4.2.2 Isolar

Connect a power supply set to 12V to the solar input leads. This will bias the solar input voltage to allow the current sense to function correctly.

Acquire a second high-current capable power supply with an adjustable current limit and floating output (with respect to earth ground). Set the output voltage to a minimum (<2V typically) and the output current to a minimum. Enable power and short the output leads (not connected to the PCBA). Set the short-circuit current to the lowest value shown on the Calibrate tab (Figure 4-1). Disable the power supply output.

Now unshort the connections and apply them to the following terminals:

These connections will put the applied current directly across R17 which is the Vsolar input current sense resistor.

Enable the high-current power supply output and adjust the output (short-circuit) current to each of the three values shown, clicking the corresponding button in the GUI to capture the ADC counts for each value. Disable the supply after these three currents have been applied.