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- Check for continuity between 12 V, ISO12 V, GND, ISO GND, and 5 V (all of these should be isolated from each other).
- The board can now be powered by connecting a power supply set to 12 V between 12 V and GND. A current limit of 20 mA should be sufficient.
- Measure the voltage between the isolated 12 V and ISO GND, and 5 V and ISO GND.
- Turn off the power supply.
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