Helium Gas Analyzer

[AquaTec]

I use the Dive Rite He analyzer

I love the simplicity of it, I can either plug it in or use batteries

It is great for top ups. and confirming exact gas mixes.

i want to be acurate with the amount of He and O2 i have
i don't like to guess or use some type of voice test.

 

[Fort Collins Bob]

omar once bubbled...
This is a little more advanced than an oxyhacker oxygen analyzer using a panel meter. You will need to put the TCC's into an appropriate circuit.

Hello all,

I was planning on using a single chip microproccessor ( PIC CHip)
to do all the magic with... and I have the programmer to do it with.

A little a/d conversion and I should be in the market.

I was hoping on finding some information about the cells ( TC's )
themselves. Manufacturer, spec's ...

Thx all ;-]

bob

 

[Uncle Pug]

ftcbob once bubbled...
Thx all ;-] bob

Bob.... forgot all about you Bob.... let us know how it works once you get it all figured out... ;-]

 

[Braunbehrens]

AquaTec once bubbled...
I want to be acurate with the amount of He

Not that there is anythign wrong with using a He analyzer or being accurate, but I'm just curious, why do you feel it's so important to be accurate with the amount of He?

 

[sheck33]

ftcbob once bubbled...

omar once bubbled...
This is a little more advanced than an oxyhacker oxygen analyzer using a panel meter. You will need to put the TCC's into an appropriate circuit.

Hello all,

I was planning on using a single chip microproccessor ( PIC CHip)
to do all the magic with... and I have the programmer to do it with.

A little a/d conversion and I should be in the market.

I was hoping on finding some information about the cells ( TC's )
themselves. Manufacturer, spec's ...

Thx all ;-]

bob

I am by no means an expert on this but i think the actual cell can really have a variety of shapes and sizes. However a small size is better. What could be done is put a thin filament, identical to the ones used in gas chromatographs, in the cell and flow the gas through the cell, the filament would be used in a Wheatstone Bridge configuration. How linear the resistance change would be with He content i dont know, but it can be calibrated.
Filaments are usually in the 30- 50 Ohm range with a maximum current of about 100 mA. The max current however very much depends on the rate of gasflow.

anyway, is this somewhere along the lines of what you were thinking about

 

[Charlie99]

Uncle Pug once bubbled...

I dunno Charlie... since I already have my flow gauges marked for various mixes I could probably get by if the helium analyzer went down but I don't know how easy it would be to get started without one.

What works in theory might not be so easy IRL.

I guess you haven't heard that Helium Analyzers Rot Yer Brain.

If you try running the He/air mixer output at 9%,and the final mix at 18%, you just might find yourself with 18/50.

You do need to fully mix the gases twice, but I hear Scott Koplin up in your area makes some pretty nice vortex mixing tubes.

Since all the gases are being blended at 1ATA, the nonlinearities of the pp mix methods are avoided. The only real downside is that a percent or two error in O2 in the first mix (air/He) turns into several percent error in He. In other words, if your first mix is 10% O2 rather than 9%, then you end up with 18/46 trimix, rather than 18/51.

Charlie

 

[Uncle Pug]

Charlie99 once bubbled...
I guess you haven't heard that Helium Analyzers Rot Yer Brain.

That must what happened alright Charlie. I don't figure in my poor state of mentation I could balance a stack of blenders.

Have you ever tried it IRL?

 

[Charlie99]

Nope, I never touch the devil's gas :mean:

Just hearsay.

 

[BigJetDriver]

Just as a note, I have an Atomox and the Qxycheq Expedition. Sure does make the job a lot easier!