A2C-SG2-M12
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From Measurement to CAN value
From Figure 8 the flow of data is explained.
Once the signal is sampled the calibration constants are applied and from then on floating points are used. Min/Max/RMS
calculations are done after the FIR filter.
The ADC has 24 bits making the highest value 0xFFFFFF. The maximum voltage is limited by the excitation voltage and also by the
input buffer. See Table 1 for input ranges vs excitation and gain values.
In bipolar mode when the ADC inputs are shorted (0 input voltage), the ADC output is half the ADC range (0x80000). A negative
differential voltage will result in values between 0- 0x7FFFFF, and positive voltages between 0x80000-0xFFFFFF.
After sampling the calibration constants are applied. From the factory the result is calibrated in such a way that the minimum ADC
input results in -100, and maximum input = 100. This is useful in strain gauge and load cell applications as both tension and
compression are output with zero strain resulting in 0.
After calibration the FIR filter can be enabled. The Minimum/Maximum and RMS values are calculated afterwards. Before being sent
on the CAN Bus the integer scaling is applied.
Figure 8 – data flow
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