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Nothing but the truth - and what does Mr. Gauss have to do with it?
In many cases modern inclination sensors use the MEMS technology for it’s sensor elements. Repeatability and linearity is not the challenge - it is easy to calibrate. The main influence is the temperature. This is indicated as deviation of angle degree per degree Kelvin. Values like 0.01 deg/K look good but if you consider a +/-50 C° temperature working range, the result is an overall +/- 0.5 degree deviation. In many cases this value is indicated as ‘typical value’. Although the definition of typical varies, an example may +/- 1σ. This means that 68 % of the sensors have this characteristic.Standard_deviation_diagram.png But what about the other 32 %? Carl Friedrich Gauss gave us the answer. The maximum deviation of the sensor element is statistically valuated.
As you can see in the Gaussian distribution curve, 68 % is just about 1/3 of the real accuracy. Let’s say: a third of the full truth. If you cover all the sensors in this example, the real inaccuracy is considered 3 times higher. Manufactures of construction machines cannot be satisfied when they are only guaranteed that 68 % of their Machines will work within the specified range, can they?

This is why MOBA has established a temperature learning process. All of our temperature calibrated sensors are heated up to +85 C° and cooled down to -40°C. At these extremes they “learn” individual temperature characteristics and are able to correct themselves. This is verified with a second temperature test. If MOBA indicates the temperature accuracy, we are indicating the absolute value over the full quantity of sensors.

The accuracy of the temperature-compensated MOBA Sensors is 0.002 deg/K. The whole truth.
Boris_Zils 04.12.2015 0 1478
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