Measure AC Voltage with ESP8266 12E + ZMPT101B | App Inventor | Adafruit IO MQTT

[@SurtrTech]

Hi, all what you need is in the links below the video, including the app ".apk" and its ".aia" files. Let me know if tutorials about Adafruit MQTT / MIT App Inventor are needed. Here are the video Timestamps: 0:00 General talk 2:53 First Code/Signal visualization 3:35 First calibration 5:45 The base code (Important for all future applications) 8:00 Second calibration (Slope and Intercept explication) 11:10 The base code in use 12:17 Adafruit IO MQTT Code 14:42 Adafruit IO MQTT Code in use 15:58 Code to use with local App Inventor App 17:23 Code to use with local App and the App in Test

[@udeepakavindu3759]

Can you make a video to measure power factor using the voltage and current waveform time shift

[@andre0baskin]

Should I see a relatively regular sine wave? The sine wave I am seeing is jagged at the top and bottom even after I have adjusted the sensor. The other thing is that my AC voltage is bouncing around over a 5v range when I measure it on the meter.

[@SurtrTech]

Hello, you should be able to see the shape pretty much like the video (I had sinewave), and it should look like your signal shape, the potentiometer gives you this ability just keep turning it while checking the signal shape. Sorry, I didn't understand the last part, where did you probe with the meter? Is it on the output of the sensor? It will give you wrong measure because there's an offset. Also I'm powering everything with 3.3VDC, so it will never exceed it, using 5V will damage your board.

[@andre0baskin]

@@SurtrTech Thanks, I'll keep at it with the potentiometer. As for the last part, I am referring to the incoming AC voltage. It is not a constant voltage but varies over about a 5v range like 185 to 190 for example.

[@SurtrTech]

@@andre0baskin Using the meter? Better use some good quality ones and makes sure they're TRMS, if using the sensor with ESP8266, it could have some calibration issues.

[@dafpnp]

Why does serial plotter start to show sine wave when keeping a minimum of 100 milli sec delay? If the delay is any lesser, sine wave is not shown.

[@SurtrTech]

It's just a matter of signals synchronization, the signal is 50Hz, it's pretty high to be displayed clearly at real time, adding a delay appeared to give a clear shape.

[@dafpnp]

@@SurtrTech right. I started from 10 ms delay and upto 95 ms. The waveform just remained the same jittery. Right at the inflection point of 100ms, it started to show sinusoidal wf.

[@dafpnp]

Can you do a video on filters.h I could tune the code and get the voltage levels correct, but I couldn't quite understand what the filter.h does. How does it find the RMS voltage?

[@SurtrTech]

If you want to know how the library works please check the filters library especially the "RunningStatistics.cpp" file, you'll find all the functions used to measure the RMS, it uses the "Sigma" and the "Average value", those are statistics stuff, you'll find courses about them... it's a bit long to explain.

[@pratikchaudhari9821]

How to Calibrations ZMCT103C current sensor

[@SurtrTech]

I used ACS712 before, the exact same thing as this, I don't know about ZMCT103C, you can always try.

[@pratikchaudhari9821]

@@SurtrTechhow to use ACS712 current sensor in 440V. It's working 440V

[@SurtrTech]

Better learn the difference between voltage and current before you proceed to any of this...

[@pratikchaudhari9821]

@@SurtrTech okay thank you.

[@impulse_ger]

Is there a module to measure up to 50v dc?

[@SurtrTech]

There are other sensors for the DC ... I think most of them work up to 30V, but you can add a voltage divider... This one won't work, it has a transformer at the input.