Need replacement oxygen analyzer for intermittent use. Long lasting sensors?

[walkonmars]

Hi Folks,

The oxygen sensor for my analyzer failed on me again. (After around 18 months.)
I only use it intermittently every several months or so and some would argue 18 month life from a sensor is pretty good. I was using an Oxycheq home built version with the panel meter and R-17S sensor.

I could replace the sensor and be on the road again or simply buy a new dedicated factory unit.
One of the dive boats I charter on a lot uses the Nuvair cylinder/stick shaped version and the thing is used all week long, sits in the sun, gets moisture on it and gets banged around but always seems to work fine.
Any suggestions for models that have sensors that last longer than 1 year with intermittent use?

Thanks,
Tom

 

[Astran]

Why can't you just analyze the tanks when you pick them up from whomever filled them?

 

[walkonmars]

I partial pressure blend my own gas. I have a preference for EAN36 and mix pony bottles with 50% and greater oxygen.

 

[Pao]

I made my own Arduino based analyzer which is sensor brand neutral/agnostic and just buy any "reasonably priced" sensor such as the ones offered by Dive Gear Express. DGX also has a sensor for the palm D that claims to have a 36 month life. I might try that once my current one is consumed.

 

[Johnoly]

... suggestions for models that have sensors that last longer than 1 year with intermittent use?...

I have the Analox O2EII and use the manufacture's sensors. I magic marker the date on it and get 3-4 years from them. I've tried aftermarket ones and only got 18 months like you said. Several years ago at the DEMA show, the Analox tech showed me how & why their sensors last longer. There is a 'stretch-able' membrane cover over the top of the sensor. As air pressure is applied from a tank sniff, the membrane weave stretches and opens to allow the sample thru it so the metal sensor can react to it and gives off a voltage that's read. That stretchable membrane is what keeps the metal sensor from degrading with exposure to air. The key to longer O2 sensor life is to limit the sensor to air movement (and the quality of the metal reaction inside). The manufacture's sensor costs me about 30% more than the aftermarket types. I dive almost every week with 3 tanks that I check and all I know is that they last much longer. P.S. Get a CO sensor also like @DandyDon has many writeups on different types..

 

[Jeremy Williams]

The sensor is a galvanic fuel cell. To make it last 5x as long as it would you just have to block access to the fuel.

https://www.oxycheq.com/sensor-saver.html

 

[walkonmars]

Thanks,

Over the long run it does make sense. Get a unit that lasts 2 or 3 times longer for a little higher price is better.
It seems better not to worry about the "petty" problems with sensor failures and focus more on the task of diving. I'm likely sold on it unless others have additional suggestions for long lasting sensors.

 

[runsongas]

if you have an argon bottle for suit inflation, you can flush the cell with that and then cap it. kinda the one good use for that.

 

[NAM001]

cap it and it shoudl burn up the O2 and seal it in a zip lock bag when not in use. It will take a while for it to work again after re-exposed to O2 atmosphere. Mine lasted 5 years.

 

[happy-diver]

Over here on my speck of the English speaking world
I manufacture my own stretch-able membrane from
a sheet of rubber, with a punch, to fit inside the cap

for threaded caps seals
Pure Pulitzer Prize gold