Rebreather World - View Single Post - Would an integrated O2 tank pressure monitor be safer?

***jradomski*** · 19th March 2008, 05:44

Quote: (Originally Posted by Drmike)

Hmm, are you sure about this?

Plenty of helium gas pressure sensors around, so far mine on Boris has been perfect (Ive used up to 90% He)

yup... how screwed up it gets depends on the type of sensor and where the reference chamber is... if its a sealed absolute pressure sensors it will become inaccurate pretty quickly as there is only a ver small reference chamber.. if ts a differential sensor in a larger (or open) chamber, it will take longer to get screwed up (or not)... under stress the he molecule can diffuse across the stressed membrane (typical strain type sensor).. More expensive capacitive sensors can be used..

Pressure sensors like those used in mixing panels generally have an open side of the sensor so they would not see a problem, its primarily devices that need to be sealed..

also teh price people pay for the boris, its a possibility that a capacitive sensor is used... WHen I researched this a while back, the cheapest usable solution I found was in the $700 price each in large quantity..

19th March 2008, 05:44	#6 (permalink)
*jradomski* Moderator Current Rebreather/s: Inspiration Classic Sport Kiss Optima rEvo Other CCR Home Build Other Rebreather/s: Inspiration Vision Evolution Megalodon Classic Kiss rEvo Other CCR Home Build Join Date: Mar 2005 Location: "Da" Bronx Posts: 3,004	Re: Would an integrated O2 tank pressure monitor be safer? Quote: (Originally Posted by Drmike) Hmm, are you sure about this? Plenty of helium gas pressure sensors around, so far mine on Boris has been perfect (Ive used up to 90% He) yup... how screwed up it gets depends on the type of sensor and where the reference chamber is... if its a sealed absolute pressure sensors it will become inaccurate pretty quickly as there is only a ver small reference chamber.. if ts a differential sensor in a larger (or open) chamber, it will take longer to get screwed up (or not)... under stress the he molecule can diffuse across the stressed membrane (typical strain type sensor).. More expensive capacitive sensors can be used.. Pressure sensors like those used in mixing panels generally have an open side of the sensor so they would not see a problem, its primarily devices that need to be sealed.. also teh price people pay for the boris, its a possibility that a capacitive sensor is used... WHen I researched this a while back, the cheapest usable solution I found was in the $700 price each in large quantity.. __________________ Joe Radomski CCR Trimix Instructor Trainer ANDI Instructor Trainer Director #10 All posts are personal opinions and DO NOT reflect any affiliated agency unless specifically stated. Last edited by jradomski : 19th March 2008 at 05:51.
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