my methane detector is always fluctuating, waiting your help?



i have bought some Pyroelectric Detector and ir bulb from a
company, and made my infrared methane sensor.Now I had some problems
1 the data denotes the concentration of methane in our display is
changing in a short rang(about 700ppm).
the principle for the detecting is ndir.who can help me, waiting your
help urgently.

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