@@ -4,3 +4,7 @@ This is documentation for an energy monitoring device built around the nRF52832
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This device produces around 0.1 volts/amp out of the sensor (or ~1 mV per Watt through the plug). The nrf adc has a +-0.6V reference, 4x gain, and 12-bit conversion, which might resolve 100mW (maybe finer with oversampling). Certainly not precision measurement, but good enough for monitoring appliances.
The nRF52 radio+microcontroller draws 5mA in transmit and receive, so it could operate well within the specs of a coin cell, or harvest from the power line (say, using http://www.linear.com/product/LTC3588-1) to charge a capacitor for power.
