A protection against explosive gases doesn´t have to be expensive. With the sensor Figaro TGS6812 with a linear output, you can design a quality and price-affordable device, detecting a wide variety of explosive gases.
Destructing effects of gas explosion are very frequent. In many cases, already a simple detector would be sufficient to warn in time about a possible danger. For this purpose, but also for more demanding applications, it is very suitable the Figaro TGS6812 detector of explosive (combustible) gases, with a high sensitivity to methane, propane, iso-butane and hydrogen.
It is the catalythic type detector, reacting on many explosive (combustible) gases, including natural gas, hydrogen and LPG, with the detection range of 0-100% LEL. Thanks to the fact, that the sensor contains an adsorbent in the sensor cover, it is much less sensitive to alcohol vapours, than traditional catalytic sensors. Moreover TGS6812 is more durable against silicone compounds than usual sensors. A big advantage of the sensor is, that it comprises of two elements: one element is sensitive to combustible gases, second one – reference, is not sensitive to gases. These elements are connected into a „Wheaston Bridge“. By this topology, a much better linearity and almost independence from ambient temperature was reached.
A basic circuit for the gas detector is very simple. A variable resistor serves to balance the bridge, i.e. for a zero output voltage in environment free of combustible gases. Power supply is 3.0V/175mA.
Prevent a gas explosion by means of the Figaro TGS6812 sensor - [Link]
A little over a year ago, I started playing around with the newly available AVR ATTiny4313. It’s a neat little chip, and you can have a lot of fun with it. However, I soon got tired of wiring up programming headers, power supplies and all the other stuff you need to get up and running. I also grew wary of all this support circuitry taking up significant breadboard real estate.
To eliminate all that hassle, I created the BB313. It’s got all the stuff you need (programming header, regulated 5V power, etc.) wrapped up in a nice little package, and it plugs in on the edge of the breadboard so you have lots of space for other stuff. I also added an 6-pin connector for an FTDI cable or adapter.
I originally designed it for myself, but I figured other people might like it too, so I’m releasing it open-source CC-BY-SA 3.0) so you can make your own.
All the details and source files are at the project page. If you find it useful, please let me know!
BB313: A Breadboarding Platform for the ATTiny2313/4313 - [Link]