I’m using the circuit from the Learn/Current Only Arduino Energy monitoring page, but using an ESP8266 board
I have an SCT013-030 so I’m not including the burden resistor (its builtin to the SCT013-030)
I am driving a voltage divider from the 5V Vcc on the board with the 10uf capacitor and I have the 10K and 2.5K resistors to bring the reference voltage to 1v
I initilize the emon with
emon1.current(A0, 30.1); // Current: input pin, calibration.
and calculate IRMS with a 20 second delay in between readings
double current = emon1.calcIrms(1480); // Calculate Irms only
I expected to see low readings (0.02, 0.06 etc) when the washer is off, and higher readins (0.5, 0.8 etc.) when the washer is filling.
I get the expected readings when the machine is filling, but I get various readings when the machine is off.
Sometimes the readings are low as I thought they would be; other times they are higher - identical to what I see when its filling.
I monitored and logged data all day (without doing laundry) and it will read low (0.02, 0.04) for a few hours and then jump up to 0.6 0.8 0.5 even when the washer is not in use, then return to the low readings. This is making it impossible to tell when the washer actually starts.
Any ideas why I am seeing the higher reading when idle? Or is this expected behavior? I was going to take a series of readings and average this out in software, but that does not seem feasible (see the attached graphic)
I am powering the ESP8266 using the USB cable and an USB power block.
The block is plugged into the top half of the outlet and the washer is plugged into the lower half of the outlet.
This outlet is on a dedicated circuit breaker for the washer.
I tried using a couple different USB power blocks thinking maybe the first was noisy or having issues and not generating the 5V consistently but I’m getting the same results from different blocks.
A graph of the readings at idle and when the fill cycle was started (the red line indicate the point that the washer was started.)
Thank for any tips or suggestions!