind of issue.

 

[rongoodman]

If I am diving my local quarry (1-1/2 hrs away) I will typically take my doubles & neccesary set- up if my rebreather goes down. I have a large full sized pick- up, so plenty of room. When I go to Bonaire in July, I will be taking a travel BC & OC regulator, so that I won't have to miss too much diving if things go sideways.

I'd just take a single tank wing, STA, and a couple of hoses and extra second stage to switch my bail-out regulator over. What shop will you be diving with?