Gas Analyser U/S

[Martin King 2Participant @martinking2]

Hi All,

Bought a bunch of instruments at auction last week and have started going through the items.

One is this O2 analyser for welding use.

It is supposed to have a 4 digit readout between 0 and about 25% (O2)

so should read approx 20.84 when fired up. With a new battery it shows this readout;

and nothing happens when the pump is used.

The main agent wants a whopping £150 for a new sensor which sound like a lot.

Would anyone know if these parts are available for other uses etc?

Any thought swould be much appeciated.

Regards, Martin

[Martin King 2Participant @martinking2]

O2 analyser with problem

[Ian Johnson 1Participant @ianjohnson1]

It looks very similar to the sensors fitted in confined space entry multi gas detectors.

Try contacting hire shops who sell or hire Crowcon gas detectors or similar devices. I recommend you speak to the service dept guys not the sales office.

Edit: similar to those fitted to the Crowcon Triple plus+

IanJ

Edited By Ian Johnson 1 on 10/08/2020 17:11:26

[David JuppParticipant @davidjupp51506]

Almost certainly the cell is exhausted. Typically an electrochemical cell, that is used up in presence of oxygen regardless of whether the device is turned on.

To extend life – some users cap the cell to keep air out, others nitrogen purge it after use.

Hardly mass market stuff, so won't be cheap. Is it an 'Analox' brand?

[Ian Johnson 1Participant @ianjohnson1]

Posted by David Jupp on 10/08/2020 17:08:26:

To extend life – some users cap the cell to keep air out

These are the same sort of people who put the detectors in plastic bags to keep them dry, and these are the same sort of people who die in confined spaces!

[Martin King 2Participant @martinking2]

Brand is MasterPurge 100

[not done it yetParticipant @notdoneityet]

Back a long time ago, we used an Orsat gas analysers. Electronic gas analysers were available (1970s), but the sensor cells were short-lived and very expensive. Electronics have got cheaper but the cells, while cheaper in real terms, still seem to be an expensive service item.🙂

Question might be: Will it work, even if you buy a new cell?🙂

[David JuppParticipant @davidjupp51506]

Ian, capping or purging the cell not only extends life, it gives much faster response time if measuring low oxygen levels (for example ppm of oxygen in hydrocarbon gases).

These sensors are used for a very wide rage of analysis – there's nothing wrong with capping or purging the sensor when it isn't being used. Obviously NOT if it is being used to continuously monitor breathing air.

[Ian Johnson 1Participant @ianjohnson1]

That makes sense If it's not being used in confined spaces

IanJ

[Martin King 2Participant @martinking2]

MMmmmmmm! Going in the bin I think! Thanks for the info.

Martin

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