Quote:
| Originally Posted by frogman-JCA Hi there,
As a recently converted rebreather diver who has completed the Drager rebreather course and purchased his new toy, I and thinking to extending my dive times and reducing my deco times by introducing a high O2 content mix into the loop. I understand the is a manufacturer who makes a adaptor which will allow a additional first stage to be connected to the dosage unit allowing the deco mix to be turned on for the stops and the bottom mix to be shut down, thus allowing a richer mix to flow into the loop. Does anyone know who can supply these fittings and do they have any contact details? Has anyone used one of these fitting and experienced any problems? I’ll welcome any advice from anyone who dives a rebreather
Regards
John |
Tries to remember SCR.......
firstly the fitting, look here ->
http://www.inspirationtraining.com/d...r_trainer.html
or here
http://www.tecme.de/frame_eq1.htm
Highly reccomend the second link, nice guy called Martin.
The deco fitting plugs into the 60% or similar fitting which raises the FO2 in the loop, but too slowly (5.5ltr/min) to boost the loop FO2 nicely.
You need to tee it into the ADV aswell or have a manual add valve so you can flush the loop and raise that PPO2 quickly to make it worthwhile.
If you dont, you wont get past 60% FO2 before your deco is over and then what was the point of filling another cylinder with pure?
One of the problems with this is the pipe salad you will have if you dont do it properly, and the potential for feeding the wrong gas at depth by accident or by knocking the valve. Monumental screw up potential.
Having said this, my swagelok valve was removed this weekend for one reason or another and I flew my RB manually using a similar system directly off the knob. So it is possible.
I would suggest a 'Bob's bits' manifold or a Ray manifold connected through the supply gas. If you cant get one then go to
http://www.tecme.de/frame_eq1.htm and get some 'tee' peices.
One last thing, very important.
If you shut down your bottom mix, and open your pure O2 without connecting to an ADV the loop will not replenish gas you blow off. So if you descend(not below the MOD of course!!) or clear your mask, your loop will not have sufficient gas for a lung cycle.
ADV is a must, bouyancy is a must, gas switching discipline is a must. If you plumb it right, its a peice of piss.
Other than that, its a cool way to learn your way to bridging the gap to CCR.
Hope that helps. Green button at the top right please!!!