Explosimeter??
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From: steamer on 8 Dec 2009 13:45 Sjouke Burry <burrynulnulfour(a)ppllaanneett.nnll> wrote: >Measure voltage across a balanced circuit, and voila! you >have a detector. --Not good enough; that's how the current scheme works but it only tells me if there's a non-air mixture, not if it's explosive.. -- "Steamboat Ed" Haas : Currently broke and Hacking the Trailing Edge! : looking for a job... www.nmpproducts.com ---Decks a-wash in a sea of words---
From: steamer on 8 Dec 2009 13:45 --Thanks; will check 'em out. -- "Steamboat Ed" Haas : Currently broke and Hacking the Trailing Edge! : looking for a job... www.nmpproducts.com ---Decks a-wash in a sea of words---
From: Sjouke Burry on 8 Dec 2009 15:24 steamer wrote: > Sjouke Burry <burrynulnulfour(a)ppllaanneett.nnll> wrote: >> Measure voltage across a balanced circuit, and voila! you >> have a detector. > --Not good enough; that's how the current scheme works but it only > tells me if there's a non-air mixture, not if it's explosive.. > Yes it does. The platinum wire catalyses the oxygen/gas mixture, and thereby increase the temperature. The other wire does not, and stays at a lower temp. A temp difference between the two wires signals a combustible mixture, and detects flammable/explosive gas.
From: steamer on 9 Dec 2009 13:43 --Well I still have an issue with false positives, unless there's a linear relationship for output. I guess I could search for a specific temp for a specific mixture then?? -- "Steamboat Ed" Haas : Currently broke and Hacking the Trailing Edge! : looking for a job... www.nmpproducts.com ---Decks a-wash in a sea of words---
From: Sjouke Burry on 9 Dec 2009 19:39
steamer wrote: > --Well I still have an issue with false positives, unless there's a > linear relationship for output. I guess I could search for a specific temp > for a specific mixture then?? > You have to compensate for temperature, and I fear for pressure and humidity as well. I think that thats the reason sensors in this field are so expensive...... Also, the higher the wire temperature, the more sensitivity, but the platinum wires might not like that. Altough it is these kind of things, that make working in research a pleasure. :) |