What Type O2 Analyzer?
- Thread starter Chivas
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
Mark Vlahos
Contributor
Hello,
They pretty much all work the same. I built mine from a kit I got at http://www.oxygenanalyzer.com/YOUDOIT.htm . There are other plans and kits out there if you are so inclined.
As far as purchasing a commercially available unit the features that you should consider are...
user replacable batteries
user replacable oxygen sensor
a flow regulating device (somthing more sophisticated than holding it up to the tank valve)
A kit will cost you less than $100 US and take a couple of hours to put together. A complete unit will cost more but should have a warranty and be ready to go immediately. The choice is yours.
Whatever brand you go with check in to the lifespan of the oxygen sensor and the cost of its replacement, this is the only long term cost worth worrying about. Some sensors last only 1 year while others last up to 5 years, and some sensors cost as little as $60 or so while others can be almost triple that amount.
Mark Vlahos
They pretty much all work the same. I built mine from a kit I got at http://www.oxygenanalyzer.com/YOUDOIT.htm . There are other plans and kits out there if you are so inclined.
As far as purchasing a commercially available unit the features that you should consider are...
user replacable batteries
user replacable oxygen sensor
a flow regulating device (somthing more sophisticated than holding it up to the tank valve)
A kit will cost you less than $100 US and take a couple of hours to put together. A complete unit will cost more but should have a warranty and be ready to go immediately. The choice is yours.
Whatever brand you go with check in to the lifespan of the oxygen sensor and the cost of its replacement, this is the only long term cost worth worrying about. Some sensors last only 1 year while others last up to 5 years, and some sensors cost as little as $60 or so while others can be almost triple that amount.
Mark Vlahos
Chivas:
I got the Oxyspy unit (manual here) because I liked the idea of being able to push a button and just analyze - not having to hook up a reg, etc. On the boats I dive, we take the cylinder over to the station / booster and get blended.
With the other devices I was considering, I'd have to attach something to the cylinder (either a reg, or a cap) so I could send the flow of gas to a tiny tube. This one I sort of pop afainst my DIN valve, crack it open a smidge and it takes a reading.
It calibrates with a touch of a button. The sensor is replaceable, comes with a cool padded case, etc. I got it for about $100 off of eBay a few years ago.
Keep yours in a ZipLock. O2 sensors start burning out the minute you install them. My understanding is they last longer when kept in a bag. Dunno, but mine is still rockin. I checked it against another type of unit on a recent boat trip, and both units were the same reading.
The only thing I can't do is Analyze once the system is together. If you prefer to charge your system then analyze, get one that will fit into your inflator hose. Some people prefer these. I'd rather analyze at the fill station - hence I got the OxySpy.
K
Mo2vation:
Most will do both. My Oxycheq Expedition will read direct from a tank, through the flow restrictor included with the unit, or from a LP line.
The Oxycheq kits will work the same way. I feel using a flow restrictor, line, and LP fitting give the more reliable results.
MD
murphdivers286
Guest
MSP Rescue Diver
Contributor
I bought the Amoxtec O2EII last year at the DEMA show in Miami. Like Moto, I was looking for something rugged and easy to use. The place where I buy gas had one and it seemed to fit the bill. Plus they were only $169 at the show. 
Marc
Marc
I have used the El Cheapo and El Cheapo II that I have built for years. I have compared them to several high priced unit that come aboard and have never seen a 1% +/- difference. I can't be sure it was my unit that was out. It is the best deal in tech equipment I have seen.
I have 2 one is 8 month newer than the other, when I see the one with the older sensor start to go I replace the sensor, then watch the other one.
I have 2 one is 8 month newer than the other, when I see the one with the older sensor start to go I replace the sensor, then watch the other one.
MechDiver:
I was wondering if those units with the little hose had some kind of thing I could screw into my DIN to measure at the blender. Very nice. Plus they're smaller - easier to fit into the drybox. My Oxyspy is just big.
eBay may be calling .... MD you suck.
K
I have a used a couple of different ones. There is the type that you can hold up against a tank valve. These work but I am not a big fan of them for a couple of reasons.
First, their proper use depends on cracking open the tank valve just right to get a proper flow rate moving across the sensor. Too high and you wear out the sensor earlier. With a flow rate that is too low (without some type of gas capturing device), you risk less accuracy in the measurement. Using the types with the flow restrictor makes this easier, consistent and accurate.
I prefer the units that have the oxygen sensor connected at the end of a cable, independent of the main unit, like my Miniox. One reason that I like these is that I can flow my gas through plastic tubing to my Helium analyzer and then take some more tubing, connected to the exiting gas that has just passed over the Helium sensor, flowing the same gas into my O2 sensor at the same time. Maybe you will one day start diving Helium and maybe you won't. This will keep that option open and, in the event you do need to check O2 and He content, you won't have to start pulling out different types of setups for checking each gas; you can just line up your analyzers in series.
If you decide to go with a flow restrictor, consider this: Some people elect to use the type that connects to the low pressure inflator for your BC or dry suit. These are good for checking your mix after your gear is set up. However, other than that case, if you go with the low pressure plug-in flow restrictor, you will have to keep dragging out your regulator when filling and mixing (Make sure it is one of your O2 service regulators for checking high fraction mixes!).
I prefer the flow restrictor that that screws into the DIN connector from the tank valve. It is small and it fits in a small dry box with my O2 and He analyzers. However, I also carry the BC low pressure inflator plug-in type for checking my mix in the field.
First, their proper use depends on cracking open the tank valve just right to get a proper flow rate moving across the sensor. Too high and you wear out the sensor earlier. With a flow rate that is too low (without some type of gas capturing device), you risk less accuracy in the measurement. Using the types with the flow restrictor makes this easier, consistent and accurate.
I prefer the units that have the oxygen sensor connected at the end of a cable, independent of the main unit, like my Miniox. One reason that I like these is that I can flow my gas through plastic tubing to my Helium analyzer and then take some more tubing, connected to the exiting gas that has just passed over the Helium sensor, flowing the same gas into my O2 sensor at the same time. Maybe you will one day start diving Helium and maybe you won't. This will keep that option open and, in the event you do need to check O2 and He content, you won't have to start pulling out different types of setups for checking each gas; you can just line up your analyzers in series.
If you decide to go with a flow restrictor, consider this: Some people elect to use the type that connects to the low pressure inflator for your BC or dry suit. These are good for checking your mix after your gear is set up. However, other than that case, if you go with the low pressure plug-in flow restrictor, you will have to keep dragging out your regulator when filling and mixing (Make sure it is one of your O2 service regulators for checking high fraction mixes!).
I prefer the flow restrictor that that screws into the DIN connector from the tank valve. It is small and it fits in a small dry box with my O2 and He analyzers. However, I also carry the BC low pressure inflator plug-in type for checking my mix in the field.
Similar threads
