Nitrox/Oxygen Analyzers

[BiancaC]

I use those since several years on our boats, work very well.
You can calibrate on ambient air. Pull the green plug and wave it a bit around.
It comes with an offset chart, that tells you how to correct depending on temperature and humidity. You will see when the sensor starts to go bad, you can't get a stable reading.
It usually helps to open the unit and dry it out, but that is only a temporary fix.
Time to get a new sensor.

 

[mts0628]

Worthwhile investment?

I was looking at this one...
AmoxTec Analox O2EII Nitrox Analyzer

What are some other ways to calibrate? The only one I know of is analyzing regular air at 21%. What if it's just you and a buddy only diving Nitrox and there is no regular air available to calibrate using that method?

$130 to replace the sensor after 4 years... That's nearly half the price of the entire device =-O What are some signs of the sensor going bad, just cross-checking with other devices?

Hey Sonic04GT:

This is an analyzer perfect for recreational diving. As with most instruments, this one is calibrated with ambient air and provisions are made for the temperature and humidity (using a supplied chart).

I own the Portable O2 instrument from Analox and have owned it for about 9 years. I have changed the sensor twice and the unit is bulletproof. I mention this as an example that replacement sensors are reliable and can be gotten. I got mine from OxyCheq, and depending on your model, you can get a replacement for less than 100 USD. Give them a call if you have any questions as they can help you out.

I hope this helps.

With kind regards,
Thomas

 

[Don Wray]

I have the one you reference. It does calibrate on ambient air as mentioned. The sensor is prorated, I don't have a prorate chart in front of me but it's less than the $130.

 

[tedj101]

The only thing that I would add is that as the sensor wears out, you can't calibrate it very high. By the time it won't calibrate above say 21.8, you are close to the end and should buy a new sensor.

OK one more thought. I bought an analyzer after I found that some analyzers that were offered for my use were in pretty awful shape and I didn't trust them. Perhaps I am paranoid, but I like to feel sure that I am taking adequate precautions. Of course most analyzers I see at operators are just fine. But any exception is too much for my taste. FWIW, I find a lot of people asking to borrow my analyzer...

Regards,
<TED>

Hey Sonic04GT:

This is an analyzer perfect for recreational diving. As with most instruments, this one is calibrated with ambient air and provisions are made for the temperature and humidity (using a supplied chart).

I own the Portable O2 instrument from Analox and have owned it for about 9 years. I have changed the sensor twice and the unit is bulletproof. I mention this as an example that replacement sensors are reliable and can be gotten. I got mine from OxyCheq, and depending on your model, you can get a replacement for less than 100 USD. Give them a call if you have any questions as they can help you out.

I hope this helps.

With kind regards,
Thomas

 

[Web Monkey]

While this statement is true, most of these units do not have a pump on them and can not draw the outside air in and therefore the outside air we breathe is useless when calbrating these units.

According to the docs, the analox can be calibrated using room air.

I calibrate my OMS the same way if I don't have a tank available.

It can be off by a few 1/10's of a percent doing it this way, but it's close enough for my needs. I generally don't care if I have 31.7 or 32.

Terry

 

[Web Monkey]

every dive shop I use for fills has an analyzer.
just haven't found an excuse to buy one yet

My excuse was when I was in Tobermory and watched the girl at the dive shop "calibrate" their analyzer by putting it on my tank, cranking the knob until it said "32"

Then she turned to me and said it's "32%".

Terry

 

[LiteHedded]

My excuse was when I was in Tobermory and watched the girl at the dive shop "calibrate" their analyzer by putting it on my tank, cranking the knob until it said "32"

Then she turned to me and said it's "32%".

Terry

lol nice
well I always calibrate and analyze it myself

 

[charlesml3]

I found that some analyzers that were offered for my use were in pretty awful shape and I didn't trust them.

I hear this argument for buying your own analyzer quite often. It still doesn't make sense to me.

So you're saying you DON'T trust their analyzer, but yet you DO trust them to fill your tank with something other than carbon monoxide, carbon dioxide or farts?

If you don't trust their analyzer the you really shouldn't trust their fills.

-Charles

 

[charlesml3]

My excuse was when I was in Tobermory and watched the girl at the dive shop "calibrate" their analyzer by putting it on my tank, cranking the knob until it said "32"

That's really pointing out why it's a good idea to calibrate the tester yourself. It's still not a very compelling reason to buy an analyzer.

-Charles

 

[ivobj]

They seem to be good for about 18 months (I guess longer if you take them out of the device and put them in the refrigerator when not in use).

That's new for me, thanks for the tip, I'll put mine in the fridge!!