Sorry for really dumb question, but if I want to measure a resistor via ADC, I see that connection 6 (Green) has to be wired to GND_SENSOR. The question is -- how is that different from GRD in connection 2 (Black)? Thanks
ADC wiring
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- Shelly Uni
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James Barrett -
7. November 2023 um 02:15 -
Unerledigt
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Welcome to the forum, James!
To your question: As shown at the right of this sketch, the Shelly UNI contains a full-wave rectifier bridge:
Thus, the difference between pin 2 (GND) and pin 6 (GND SENSOR) is a diode, which causes a voltage drop of approximately 0,7V. Hence it is recommended to use pin 6 with a DC supply. Supply voltage has to be fed via pin 1 and 6. This ensures a stable ground reference potential.
