O2 sensors.

[Finless]

I never noticed [EDIT] I DON'T REMEMBER IF (when I bought my O2 cell) there was any information on the best way to use the cell?

All the commercial O2 analysers seem to rely on a constant flow of gas over the sensor surface?

I currently use the 'squeeze a bag with the wired up sensor in it over the reg mouth piece, purge the reg and fill the bag with gas to be analysed and keep adding gas IF the bag goes floppy.

The sensor just fits nicely into the cylinder valve (where the din bit screws in) and if I can get a slow enough gas supply I can get a constant reading?

I have seen advertised an off the shelf item that looks like a plumbing T piece and that worked on the idea that the gas was kept going until you were sure all the original air in the T piece was purged and then turn off the cylinder and the one way valves in the T piece kept the gas to be analysed trapped in the T piece.

So ........ any ideas as to which gives the most accurate reading? I've stuck with my bag method because it's cheap, doesn't waste gas and I've not suffered any ill efects from my O2 measurements.

[Woz]

I use the T piece thingy from Vandagraph that the o2 sensor screws into. It's idiot proof. Plug in- switch on, calibrate, fire in O2, see what it is, walk off. Takes about 30 secs.

vandagraph.co.uk

[Finless]

Originally Posted by Woz

I use the T piece thingy from Vandagraph that the o2 sensor screws into. It's idiot proof.

That works on measuring a static volume of gas ....... as in there is no flow of gas through the T piece?

Aren't they about £20?

[Woz]

Originally Posted by Finless

That works on measuring a static volume of gas ....... as in there is no flow of gas through the T piece?

Aren't they about £20?

Yes. And yes. You switch on the gas and it traps a volume in the T piece- it's got a fancy 1-way valve in there. I use mine with my Oxyguess and it works very well, something I cannot say for the array of 2nd hand dodgy cells I appear to be accumulating at a rapid rate. The current one is very accurate al the way to 100% (to within a nothingth) but does require a clout every now and then to get going. I don't see it lasting long and I'll be on the scrounge again soon.

[Finless]

Originally Posted by Woz

Yes. And yes. You switch on the gas and it traps a volume in the T piece- it's got a fancy 1-way valve in there. I use mine with my Oxyguess and it works very well, something I cannot say for the array of 2nd hand dodgy cells I appear to be accumulating at a rapid rate. The current one is very accurate al the way to 100% (to within a nothingth) but does require a clout every now and then to get going. I don't see it lasting long and I'll be on the scrounge again soon.

I don't remember where I bought my sensor but I'm sure it was under £20 new? The relevant info may still be available in the YD archives ........................

Thanks for the info.

[Woz]

Originally Posted by Finless

I don't remember where I bought my sensor but I'm sure it was under £20 new? The relevant info may still be available in the YD archives ........................

Thanks for the info.

If the sensor is under £20 then I'll 1. take your arm off and 2. give you a big kiss when we meet and 3. might even lick your face too if you are lucky or 4. buy you a pint of warm cloudy southern beer

[Finless]

Originally Posted by Woz

If the sensor is under £20 then I'll 1. take your arm off and 2. give you a big kiss when we meet and 3. might even lick your face too if you are lucky or 4. buy you a pint of warm cloudy southern beer

Oh well ............. maybe it's my poxy memory playing tricks though .......... I'm off to search the archives ..............a big kiss you say ?

[Finless]

Woz, although unitentionally and due to a bad memory I have to admit I lied! Sorry!

Omni Components Ltd

Woz - is this somewhere you tried?

[Woz]

Originally Posted by Finless

Woz, although unitentionally and due to a bad memory I have to admit I lied! Sorry!

Omni Components Ltd

Woz - is this somewhere you tried?

Nope. Any idea on the £££?

[Finless]

Originally Posted by Woz

Nope. Any idea on the £££?

No - apparently not!

I do know they were the cheapest I could find at the time. Payment had to be by cheque as the margins were so tight that credit card charges were not acceptable.