Gas Sensor Module use procedure

Archive
1

I am testing my Gas Sensor Module.
But I don’t know what the produce is.
The Help tell me I need to SetHeatingElement (System.Boolean) first.
How long do I need to set the SetHeatingElement to true then read the voltage?
What is the safety heating time? 8 hours or less?

Below is my procedure, I am not sure it wrong or right?

Plan A

  1. Set the SetHeatingElement true.
  2. Waiting for 60 seconds for heating.
  3. Read the voltage per 60 seconds.
  4. After 1 hour reading then SetHeatingElement false.
  5. Waing for 60 seconds cooling then repeat to step1.

Plan B

  1. Set the SetHeatingElement true for 20 seconds for heating.
  2. Read the voltage
  3. Set the SetHeatingElement false for 20 seconds for cooling.
  4. Repeat to step 1

Any suggestion ?

Thank you

2

20 seconds should be enough but can read values and see when does it stabilize. Note that every sensor is different.

3

20 seconds is good, however it is recommended that you have a burn in period for new sensors to burn off any impurities from manufacturing. I’ve seen some people say leave it on for 24 hours and I’ve tried that without any ill effects here.

In my sample project I had the pre-heat on for 20 seconds, took a reading and then turned the heater off and repeated the cycle x seconds later.

so say timer1 = 60 seconds
timer2 = 20 seconds (preheat time)

timer1.tick would turn on the heaters and start timer2

timer2.tick would grab a reading, turn off the heaters and stop timer2

Now I did try experimenting with some of the sensors which required a lower heater voltage (really meaning lower temp) by using a shorten heater cycle, but I’m not betting the farm on the results.

4

Thank you Duke, I have bought a MQ-7 sensor board in china wensite. Cheap
Don’t get it already for testing.

5

Ok so the MQ3 included witht the gas sense module is sensitive to Alcohol, Ethanol, smoke.
How do you know what is being sensed? is there a way to tell or is it just sensitive to those types and all ove them change the read voltage the same?

6

yep

7

Hahah thought so