I’m experimenting with Wemos D1 Mini and using it to read from two CT sensors. I just realized that by nature the sampling algorithm is kind of slow. I was able to change the ADS1015 rate to 3200/s and change its default read delay from 8 to 4ms, but the library still needs a fair amount of time to…

Ok the speed problem is now solved, the Adafruit library needs some serious work, I suggest people use GitHub - jrowberg/i2cdevlib: I2C device library collection for AVR/Arduino or other C++-based MCUs instead, it’ll let you adjust reading speed easily and has no constant delay implemented. The rel…

As you are measuring only 14 samples per cycle, you might need a different constant (not 1/1024) in the filter to maintain roughly the same time constant in seconds - or you might find that the ripple is more noticeable with the higher resolution of your ADC, so the original value remains sensible b…

Right now, I’m actually reading 1480 samples in 1032ms. One cycle here is 50Hz, 20ms ? Witch is 28 samples per cycles, but that exceeds the 860 max SPS of the ADS1115, so some values are probably returned twice. I’m not sure I understand what you suggest (ok, let’s face it, I don’t understand what …

[image] ybizeul: One cycle here is 50Hz, 20ms ? Nope. 60 Hz, 16.667 ms. [image] ybizeul: What would be a good replacement for the 1024 constant? That is the filter’s time constant. That’s a loose term, because it is related to sample rate, not time per se, which is why I suggested it …

Great idea, I’ll work on that. Isn’t it 50Hz in the U.S. ?

What about that Robert? Top is raw values, bottom is filteredI, as in : sampleI = ads.getConversion(true)*4096/3300; // Apply scale factor from reference 4096mV to 3300 mV #else sampleI = analogRead(inPinI); //Read in raw current signal #endif // Digital low pass filter extracts t…

Maybe it makes more sense presented that way, this is millisecond 2000 to 3000 [image] My interpretation is that given the relatively high values of filteredI, the calculations for the calibration value are no longer valid but I fail to understand the logic behind the original 60.60 value, that d…

[image] ybizeul: Isn’t it 50Hz in the U.S. ? No, the North American grid frequency is 60 Hertz.

One of the reasons that we changed from using a high pass filter - to remove the d.c. offset directly and used instead the low pass filter to obtain the value of the offset and then remove it by a simple subtraction (there, that’s answered the questions I set you in your other thread!) was it is ver…

So I understand now why offsetI is initialized to ADC_COUNT >> 1, which is the binary equivalent of ADC_COUNT / 2. All right, in the end, it means I just have to be patient, and looking at a bigger scale, I actually stabilize after 4s or so with a value of 1024. [image] I actually fixed the spre…

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