Hi davidlr, The values read from the BMM150 solely depend on the environment it is in. Typically, it will be a sum of the Earth's magnetic field and the other Soft and Hard iron components in your system, like speakers, magnetic locks, screws etc. in short, the magnetometer's environment and orientation. Modeling this can be done by reading a stream of values from multiple devices you know to be working at the point of test and creating a spread so as to not detect a working device as faulty. This will have to be replicated for each production line. If I hear about how most of our customer's tackle the same issue, I will post the solution here. Grüße, kgoveas
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