Solve most of your issues, ESP32

[alexmoz2016]

Some code that you may want to change to make it work (I have ESP32): In EmonLib.h:

    #if defined(__arm__)
    #define ADC_BITS    12
    #else
    #define ADC_BITS    10
    #endif

Just add/replace with: #define ADC_BITS 12

Because ESP32 is a 12-bit ADC.

In EmonLib.cpp Replace all occurences of "/1024" by "/(ADC_COUNTS>>1". The code was originally written for a 10-bit ADC, without ability to change it to 12 bits.

That's all. The precision and predictability of the reading is improved a lot.

Another note, for Calibration (111.1 value). If you have a voltage-output sensor (SCT-013-015, SCT-013-020, etc.), replace the "111.1" with "15" for -015, "20" for -020, etc. In other words, use the same calibration value as the Amp/V value (15A/V use "15", 30A/V use "30"). Most of the examples I saw online, using the 111.1 calibration value, are only good for SCT-013-000 with current output (which also require a burden/load resistor). Since the non-000 (-015, -020, -050, etc.) sensors have the burden/load resistors integrated, the calibration constant is different.

I hope it helps someone. Took me a few days to figure it out.

Alex

[alkaraschu]

"Replace all occurences of "/1024" by "/(ADC_COUNTS>>1"." Probably a bracket missing?

[DieWaldfee]

"Replace all occurences of "/1024" by "/(ADC_COUNTS>>1"." --> Error cause of missing ")" should be: "/1024" --> "/(ADC_COUNTS>>1)" (as @alkaraschu mentioned)

[staadecker]

If I'm not mistaken, you should really change all values of 1024 to ADC_COUNTS not (ADC_COUNTS >> 1). The former is equal to 4096 and the latter 2048. If you want to match the behavior of the original 1024 code, then 4096 is the correct value for a 12-bit device.

It doesn't matter too much though since these values are just for the low-pass filter and either 4096 or 2048 are likely large enough to work.

[peteDDD]

Note that the ESP32-S2 has a 13-bit ADC...