O2 + CO analyzer choices.

[WarrenZ]

User option or one decimal.

Would it be possible to get ahold of one before Scubaboard Surge in December?

 

[DeputyTom]

Prefer the accuracy of the decimal

 

[kwinter]

I have to disagree. The decimal place lends a degree of accuracy that just isn't really there. I've complained about the 2 decimal places used by Shearwater in pO2 measurements for years. It makes many people think their cells are off or their electronics are flaky because the last digit dances around. If the analyzer is measuring ppm and a difference of 1 is not huge and deadly, I say remove the distraction of a level of accuracy that is not needed. Whole numbers that are stable are better than decimals that keep changing.


iPhone. iTypo. iApologize.

 

[JohnnyC]

What kwinter said.

I mean really, is a 1 decimal change going to be the deciding factor between diving the tank and calling the dive? If you're going to be that twitchy about a decimal place, I'd hate to see all the other personality traits come out.

CGA Grade E calls for 10ppm or less. Seems a nice round number. Would whether that number was 10.1 or 9.9 on the analyzer be the deciding factor? Personally, I'm not gonna dive it at 9.9, and realistically probably not gonna dive a tank above 5 or 6ppm, so why should I care about a tenth of a part per million? Especially if it delays manufacture.

 

[seaseadee]

I use the O2 analyzer at our LDS and it does go to 1/10th of one percent but doesn't jump around like you describe. What would cause the difference in behaviors?

Edit: if this question is only for CO measurements then I agree with what kwinter said.

 

[kwinter]

I use the O2 analyzer at our LDS and it does go to 1/10th of one percent but doesn't jump around like you describe. What would cause the difference in behaviors?

Edit: if this question is only for CO measurements then I agree with what kwinter said.

Because 1/10th of one percent is one part per thousand. The decimal place he is talking about would measure to one part per 10 million.

 

[JohnN]

Prefer the accuracy of the decimal

Don't confuse resolution with accuracy.

 

[rhwestfall]

my bad.... I really didn't read the question well enough, thinking we were discussing the output display of both. As to just the CO, there is no need for the decimal. EAN, I'd still like to see it.

 

[DiveNav]

Does the underlying accuracy of the CO sensor support 10^-7 resolution?.....

Yes.
The sensor we use is an high resolution sensor optimized to operate in the 0 to 200ppm range.
Furthermore, our system is specifically designed for scuba diving and it is optimized to operate in the 0 to 20 ppm range (we calibrate it with 0 ppm and 20 ppm gasses). In this range, every ppm has several bits of resolution.

---------- Post added October 30th, 2015 at 09:54 AM ----------

Would it be possible to get ahold of one before Scubaboard Surge in December?

When and where is that?

 

[seaseadee]

Is the error factor for the sensor less than +/- 10^-7?