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AD_ward9 · 15th June 2008, 15:04

Quote: (Originally Posted by David Pye)

What do you get without the electronics package?

If for example someone wanted a robust rebreather with good WOB, but a Shearwater and more KISS-like electronics :-)

David

You get a rebreather with a DL P-Port (36mm internal bore), into which you can plug a cell holder or other monitor.

It is not the deliberate intent to damage other good companies with these plans, and we releasing information and samples well ahead of the main release to some other companies so they have the opportunity to do things like provide cell holders or even eCCR controllers that operate with it. For example, a unit is being provided to Narkedat90, along with engineering drawings of the relevant interfaces.

One simple interface is the converting plug to a Draeger P-Port, so existing cell holders work with it.

Answer to Richard Clark's Q:
On the second question of other scrubbers: DL has no plans to release a granular scrubber, we have not been able to get a granular scrubber through the safety case. It is EAC only. Again, this might change with third parties providing granular holders (195mm long, 125mm OD, 22mm ID, outside sealing like a dry suit cuff, if anyone wants the spec), but DL has no plans to do so. I do believe in the benefits of EACs and do not see any safety advantage from granular but do see multiple disadvantages: remember the design decisions put diver safety in prime position, rather than cost of cartridges (which is likely to reduce in any case).

Answer to Paul's Q:
The unit is within EN14143:2003 limits on WOB and breathing resistance to 55msw on air, and 300msw on Heliox. Absolutely full data is being released on these results (I have circulated some already).

However, as it is a CMF mCCR, the maximum depth is 85msw. Beyond that there is a dual scrubber version to get a 5 hour+ scrubber operating life at the EN14143 CO2 rates, (which will be 8.5 times more expensive than the single scrubber unit due to the low volume) and divers would need to wind up the Intermediate Pressure or fit an eCCR head. We did 10 dives out of the dual unit with a single set of scrubbers, and left the scrubbers out overnight once and in the unit once, without getting CO2 breakthrough. Some of those dives were quite short, others were an hour or so. The divers were big fit commercial divers working hard in series, trying to prompt CO2 breakthrough or find other O2 control limits.

The basic unit is intended to cover the entire diving needs from O.W. SCUBA to deep technical, and has features such that it can be operated safely if the diver has a complete loss of vision: silt, lights in a cave, mask etc. Beyond 85msw is so specialised, it is better to use the dual scrubber version.

Alex

15th June 2008, 15:04	#51 (permalink)
AD_ward9 RBW Member Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Jun 2005 Location: Scotland Posts: 2,014	Re: Disposable CO2 and O2 sensors Quote: (Originally Posted by David Pye) What do you get without the electronics package? If for example someone wanted a robust rebreather with good WOB, but a Shearwater and more KISS-like electronics :-) David You get a rebreather with a DL P-Port (36mm internal bore), into which you can plug a cell holder or other monitor. It is not the deliberate intent to damage other good companies with these plans, and we releasing information and samples well ahead of the main release to some other companies so they have the opportunity to do things like provide cell holders or even eCCR controllers that operate with it. For example, a unit is being provided to Narkedat90, along with engineering drawings of the relevant interfaces. One simple interface is the converting plug to a Draeger P-Port, so existing cell holders work with it. Answer to Richard Clark's Q: On the second question of other scrubbers: DL has no plans to release a granular scrubber, we have not been able to get a granular scrubber through the safety case. It is EAC only. Again, this might change with third parties providing granular holders (195mm long, 125mm OD, 22mm ID, outside sealing like a dry suit cuff, if anyone wants the spec), but DL has no plans to do so. I do believe in the benefits of EACs and do not see any safety advantage from granular but do see multiple disadvantages: remember the design decisions put diver safety in prime position, rather than cost of cartridges (which is likely to reduce in any case). Answer to Paul's Q: The unit is within EN14143:2003 limits on WOB and breathing resistance to 55msw on air, and 300msw on Heliox. Absolutely full data is being released on these results (I have circulated some already). However, as it is a CMF mCCR, the maximum depth is 85msw. Beyond that there is a dual scrubber version to get a 5 hour+ scrubber operating life at the EN14143 CO2 rates, (which will be 8.5 times more expensive than the single scrubber unit due to the low volume) and divers would need to wind up the Intermediate Pressure or fit an eCCR head. We did 10 dives out of the dual unit with a single set of scrubbers, and left the scrubbers out overnight once and in the unit once, without getting CO2 breakthrough. Some of those dives were quite short, others were an hour or so. The divers were big fit commercial divers working hard in series, trying to prompt CO2 breakthrough or find other O2 control limits. The basic unit is intended to cover the entire diving needs from O.W. SCUBA to deep technical, and has features such that it can be operated safely if the diver has a complete loss of vision: silt, lights in a cave, mask etc. Beyond 85msw is so specialised, it is better to use the dual scrubber version. Alex Last edited by AD_ward9 : 15th June 2008 at 15:09.
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