Jan Bruggeman
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Jan Bruggeman from Gent Belgium build his own MCCR. Check this out. Jan thanks for your contribution!

1) The basics:

A case with 2 bottles attached: 5l diluent (gives me some on-board bailout) and 3l Oxygen.  

2) The important thing:

The breathing loop consists of an original Dräger Dolphin loop. 2 changes have been made:
  • overpressure relieve valve and p-port for injector piece have been switched: relieve is now on inhale lung and p-port on exhale lung.
  • A T-piece has been added to accommodate the 3 O2 cells.

3) The technics:

Consists of 2 parts: diluent and oxygen.
  • Diluent is added thru a regular first stage (picture: extreme right), connected with the old ADV of the Dräger (picture: second from right), which works just like any other seconds stage. As the original Dräger first stage operates on a higher intermediate pressure as a regular first stage, I had to change the ADV spring for a lighter one. The other 2 hoses on the first stage are for pressure gauge and for wing inflator/bailout regulator.
  • Oxygen is added thru a regulator (picture: extreme left) which has been adapted to give a fixed intermediate pressure. From there it goes to the kiss valve (picture: second from left) which provides the loop with a constant flow of oxygen. The valve also contains a shut off and a bypass button. The other 2 hoses on the oxygen first stage are for pressure gauge and oxygen bailout regulator.

4) The electronics:

Nothing special, just a triple 02 meter. No logic inside. And not really fully triple redundant: only one battery, one casing, one cable. All single point of failure's.  

5) And the regular stuff:

I use my "old" back plate and wing. The wing has an Air2 as inflator piece, which will also be usable for my on-board diluent bailout.  

How to fit all this toghether:

First put the breathing loop inside the box.

Attach the mechanics to it. Here you see one reason why P-port has been shifted to exhale bag: so the connections to the loop are made at the exterior. Another reason is that this way your gasses which are injected here, first have to pass thru scrubber and inhale lung, before they are measured. This gives the mixture more time to "mix".
add the basic stuff (back plate and wing) on top, and finish connections.
Don't forget the electronics, they just plug into the T-piece.

Here's how it looks underwater:

You can see I wear separate bail-out at all times ! Dry-suit inflation is also attached to this
Here you see that the Alu 5 l is positive, the steel 3 l is negative. I've put 1kg of lead inside the box at diluent side to compensate.

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