DIY ESP32 AC Power Meter (with Home Assistant/Automation Integration)

[@Asu01]

This is exactly what I need, thanks! Now I can monitor how much power I'm drawing from my neighbour's power grid and adjust my load so it won't make any suspicion.

[@greatscottlab]

Glad I could help!

[@Asu01]

I'm happy you glad, @@greatscottlab. Sorry for the late reply, my neighbour's Wi-Fi was down for a moment.

[@geetanshgautam]

Lmfao

[@prathambhat2803]

😂😂

[@galladeblade6001]

@@greatscottlab I think you didn't understand correctly. 😅

[@ZeroMass]

My Sunday morning is complete... Coffee and *GREAT SCOTT!!*

[@greatscottlab]

Enjoy!

[@POWERFPV2024]

I have learnt so many things by watching your video and again a big love from India ❤️❤️👍❤️❤️❤️❤️

[@Evgen-Evgen-Evgen]

Oh lucky you, it's sunday night for me((

[@SriTejaChilakapati]

@@Evgen-Evgen-Evgen Well, it's past midnight for me and I'm technically watching this on a monday 😅

[@kishoreksm8366]

It's 1.30am here..

[@shingGOLDmonkey224]

The circuit shown at 6:42 is a nice idea and definitely works in a pinch, but it's a serious source of error in your measurements and can easily DESTROY your expensive ESP32. Firstly it relies on the precision and drift of the offset voltage resistor divider, which is not insignificant as if you are using 5% resistors, your center voltage and thus powerline measurement could also be off by 5% (or around 16v at line level). Also at startup, before the 10uF capacitor charges to 1.65v, the input of the ADC swings negative, which can seriously damage some devices which don't have stringent input protection. Finally, if there is some fault in the line which causes the transformer to output a higher than expected voltage, this will exceed the power rail of the circuit and discharge straight into the ESP32. You want a circuit called a "Clamper" or "DC Restorer" which will fix your voltage above ground potential (protecting the ESP32 ADC) and allow you to take advantage of the full scale of the ADC input. This also saves on two precision resistors for the voltage divider, and a rail-to-rail buffer amplifier will tend to isolate the ESP32 from any voltages over the supply rails. With an output buffer you can also use a smaller capacitor value, with higher voltage rating and non-tantalum type for safety such as a ceramic disk capacitor. You can also safely add an external ADC if you want to increase your measurement accuracy substantially. (Just remember to sample the max voltage to calculate the zero crossing point for the AC signal, as there is no center offset voltage now) There is no fundamental difference between your expensive power meter and a circuit you can build at home, you just need to find all your sources of error and minimize them! :) Here is example circuit for reference tinyurl.com/y2aoed7z

[@JuanFlores-rj1he]

Cool!

[@compthing5656]

This needs to get pinned. Pretty good reply. Thanks for sharing info

[@xxcr4ckzzxx840]

Sick reply, thanks alot!

[@shingGOLDmonkey224]

​@@xristost68 Nice work, only problem is that during that settling time the negative analog voltage would still exceed absolute maximum specifications on popular ADCs like the ADS111x, so you should add a schottky diode from ground to the output to limit that negative swing in the startup :) And if you're using an expensive precision ADC like the AD7792, it only tolerates 30mV below the ground rail, so you would need more strict signal conditioning than just a schottky diode.

[@sirente9275]

This is cool. Do you have more info on the circuit? Function and how to choose the capacitor and resistor pls

[@AmplifierWorld]

What a great energy you delivered while saying " stay creative and see u next time"

[@jeffpkamp]

Some points from my experience building The same thing for my own home: if you can't find a 12-volt AC former, you can step down the voltage just using a standard voltage divider with 10 or 20 times the resistance on the upstream resistor (depending on if you're in the Europe or US). If you want it isolated, you can use a one-to-one speaker transformer, or they have potted transformers the one-to-one ratio specifically for this task. Also the ESP32 ADC has abysmal accuracy without some sort of filtering in software. I actually used an Arduino nano to measure the current on the two phases coming into my house (US) and pass that off to an ESP8266 to send to my server. The values I got out of this setup were within 0.1% of what the electric company said I used.

[@С-8КОМ]

this dude read my thought i wanted to do that exact thing

[@backdemoletor4654]

Yeah me too... It's impressing

[@iamaromalms24]

Absolutely Like KZbin algorithm 😂

[@TheAvdeevVladimir]

Same here, but I thought it will be not accurate.

[@nikgru4577]

Same here

[@LuckySingh-ob4bw]

And he made the cable tracker video right when I needed it

[@KevinDC5]

I actually just received my very first ESP8266 NodeMCU in the mail yesterday and have been pondering a project all night. Amazing that you post this today!🤘🏼🤘🏼

[@Felix-ve9hs]

I just installed Home Assistend on my Proxmox Server and was searching for a "smart" Power Meter I could use with it, perfect timing :D

[@rzdakira]

"Handy and shocking." A pun across two languages. I love it

[@AgentOffice]

What's it mean

[@BrianLough]

@@AgentOffice handi is german for phone (maybe specifically mobile phone), shocking cause it's both a shock/surprise but also cause electricity can shock you

[@hooblydoobly9125]

Urmom

[@hooblydoobly9125]

@@AgentOffice urmom

[@hooblydoobly9125]

@@BrianLough urmom

[@adityag.5372]

Hey! This video doesn't start with the word "recently" 😅😅

[@_BSG_]

Vah bhai vah

[@allbeit582]

ha ha

[@JoaoSilva-jr9ez]

Power meter: shows -43W real power Great Scott: "the power meter still works perfectly fine"

[@mewantsmash]

I think he has solar panels, but I was also confused by this

[@JoaoSilva-jr9ez]

@@mewantsmash hm, his solar panels pumping current into the grid with a power factor of -0.25? dunno about that, but my guess is that solar panels should present a PF as close to 1 as possible.

[@eDoc2020]

He probably just hooked up his sensor backwards.

[@dirklaubusch5659]

Das waren grad "Grundlagen der Elektrotechnik" (1.Semester) und "HM 1 " ( Höhere Mathematik I ) in 10 Minuten. Der Mann hats echt drauf ! :=)

[@DJ-Manuel]

I can reccomend shelly devices, most of them have power meter feature integrated, there are aswell a dedicated powermeter wit power clamps. Even 3-phase is available. And they can be integrated very useful 👍

[@Goni0121]

thanks man. I needed a tree phase monitor and this is a good, easy to install and simple solution.

[@naseernajibi2583]

Thankyou very much and deep heartedly thanks for providing such detailed analyses!!! You solved my e monitoring issue . I have made a complaint home IOT, comprised of many usefull functions, this was where i was stuck. You made it so easy to implement in my esp32 project for Arduino IOT ❤

[@asrithtechsys6954]

I have literally no idea what I'm watching But I still love his videos :)

[@nathantron]

Some of the new/Modern US home power meters actually have debug output ports. You can hook into those if you want, they are read only and not encrypted in any way. So this may be even easier to access the data.

[@DrGreenGiant]

I've recently done this myself, well similar. I wrote my own code in the IDF and used the SCT-013 current clamp so I could measure the whole house current. No touching of live wires needed since it's a clamp rather than pass through doughnut. Works very well but I am assuming voltage since I don't have an isolating transformer yet to measure it. That's the next upgrade!

[@JohnBoen]

I came on line to just now literally to search for someone who has done this project - nice timing :)

[@TheMechanicGamerVids]

Your channel is always a great place to watch some cool videos utilizing microcontrollers like the ESP32. It’s such a versatile controller to have around! I’ve used them for all sorts of things, I had one hosting an access point with a simple html interface to control a project I had made.

[@owenmcpro]

"which is handy and SHOCKING at the same time" me: i see what you did there

[@greatscottlab]

;-)

[@POWERFPV2024]

For your KZbin channel islands so many things a love ❤️❤️from India

[@RajendraBhattRajDa]

He pulled a little sneaky on ya

[@linorocha6319]

Also "handy" is cellphone in deutsch ;)

[@etmoimeme]

Could you explain, I don't get it?

[@galladeblade6001]

This is one element of my thesis paper on college. Those stressful days.

[@angzarr9584]

We need to get this man to 2 Million

[@ΔημήτρηςΚαφφάτος]

I had something like that in mind for a long time, great job!!! Adding a temperature sensor on a solar heater and a power relay we could remotely power on its internal resistor when we need it (without have it on all the time). We can also watch the power consumption for security reasons and be able to turn on the outside lights remotely, and so on. Home (and not only) automations with microcontrollers is so simple this days and we can do so many things that really worth spending some time learning how to program them which is pretty simple and a great way to learn children how and why programming is fun and why maths physics and chemistry is necessary most of the time on whatever we do :-)

[@rob_cek]

Im always so fascinated by your projects and even more how economical you make them even though you live in germany where gross can shoot up very high, keep up the spirit scott! (Im from slovakia, so you can understand the meaning of the comment)

[@briangitau7737]

Bmore

[@khayhensarveswarah5731]

The CT Clamp component in ESPHome is based of the emonlib library and has very easy integration, it even allows you to use a higher precision external ADC such as ADS1115.

[@solieeeeeee]

There is a simplier solution for power measuring which is called PZEM-004T (with great accuracy of measurements too!)

[@LanceMcCarthy]

I love how popular Home Assistant has become.

[@thetechboy8529]

I am waiting for this video for a long time. The most informative video on this topic on KZbin Thanks sir

[@nicholasbishop01]

We just did this for our EE senior design project back in the spring! We won first place!

[@floris00]

If you have a smart meter (which a lot of people have nowadays in Germany and the Netherlands) you can hook up a RPI to the P1 port of the meter. That port spits out a lot of info about your electricity and gas usage (if you have gas at your home). You can also integrate it very easy with Home Assistant.

[@didnotkn0]

Great video, I love incorporating tech into homes like this. I would also like to say thank you for making videos, you have been such a huge inspiration to me and a large reason why I want to get into electrical engineering, much love from Phoenix, AZ.

[@jiangxu3895]

I never thought so careful about this problem. Thanks Scott

[@mojo_jojo]

Wouldn't be one of the eastron meters an option? I use the sdm630 which is connected via modbus to a raspberry pi. The values can be published via mqtt.

[@brandonstevens6886]

"I have the goal of lowering mine though" Says the guy with a 3d printer, a cnc mill, and literally every high current device XD. Aside from that I really love your videos.

[@Private_Duck]

I really want to see that tesla coil. I've been watching your videos since i first started electronics about three years ago. I still cannot believe that you didnt make a tesla coil that can make some interesting arcs.

[@tomwilliam5118]

It's always nice to see the the face behind The Voice the videos I watch

[@damzelfly]

Now I need to figure out how to measure a 3 phase power which I use in my home now. Great video for me to get started. Thanks!!

[@petersage5157]

GreatScott! glosses over a summation formula that probably has most viewers' eyes glazing over. "And just like that..."

[@georgei2480]

I'm a big fan of making cool DIY projects that you cant already buy on the market. The issue I have with this project is that you can already buy a commercial version of this product that will be more reliable and cheaper than making it yourself. The Sonoff Pow can be bought for around USD 11, It has a built-in power consumption tracker, it has a built-in relay for remotely switching the appliance on and off, it is in a clear professional enclosed, and it can easily be modded to work with home assistant. Unfortunately, there is no reason to make your own. It will cost you just as much and you will have a lesser product.

[@diniitotoom2526]

this my favorite channel on youtube😍

[@Ke_Mis]

If you want to save energy, just turn off the light strip in the background (0:15), Scott! Jokes aside, great project!

[@1976kanthi]

Thank you for making excellent electronics videos. You are my favourite electronics KZbinr!!!

[@TheOrginalHumibold]

If you got one of the newer electricity meters just count the light pulses it emitts and calculate the power drawn

[@eDoc2020]

You can do that but it only gives an indication of power (actually energy), not the other parameters like power factor.

[@TheOrginalHumibold]

@@eDoc2020 that's true but that the most important thing to know in my opinion. Because that's what you pay for and if you are using this to monitor your power consumption that's all you need

[@MeisterQ]

I think your problems with such diffrent values is the non-linearity of the ESP32s ADC. There is alot of stuff about this on google. The best thing so monitor the values all the time is to use a Shelly 3EM and integrate it into your hass

[@05PAJA]

You are right, but the different price tag. Shelly3EM = 100€. if you calibrate precisely, the data are usable.

[@patrickjoseph9476]

Great Scott, love watching your videos! It improved my electronics knowledge by a ton!

[@DownToNerd]

I was going to ask you for a vid on what oscilloscope to buy for tinkering like you. Then i saw the part number on this vid and searched for the one you use, holy shyte, thats a 12000 euro oscilloscope. ok nevermind, i'm gonna keep using my multimeter like the noob i am. good vid btw, as always

[@alaanoor3679]

another GREAT video from GreatScott!

[@greatscottlab]

Glad you enjoyed it!

[@HemonDey]

Thanks for this video, I enjoy watching your channel and its great content. I've created an energy metering system in my house using existing energy meters with pulsed outputs, basically gives a pulse for each 1whr consumed - this significantly reduces the complexity of the project as it means only having to count pulses to get near instantaneous energy consumption values. Also if you also monitor milliseconds between pulses, you can work out near instantaneous power consumption as well. These meters are very common and easy to obtain, and they also by their nature have to be reasonably accurate - an added bonus is that they also typically come in a small form factor (1x din width), and pulses are isolated from mains. I populate the energy/power values directly into a time series database (Influx) and graph with results using Grafana.

[@jcdameoh3528]

My brain is overload but great video GreatScott

[@Od3o_ela_sabil_rabek]

06:42 what's this circuit please mention the name of this one

[@letenof]

The AC voltage is both positive and negative. ESP32 ADC input accepts only positive. The circuit adds a positive offset (half of 3.3V) so that negative voltage will never reach ESP32 and damage it.

[@greatscottlab]

It is a voltage divider.

[@Od3o_ela_sabil_rabek]

@@greatscottlab Ok Thank you for you're attention

[@maxk3673]

Nice Project but one thing strikes me about it. Is the RealPower supposed to be negative? @ 10:42

[@greatscottlab]

Yes

[@steefant]

@@greatscottlab can you please elaborate? is it another joke I didn't get? :)

[@raybright5805]

Great explanation of how different loads effect the phase angle between Voltage and Current BUT to keep things simple with respect to monitoring power consumption (as charged on your power authority account) have you considered just monitoring the pulsing LED on your power meter. I suggest this for one of your excellent KZbin videos.

[@theoneohmresistor]

now you can get similar thing for $8, and with a relay... great stuff

[@vishva8kumara]

I'm running two circuits, one with grid power supply only (high-power appliences) and another with fail-over from an inverter/battery that has low power appliences and all lamps. I also need to monitor battery charging and discharging currents with voltage, so I could measure efficiency and battery health. I think one current sensor would be enough on battery +ve terminal ; should give -ve values when charging and +ve when discharging.

[@rameshprakash3887]

Awesome bro.... This is from India... Vera level.... Thank you for the video...

[@RomanoPRODUCTION]

DIY wins again. Awesome GreatScott!

[@John_Ridley]

This is what I've been wanting to do, though A) I want to do every circuit so I need about 30 channels of sampling, and B) I don't really care that much about precise values, calculating reactive power, getting RMS values, etc. I just want some relative values so I know what circuits to go after as hogs next, or which can be adjusted to run primarily in the daytime when the solar panels are producing.

[@resources5166]

I had a doubt Scott, why dont you use ACS712- Current sensor and ZMPT101B- Voltage Sensor and make it as simple as possible and well portable as well with no external circuits as well?

[@korishan]

I have built one of these, but with an Arduino Nano. Works pretty good, though not very accurate, especially with low power usage. So I decided to go the Esp32 route. But the built-in ADC resolution is still too low. Which I went with an ADS1115, which gives me 16-bit resolution. Problem is, I can't get the ADC to properly work with the EmonLib code. I've even done the procedure injection, or what ever it's called and made the changes for it. Still nothing. And the guy who originally made the altered code for the ADS1115 with EmonLib won't help. Any ideas on how to get these to work together? I know the ADS1115 can only do about 800sps. To get "real" power consumption, need at least 1500sps or something like that. But it'd be better than the built-in ADC. Also to note, the standard EmonLib can only do about 4 return values per second, and this is because it does several loops per run to get the values. This does slow down the returning values quite a bit.

[@matiastripaldi406]

Great vid as always! Just one question, if you used a current transformer that supports up to 5A how are you going to measure the power for your whole house with it? Surely the house draws more than 5A and that could destroy the transformer

[@eDoc2020]

It looks like he was just measuring a single circuit. Plus I don't think it would destroy the transformer, it would just give incorrect readings.

[@BenCos2018]

It can destroy the transformer if you put more than 5 through it I think You can just get a larger amperage one though to measure larger circuits tbh

[@BenCos2018]

@@eDoc2020 he was only measuring one circuit

[@RanjeetSingh-nr5sg]

Please suggest how to choose or decide the calibration value to get the right readings.

[@MegaTeXHaPb]

Hi, friend! I want to notice 1 point. If you place information wires along with the power wires you can get some extra power in case of quick power jumps. Once we tried it on GSM equipment and had to pay 1000 euro for broken input modules ;-). So think about electromagnetic shield.

[@andrewkieran8942]

I'd like to hear more about the circuit at 6:40 that scales the AC voltage and shifts it to be above the ground reference used by the ADC.

[@greatscottlab]

It is a voltage divider. Nothing more.

[@andrewkieran8942]

@Kevin Counihan Thanks. I understand the resistor values, but what about the cap? Why 10uf?

[@andrewkieran8942]

@Kevin Counihan Thank you! That's very helpful.

[@blackbird8982]

What about using an optocoupler as a reference point for timing?(zero voltage detector as an interrupt)

[@vaibhavbhasin3861]

Its super cool , but its really difficult when you start. For beginners point of view, various topics like working of esp32, how data came into mobile app, current sensor calibration etc are alot of things to learn. 🤖 All the best to all and do share your experiences. 👍

[@nagybogoslofasz]

There are meters that provide these values and are more compact, possibly more precise and reasonably priced. You could even read then with the cheapest arduino

[@MagSun]

8:40 how do you calibrate these values? Do you need a 1000€ power meter to find the right values? 😱

[@05PAJA]

No, you dont need power meter. Just a good multimeter and calibrate the voltage and current values to get match with the value's output on IDE serial monitor.

[@TuncayAyhan]

Home-Assistant again! Nice video Scott!

[@edwardvanhazendonk]

Thanks again, great explanation of a rather complex setup in a short period of time.

[@АлексейЕрошкин-ш9ш]

This video is cool as educational stuff, but in reality it's much easier, accurate and maybe even cheaper to buy something like sonoff pow r2 (not an ad, just an example) smart relay with all this measuring functions included.

[@PiyushNikam]

You must have used a more generalized component for stepping down the voltage similar to the CT

[@bbascyber]

@10:41 -42.78W and power factor -0.25! What was the load?

[@raffaelepignataro738]

I ended up on this video because I'm doing the same in my house. I did a lot easier approach without using an external library but just using the CT-clamp esphome sensors support. My issue is that I have an approximate power value since I have no way to differentiate on the load type so everything is calculated as a power factor = 1 like a resistive load. I will make a better analysis on how to integrate the emon lib to have a better accuracy. Thanks

[@traditionrider]

Handy and shocking at the same time - funny😂

[@johnavonvincentius1884]

The more easier way is probably using the pzem-004T module with an esp-01...maybe a future project? :D

[@tfoutfou21000]

PZEM-016 is better in many aspect (many device on one single uart/bus , power factor report , 100A max , much much safer PCB design) i personnaly have 20 of them in my house :D

[@tfoutfou21000]

Personnaly i prefer the pzem. I dont want 20+ more device on my wireless network. And I prefer not to have the current passing thru the device , pzem use an external current transformer. Regarding price the pzem is cheaper by 20 to 50%. (9 USD in china)

[@tfoutfou21000]

@@Android-ng1wn The pzem 016 and pzem 014 Need only one Arduino (or any controler) And they output their own 5v to power the controller. They work on a bus and you Can have as many as 256 on a single uart. Currently is use mqtt to send data where i want 👍

[@SirHarrisonPhillips]

Great Scott is with us!!!

[@compubyte2010]

ok, you can see it on your phone,, that's cool.. .. a silly question . as it's for HA . can it be integrated into my display for HA?

[@sayantanmaiti2513]

I would suggest to use those Hilink 220v to 3.3v AC-Dc converter for directly run esp from mains

[@prathamkalgutkar7538]

It won't be Suitable here, Cause those Generate Stable 3.3V DC while here we need to Sample the AC Voltage which Fluctuate Constantly

[@sayantanmaiti2513]

@@prathamkalgutkar7538 i'm talking of supply to the esp

[@avejst]

Great video as always👍😀 Thanks for sharing👍😀

[@Gallardo6669]

I have a big rpm autometer lying around. I would like to hang it at the wall and watch the needle dancing once my amplifier sucks amps to produce a bass.... Would you like to make a video about such a project???

[@EhsanHabib]

That's what i needed ... Perfect Timing

[@AJBtheSuede]

Great construction :) Unfortunately, here in Sweden almost 2/3 of my energy bill is made out from static taxes and grid fees.... This would be ok in an apartment - but me and my GF live in a fairly big house of our own, where the main heating is electrical (deep ground heat exchangers to heating water circulation). If I cut my actual consumption of energy by 99%, my electricity bill would only go down by maybe 35% :(

[@misteragony]

Can someone explain why you need the voltage sensor? Isn't a current clamp enough?

[@greatscottlab]

Necessary for the power factor calculation.

[@misteragony]

@@greatscottlab Ok, thanks for the reply. I ask because I have been using Flukso for doing similar stuff only using current probes: www.flukso.net/. I have three phases at home, so I would need to install 3 voltage monitors.

[@TECHBUSTERNAMAN]

I wonder how accurately you make your projects ....

[@roedyhellyeah]

you also have a P1 port that you can use. and an Easton meter is not that expensive and MID certified

[@richardkuhne5054]

how about another project for a 24 or 48V system to measure current and voltage i.e from a battery

[@Aybex97]

Great video as always, But I have a question, would the transformer not influence the phase of the measured votlage? Wich will make the power factor and active power not precise . Or was that accounted for in the code ?

[@eDoc2020]

It would influence the signal, but as long as the transformer isn't tiny the effect should be negligible.

[@JuanoD_]

This is just what I needed. Just in time. As always, great job :D

[@swaroopcool22]

waiting for a video on "main electricity safety essentials". What care should be taken when handling AC 230 V

Hi! I tried this method but I ends up using the PZEM-004T or HLW8032. It shows more efficiency since I have one dedicated chip to measure the power and let the ESP32 to register and casting the data. The only problem that I found is that I don't know how to find if the power factor is capacitive or inductive. They just show me the power factor, without a positive or negative sign =/ Otherwise is perfect.

[@BILL1986able]

Did you consider using an ACS712? If yes why didn’t you use that to measure the current?

[@harshprajapati6851]

Hey can you help with how to use the CT coil of broken multimeter in this project

[@rattehalliravishankar1801]

Very nice idea. How can we get this product commercially.

[@marekklucka4407]

Hi Scott, you should definitely do a follow up and some finalization of this. I need to do exactly this, but the situation is that I want to see each of the info about consumption per beaker, so the question is, do I need to have ESP for each of the breaker? Or is there possibility to combine them? A lot of questions which I think you've been working on in the past, so your experience would come in handy. Thanks

[@MCsCreations]

Fantastic work, dude! And really interesting project! 😃 Stay safe and creative there! 🖖😊

[@bsand1746]

Your videos are awesome man. Please keep it up! Thank you

[@aazdu03]

I would have liked more explanation on your simple circuits and the choice of your components. For your offset circuit i understood the use of the decoupling capacitor and the voltage divider but i don't get the use of the 200ohm resistor and the inductor...

[@nunolourenco1532]

I have been doing this by reading the blinking led in the power meter. Also read the needle in my water meter but with less success (turns out that the water company doesn't like IR sensors to close to the meter...). Too bad they are outside (no power source ) and my domoticz was to be turned off. I'm now researching home assistant to reset these.

[@affehombula6840]

Hey, nice video, like always

[@vaibhavhayaran]

exactly what i needed thanks!!

[@greatscottlab]

You're welcome!