G+_Rud Dog Posted December 14, 2018 Share Posted December 14, 2018 This project: My new project which is Nodemcu, SCt-13 is working Got pretty involved and thought an update was needed in case anyone wants to duplicate. The first Gotcha appeared today. For some reason, the current no longer settles down to around zero. I had an IF statement allowing this to be covered at startup or reset. The results were good enough to move forward. Then today numbers nowhere near zero starting showing up on the serial monitor section. I have managed to work around this by adjusting thresh hold levels for zero and above voltages. These strange voltage reading are present via my code even when the current clamp is not connected to the wire. Just plain odd. Not a game stopper so will continue on. Link to comment Share on other sites More sharing options...
G+_John Sullivan Posted December 15, 2018 Share Posted December 15, 2018 Not really. I Googled for that problem when I couldn't get my numbers to stay low. One responder said it is inherent in the Arduino/NodeMCU, in that it is just not that good of an analog to digital converter ... it's just too "noisy" internally. Not sure if that is the best answer, but it seems to be true. Even with no input device connected, I get numbers that are too high to be considered "no current " Link to comment Share on other sites More sharing options...
G+_Rud Dog Posted December 15, 2018 Author Share Posted December 15, 2018 John Sullivan Learned something new. Have heard conversations concerning noise when it comes to ADCs also have heard comments on the resolution of ADCs. This real-world application and the noise causing me false reading is a great learning experience. For now, I can adjust the zero and max current readings to bypass false triggering. But in the near future, I would like to take the analog signal and see how it fairs using a less noisy ADC. Thanks again, John. Link to comment Share on other sites More sharing options...
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