Sensors: which gas shall I have in the loop when not in use?

[tbone1004]

OK, OK, I got it. In future I will break down the unit right after dive and store the cells in air.

The question if cells shall be changed at a different time or all together is an old one. If we want to discuss this interessting point we probably should open a new thread.

The rest is clear anyway: know pO2, maintance, assembly, testing. My definition of rebreather: gas prolongation apparatus, sitting in your neck, trying to kill you.

they should be changed as they fail. Having all of them from the same lot increases probability of a group failure. It is less severe on a Liberty because you can manually disable cells, but on everything else it can cause problems with voting logic

 

[Wibble]

For building the unit? No, not for building, that's what you learn on the course by hart. Liberty's checklist tells you what to do after building.

Does it include analysing the gas & pressure? Yes, of course.

Checking your bailout gas and regulators? Yes, of course.

Checking and greasing O-rings? That's part of the building. If an O-ring is leaking, you find out during under- and overpressure test, part of checklist.

Over pressure valves on wing and lungs? Yes, of course.

Checking weights? Yes of course.

lights? Yes of course.

suit inflate? Yes of course.

My point is that a written checklist forces you to properly build the unit and helps prevent you missing a step.

I’ve kept all of my build sheets so I know when cells are change and I can compare how cells change. Even note down when batteries are changed (SAFT in the Shearwater Petrel, PP3 controller)

 

[broncobowsher]

I have had enough mass produced stuff that came in batches that are built the same. Perform the same. And fail the same. By mixing batches, you mix the failures. Even if built the same way, the time shift will move the failures. Slightly different mix of electrolyte between batches, you are adding variables to the failure points. This is good, it makes the failure stand out.

I have been out of diving for several months (due to knee injury) and am getting ready to dive again. I started getting fresh cells. I ordered one. Month later, out of stock, back in stock, ordered another cell. They are different batches. If there is an early failure, it is much less likely that both cells, built at different times, in different batches, will fail at a matched rate.

 

[Jimchris]

Oops! We ran into some problems.​

The requested page could not be found.

Understanding oxygen sensors

http://www.revo-rebreathers.com/wp-content/uploads/2016/02/Understanding_oxygen_sensors.pdf

Understanding oxygen sensors part II

http://www.revo-rebreathers.com/wp-content/uploads/2017/01/Understanding-Oxygen-Sensors-part-II_the-complete-picture.pdf

 

[evandroairton]

I've just made some vynil adhesive COMPLETE checklists and put them on the canister of both my inspirations, and also ALWAYS take a written check list with me when using the Sidewinder.
Checklists are not just for use during the course, but even more important AFTER, when you don't have an instructor behind you.
I know that i can build both units by memory, but after a while we can get overconfident and skip crucial points.
Losing some very litle time looking and following checklists Will not hurt, and, apart from electronics checklist and reminders (inspo vision also have) loop integrity (pos and neg), mushroom valve checks, connection checks, and so are Paramount for safe ccr diving.
A loose o'ring maybe a cause for a flood, or a CO2 breakthrough, so, in a pinch, why not check It?

 

[Agro]

they should be changed as they fail. Having all of them from the same lot increases probability of a group failure. It is less severe on a Liberty because you can manually disable cells, but on everything else it can cause problems with voting logic

I do not agree, we had this discussion befor. I prefere changing them all together but let's discuss this in an other thread.

 

[Agro]

My point is that a written checklist forces you to properly build the unit and helps prevent you missing a step.

I’ve kept all of my build sheets so I know when cells are change and I can compare how cells change. Even note down when batteries are changed (SAFT in the Shearwater Petrel, PP3 controller)

Nothing wrong with that. Liberty alread has a very good checklist onboard. If written or not does not matter.

 

[tbone1004]

I do not agree, we had this discussion befor. I prefere changing them all together but let's discuss this in an other thread.

I do not believe you will get any experienced CCR divers on this board to agree with you, many of whom are CCR instructors and instructor trainers, but if you want to start a new thread on that go right ahead.

 

[Agro]

I do not believe you will get any experienced CCR divers on this board to agree with you, many of whom are CCR instructors and instructor trainers, but if you want to start a new thread on that go right ahead.

Liberty, change O2 sensors all together or not? This thread already exists.

 

[happy-diver]

Oops! We ran into some problems.​

The requested page could not be found.

Understanding_oxygen_sensors.pdf

Mate google the sentence and see what you can see

https://www.google.com/search?q=Understanding_oxygen_sensors.pdf&rlz=1C1ONGR_en-GBAU943AU943&sourceid=chrome&ie=UTF-8

What do you do underwater, write a letter