Unbalance SCR regs

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@ batman

what you don't want to understand is, even with your trimix of 12% o2, if you feed more oxygen into your system then you burn in your body, partial pressure will raise steadely. if it gets to high, you have to stay in your limits with cns and further if it goes above your desired limit (ppo2) you have to vent your system. exhaling through your nose. so you want to switch to your bail-out or do the dive on oc from the beginning.

do you realize know, that with a compensated first stage your o2 situation gets worse with each breath you take. it makes no sense to use a scr at such depths.

all clear know?

its 0045 hours now, i go to bed. hope you don't do this dive today. cu
swisstrav
 
padiscubapro:
Also the IP of a drager is 450psi it will work in the sonic range at 300fsw, the no compensated regs on a kiss first of all act like restricted orifices not sonic and they are based on standard 1st stages with the pressure port blocked, thats why they stop at around 300 fsw - when set at 135psi (150 psia) the pressure at 300 psw is about 148 psia

The IP on the Dolphin is 245psi (16.7 bar) that's from tab 3, page 3 of the tech service manual. The hoses are rated at 27.5 bar (400psi). Where does the 450psi come from?
On the original question, a 60 % jet flows 5.7 liters/min. You put a 120cf tank on and you have 10 hours of flow, roughly. Because of depth issues and other inconsistancies with the system including the diver, You would need oxygen, a travel mix from surface to rebreather depth(can't breath mix at surface), a bailout deco set from max depth going up. A computer generated program would only give you a rough idea of what to expect. you would need to do bounce dives to see the real time numbers(ppo's). An unbalance reg will take you only so far, you would have to have a manual feed connection to the loop that was connected to a compensated, seperate reg to supply oxygen at deeper depths. Would probably have to be a mix so the O2 didn't spike.
One application I've seen pictures of was, to carry a second semiclosed rebreather as bailout( like the joker) to reduce the load. Complicated.
Padiscubapro- when you are doing the deep trimix rebreather dives, how much bailout do you carry. I ask because it sounds like you already do the dives he is asking about.
 
swisstrav:
@ superman thats what you are. thanks for the addr. in bonaire.

if it works out, will be there with my 2 boys during easter vacation. (12+15 need to do their advanced.

nice day swisstrav

My kids loved Caren Eckrich, a marine biologist on Bonaire for guided dives and "discovery" check her out at: http://www.bonairenature.com/seandiscover/
 
Superman:
My kids loved Caren Eckrich, a marine biologist on Bonaire for guided dives and "discovery" check her out at: http://www.bonairenature.com/seandiscover/

superman

many thanks for your tip. although english is mutch more emphazised as french, it wil be quite a task to communicate in english.

however trowing them into the deep water in therms of english is not a bad thing i guess.

if we make it to bonaire i will get in touch with caren.

tks for your info and have a nice week end
swisstrav
 
deepblueh2o:
The IP on the Dolphin is 245psi (16.7 bar) that's from tab 3, page 3 of the tech service manual. The hoses are rated at 27.5 bar (400psi). Where does the 450psi come from?
On the original question, a 60 % jet flows 5.7 liters/min. You put a 120cf tank on and you have 10 hours of flow, roughly. Because of depth issues and other inconsistancies with the system including the diver, You would need oxygen, a travel mix from surface to rebreather depth(can't breath mix at surface), a bailout deco set from max depth going up. A computer generated program would only give you a rough idea of what to expect. you would need to do bounce dives to see the real time numbers(ppo's). An unbalance reg will take you only so far, you would have to have a manual feed connection to the loop that was connected to a compensated, seperate reg to supply oxygen at deeper depths. Would probably have to be a mix so the O2 didn't spike.
One application I've seen pictures of was, to carry a second semiclosed rebreather as bailout( like the joker) to reduce the load. Complicated.
Padiscubapro- when you are doing the deep trimix rebreather dives, how much bailout do you carry. I ask because it sounds like you already do the dives he is asking about.
Dives like that are planned as a team... We plan enough gas to get 1.5 divers out of trouble..

I usually have the students slinging 2x40's, and for good measure I'll sling 2x80(since I am very confortable with them, and rather make it a bit easier on the students) and have 100% oxygen staged shallow... These are just general guidlines.. each dive is planned based on logistics.. If I'm going down a fixed line its not uncommon to stage bottles at key oints on the line. also I usually pre arrange specific signals to tell the surface support there might be an issue, and we may need gas... Every dive has its own problems and solutions.
I'll be doing some dives in the near future that will require the entire team (3-5 man teams)to carry 80s as bailouts with safety dives also with gas available..

if I am doing with a bunch of experienced divers.. we will truely plan the 1.5x required.


Its been about 2 years (maybe 3) since I played with any of the drager's, so my memeory may be a little clouded, sometime all the specs get blended together... I know the Ray and Dolphin use different pressures, if I remember correctly even the Atlantis and DOlphin have some minor differences as well..
at 245 psi (its reallt 260psia) its going to exit the sonic range somwhere around 260 fsw, but flow should stil be close enough for the next atmospehere or so..
 
padiscubapro:
Dives like that are planned as a team... We plan enough gas to get 1.5 divers out of trouble..

I usually have the students slinging 2x40's, and for good measure I'll sling 2x80(since I am very confortable with them, and rather make it a bit easier on the students) and have 100% oxygen staged shallow... These are just general guidlines.. each dive is planned based on logistics.. If I'm going down a fixed line its not uncommon to stage bottles at key oints on the line. also I usually pre arrange specific signals to tell the surface support there might be an issue, and we may need gas... Every dive has its own problems and solutions.
I'll be doing some dives in the near future that will require the entire team (3-5 man teams)to carry 80s as bailouts with safety dives also with gas available..

if I am doing with a bunch of experienced divers.. we will truely plan the 1.5x required.


Its been about 2 years (maybe 3) since I played with any of the drager's, so my memeory may be a little clouded, sometime all the specs get blended together... I know the Ray and Dolphin use different pressures, if I remember correctly even the Atlantis and DOlphin have some minor differences as well..
at 245 psi (its reallt 260psia) its going to exit the sonic range somwhere around 260 fsw, but flow should stil be close enough for the next atmospehere or so..

I plan on each dive member having enough bailout to easily complete the dive on OC if things go south at the deepest part of the dive. I am curious about the fraction, i.e. 1.5 - do you mean that you can get yourself an your buddy 3/4 of the way home, or does each dive team member have a 50% cushion in case life really becomes complicated? (I guess you mean the latter).

I think that Batman plans to have all bases covered from a contingency standpoint, and he plans on having plenty of monitoring to make sure that he does not go hyper- /or hypoxic. Modifying the Drager to conserve gas seems like a realistic option, if you begin with the right mix. I personally like as much Helium in my mix as I can afford, however, if I conserve it I can afford more. It is an interesting intellectual exercise as well. Yes I have been trained and I have the manual. I am just hoping to get some knowledge regarding the oportunities available with the Drager.
 
https://www.shearwater.com/products/swift/

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