Sensor checking

[Ahmed Adly]

I was watching Richard Pyle's interview about the MARKVI rebreather and I found the unit to be pretty interesting. The main point I liked was the new oxygen sensor thingy that samples your bottom mix at your request, therefore allowing you to make your own calculation as to weather your sensor is operatin properly.

The reason I liked it mainly is becasue you only then really need your main one and a backup in case one fails.

My question is how can this be done on the KISS?

[deepbull]

Originally Posted by Ahmed Adly

I was watching Richard Pyle's interview about the MARKVI rebreather and I found the unit to be pretty interesting. The main point I liked was the new oxygen sensor thingy that samples your bottom mix at your request, therefore allowing you to make your own calculation as to weather your sensor is operatin properly.

The reason I liked it mainly is becasue you only then really need your main one and a backup in case one fails.

My question is how can this be done on the KISS?

try a dill flush ????

[Ahmed Adly]

Originally Posted by deepbull

try a dill flush ????

How many Dil flushes can you perform with a KISS during on a 3 hour dive?

[nigelH]

I'm not a Kiss diver but knowing the way that galvanic sensors work and reading about how they fail my preference is to boost the oxygen not depress it. I want to see the cell read a value that is higher than my control points so I can have confidence in the readings that are lower than that.

Once I have seen that I am confident that the next few hours of operation should be reasonably angst free so it tends to be an oxygen flush on the 6 meter stop near the end of a dive and I want to see 1.5 something.

I've had a Classic Inspo throw me a 'Cell Error' at 60m and I really don't need that too often in my life.

[deepbull]

Originally Posted by Ahmed Adly

How many Dil flushes can you perform with a KISS during on a 3 hour dive?

if the MK IV is continuous calibrating how can it work?
putting your life in the hands of just 1 cell well time will tell and then they say this
''AND YOU CAN FORGET ABOUT EVERYTHING YOU HEARD ABOUT PO2''

{a nice size o2 cylinder 3ltr 100bar ? } why?


if you have a kiss do a dill flush then if the cells are ok whats the problem?
if you don't trust the cells don't dive!

what do you think about this tho?
no need for OC now you only need to be able to swim

LEVEL 1 CCR COURSE CONTENT

“Your Entry into the Marine World - Enjoy a Bubble Free Environment”

As a RAID Diver you will savour every moment of weightless exhilaration, where you will meet other adventurers who share your quest for unending excitement, meet new people and have a great time.
<h3>PURPOSE OF THE COURSE

This course is designed to train you in the safe use and technology of basic Closed Circuit Rebreather diving with no decompression, up to 1.2 PpO2 and to a maximum depth of 20 metres/66 feet.
PREREQUISITES, in addition to the General Course Content for All Levels:

• Be able to swim comfortably.
• Be a minimum of 15 years old.

</h3>COURSE CONTENT

• On-line e-learning academic presentations, quizzes and exam.
• Confined water (pool) and open water (sea/lake) sessions, totalling a minimum of 6 hours underwater on a RAID registered rebreather.
• On-line certification.

IN WATER TRAINING

Your initial training will be in a low-stress environment (pool) for the basic skills. Your instructor will demonstrate each skill for you to practice and master. Your instructor will also ask you to perform a 10 minute float without any equipment and a 200 metre/660 feet swim, with no time limit - just to determine you have basic swimming skills.
You will then move into the open water for your four qualifying dives. Here you will learn new abilities and explore the underwater world, with your instructor guiding you. Just remember, all skills are under your instructor's guidance and supervision.
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Remember: you can register for more than one academic course at a time. During in water training, you may wish to directly follow onto the next course. Certification by a RAID instructor will be on completion of all the in water training.

[Mark Chase]

Originally Posted by Ahmed Adly

I was watching Richard Pyle's interview about the MARKVI rebreather and I found the unit to be pretty interesting. The main point I liked was the new oxygen sensor thingy that samples your bottom mix at your request, therefore allowing you to make your own calculation as to weather your sensor is operatin properly.

The reason I liked it mainly is becasue you only then really need your main one and a backup in case one fails.

My question is how can this be done on the KISS?

With a great deal of dificulty.


Turn off 02, inject 02 into loop and dill flush it out of the lungs via your personal internl lungs . I dont fancy this at great depth. Monster 02 spikes will occure. Fill lungs and empty them three times. Read sensors.


OR

Leave 02 on, quickly empty counter lungs and flush with dill three times and quickly see the pp02 reading bounce to a low point as you watch the hand set. This is what i do and its close enough for jaz.


On inspo or simila:

Switch to low set point and flush lungs three times with diluient.

ATB

Mark

[Mark Chase]

Originally Posted by Ahmed Adly

How many Dil flushes can you perform with a KISS during on a 3 hour dive?

How deep are you and what size dill tanks are you using? Gas laws apply even to CCR.

ATB

Mark

[NotDeadYet]

I'm not entirely convinced about it. Great idea but you've introduced many levels of complexity to do away with one cell. Big deal. And if one of your two cells has failed then you are now down to one cell. Are you going to trust that to run your RB? I'm afraid I'd be either on SCR or bailout at that point.

I find the KISS when the cells are happy will react quite fast to a little bit of dil. If it doesn't react then worry. Sometimes seeing Gordon's "dancing digits" is as important as a dil flush -- it's telling you the cells are doing something.

Running a KISS is a holistic approach, you need to be aware of hearing the O2 hiss, manual O2 addition, the ADV, the OPV, depth changes and the displays. If you concentrate on JUST the displays then you substantially reduce your chances. I'm sure that applies to all rebreathers but on mCCR when you stop thinking then you stop breathing. It is absolutely not a passive rebreather, you need to be on top of it rather than just watching a display.

I hook my BOV into my offboard bailout. If I can't afford a couple of breaths off my bailout for flushes then I've undersized it. You need however much gas makes you happy and if a lot of flushing makes you happy then carry the gas.

Cheers,

Stuart

[Ahmed Adly]

Hi,
I am not really trying to do away with a cell. I am trying to achieve a more self (brain) sufficient way of verifying the sensors validity.

I now understand that a full flush would not be best, seeing that you cannot do it all the time.

I suppose it is good enough as it is. Thanks for your answers

[Janos]

I spike my O2 cells regularly to check they are not current limited, and I know they are calibrated at the start of the dive. If one is dodgy mid-way through the dive, then I still have two working cells to use.

You get a 'feel' for how your cells behave, and you do know your ppO2.

Janos