Zanduino / INA

Combined Arduino library for reading multiple INA2xx power monitor devices
GNU General Public License v3.0
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Shunt voltage of 0.2mV when there's no load #93

Open flambert2 opened 2 years ago

flambert2 commented 2 years ago

Expected Behavior

I would expect the output to be near 0 when there's no load connected.

Actual Behavior

I get a shunt voltage of 0.20000 mV and around 3500mW when no load is present. also it seems that the resolution does not quite fit, I only see steps per 0.02mV I would expect around 0.009mV since I have a shunt of 75mV 100Amp.

Steps to Reproduce the Problem

get a 75mV 100Amp shunt, remove existing shunt resistor on ina3221 (CH1), connect the external shunt, connect the esp to the ina3221. use the DisplayReadings example set these values: const uint32_t SHUNT_MICRO_OHM{750}; ///< Shunt resistance in Micro-Ohm, e.g. 100000 is 0.1 Ohm const uint16_t MAXIMUM_AMPS{100}; ///< Max expected amps, clamped from 1A to a max of 1022A

open serial console.