O2 Sensor Error

[Desert Diver]

Hello all,
So I have a new to me oxygen analyzer with a new MAX-7 sensor. What kind of error should I expect at 100% O2 if I calibrate with air and what error might I expect with air if I calibrate with pure oxygen? If I calibrate with air, oxygen from my welding tank reads about 97%. If I calibrate with the O2 tank air reads about 21.9%. Is this about what would be expected? My interest is for Nitrox use. Thanks for any input.

Brian

[Joshua Smith]

Hello all,
So I have a new to me oxygen analyzer with a new MAX-7 sensor. What kind of error should I expect at 100% O2 if I calibrate with air and what error might I expect with air if I calibrate with pure oxygen? If I calibrate with air, oxygen from my welding tank reads about 97%. If I calibrate with the O2 tank air reads about 21.9%. Is this about what would be expected? My interest is for Nitrox use. Thanks for any input.

Brian

Thats not a bad margin of error. Probably +/- 1%. Keep an eye on it, and just replace the sensor if it stops making sense. And don't push your MODs too hard.

[CaptnJack]

It won't read linear across the entire range.
Calibrate with air for 32-36% nitrox. 50% deco mixes should be plus-minus <1% with an air calibration as well.

Once you get up to 100% the linearity is all off and minus 3% is rather unremarkable. Mine is usually more like minus 98.8% or something like that. But its uses a different brand sensor.

[Desert Diver]

Thanks for the replies. Without any experience I wanted opinions that had experience behind them. Great to be able to get those.

Brian