To test the current sensor an arduino, a multi-meter and a current source was used. To calibrate, the offset and the gain was first configured. With no current on the sense lines, the Vref was adjusted to read about 2.5V (actual valued used was 2.52V) on the sensor output line. A known current input Iref of 100 mA was passed through the input channels of the sensor and the output deflection was then set with the gain pot. The sensitivity was then calculated by (Vref – Vdeflect) / Iref. With a Vdeflect of 2.61 volts the sensitivity was found to be 0.9 V/A.

Using the current source a Current vs Voltage relationship was plotted  (see below) and a linear relationship between current input and voltage output was found as specified by the manufacturer.

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