MaKoMo wrote:I installed a Phidgets 1136 last summer to measure airflow in my Probat LG3 on the exhaust. That setup still works as expected and I got informed that at least two others followed me and got this working as well on larger machines. I know that Morten in Denmark uses that same sensor, but is measuring the pressure in the roasting drum with similar results.

The main problem is that this sensor is not able to stand the high temperatures of the coffee roasting air. The trick is to connect the sensor not directly, but via some small brass tube and a short flexible tube connector. That way, the temperature of the air pressure at the sensor location is within its normal operating conditions. Further, I pointed the brass tube in direction of the airflow, measuring negative pressure (relative to the second pressure input of that differential sensor that I left alone at ambient pressure. That way I avoid that this measuring tube gets clogged by chaff or other particles in the exhaust air. Note that you need to ensure to properly bend that tube and not to fold it. I used a specific bending tool (see the pics below).

That Phidgets 1136 can be connected to Artisan via the general IO Phidgets 1018 or an SBC or any other Phidgets IO component supporting analog inputs.

Hope that the pictures below give you an idea of that setup,
Marko

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