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    BM688 Heater Profile: Are they important?

    BSTRobin
    Community Moderator

    Re: BM688 Heater Profile: Are they important?

    Hello hhammer,

    It means to detect different kind of gas, it needs to do much lab test and generate profile.

    I suggest that if you design a project, you could refer current existed profile.

    hhammer
    Member

    Re: BM688 Heater Profile: Are they important?

    I understand that the gas resistance differs for different sensor temperatures (e.g. 220°C or 350°C), but this is no explaination why the order in which I measure at differente temperatures would affect the gas resistance.

    Lets say I want to find H2S:

    I measure gas resistance at 250°C, afterwards at 280°C and again at 330°C, each time I measure for 100ms. As a result I get 3 gas resistance values corresponding to the three temperatures, but in my understanding they are not connect in any way to each other. So it would not have any influence if I measure at 250, 280, 330 °C or  330, 250, 280 °C, except for I have to wait until the sensor has reachted its temperature.

    The meaning if the heater profile is therefore unclear to me and it seems like nobody can really explain what the order of temperatures would matter for the measured gas resistance. 

    Any specific hints are welcome!

     

    hhammer
    Member

    Re: BM688 Heater Profile: Are they important?

    Any ideas?

    BSTRobin
    Community Moderator

    Re: BM688 Heater Profile: Are they important?

    The resistance characteristics of different gases are different, and the corresponding profiles are different. Usually, the detection of a certain gas needs to be strictly tested in the laboratory. Otherwise, if the heating temperature is arbitrarily modified, the gas cannot be detected correctly.

    You can use current existing profile.

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