Measuring AC Current with Arduino

[@neoc03]

Thanks you so much for posting this. The RMS code at the end is what I've been needing.

[@bostonmechanical744]

This works really well Had 2 add 2 4.7uf caps to a0 and a1 to gnd to stabilize readings tweaked factor to dial it in and scales through the range. tested on 5amp sct013 and 20 sct013

[@michalch1009]

For those who are confused by the multilier (LSB Size), here is how to calculate it for both ADS1x15: multiplier = Gain voltage / 2^(bits−1) For the ADS1115, the FSR (Gain voltage) can be set to 6.144 V, 4.096 V, 2.048 V, 1.024 V, 0.512 V, or 0.256 V. The LSB size is calculated by dividing the FSR by 2^15 (since the ADS1115 is a 16-bit ADC, but the 16th bit is a sign bit, for ADS1015 it will be 12-bit - 1). Here are the LSB sizes for each FSR setting of ADS1115: 6.144 V: 0.000188 4.096 V: 0.000125 2.048 V: 0.0000625 1.024 V: 0.00003125 0.512 V: 0.000015625 0.256 V: 0.0000078125

[@mumbucorporation7243]

Hi, thanks for sharing your knowledge, it helped me a lot. Could you please tell, how one can recognize which split core current transformer does have a burden resistor built in and which one doesn't?

[@Hangs4Fun]

I get your use of the ADC1115, and I do like that option if I ever needed the accuracy. I'm just building a servo ball valve for a dust collection system I'm making, and simply need to know if the machine has turned on or not. If it is turned on, then I would activate the series of states to put the servo's in (aka what sequence of opening and closing the various servo powered ball valves, aka "efficient blast gate"). In this scenario, what is the best way to run 12 or so of the voltage from these CT's straight into the Arduino? I currently have momentary switches for each machine, that I just push the button to activate that buttons sequence, and for the switch, I just run them into the pwm pins 2-13 (I'm using an actual pwm module, a PCA9685 variant with separate switched power to power and control all of the servo's). Would each of these CT's go into one of the Analog ports or one of the digital ports (pwm), or can this not be done? Too bad they don't just have a board that accepts 16 separate inputs and then just uses the clock and data ports like the 9685 does. Otherwise, it is looking like I will need to get at least one of these ADC1115 modules per every 2 CT (or 6-7 of them in total).

[@martinparker9044]

As it’s communication is via i2C you could use it on a Raspberry Pi too

[@rcstl8815]

Only rich people could in 2023.

[@jazekerxx7535]

how can you measure the direction of the ac current? i would like to use it to measure if i'm using from the grid or delivering back to the grid on sunny days (solar panels).

[@theairstig9164]

There is an answer that shows how but it depends on the audience having an understanding of electrical engineering. Something like the myEnergi harvi is designed to measure current and direction then convert it to OCPP or serial data. When a device is drawing current, the current is the same as voltage in the direction of consumption. When a device is powering a load the current travels in the opposite direction. So if your house is pulling from solar and the grid then the current will be towards your house in both cases. If your solar is powering the street, then the current from the inverter will be (out) negative and so will the current to your house. The current transformers (CTs) will show this clearly. If solar is exporting then the solar CT and the street CT will show (nearly) the same current. Same RMS value

[@michaelkimani4207]

Why do you use a multiplier value of 0.00005? I think you should use (0.00003125) since we are using ADS1115 and not ADS1015.

[@galagomara3611]

I think the answer is here: learn.adafruit.com/adafruit-4-channel-adc-breakouts/arduino-code

[@jokerbot2676]

I agree in ADS1X15 example they also suggest ....3125 for ADS1115

[@geraldgilbert9390]

The multiplier is the inverse of the GAIN. For Gain_Four it's 0.0005

[@duglmac]

Excellent video. I have this working with an uno r3 arduino and a sct013-030 attached to an ads1115. I also have an oled on a different pair of i2c lines.

[@user-bj4lp3fr1o]

I don't understand the "multiplier" of .00005. Does "ads.readADC_Differential_0_1()" read in bits and this converts bits to volts?

[@petittoto7433]

Hello, I don't understand why it works, the value is completely wrong, but my goal is to compare the consumption of my freezer when it works normally and when it doesn't (too much consumption for example when the door is no correctly closed and not enough if the motor has a problem). So I can detect a problem before the temperature drops. So thank you 🙂 PS : the Adafruit_ADS1X15.h calls for the library Adafruit_I2CDevice.h. If you don't have the second, you may have an error compilation error.

[@stormbytes]

SDA + SCL is IC2 not SPY. Really good video btw.

[@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???

[@LarryGuinta]

Well done video! I am building a demand controller for my Phoenix-based home. I am new to Arduino and have been struggling with getting it to read a current transformer. Your video was, simple and straightforward. I copied the software and everything came alive 1st time. My question is my current transformers are installed on L1 & Line 2 immediately after the primary 200 A breaker. They are 100/5 (100-amp primary with 5-amp secondary). I therefore changed line 7 "FACTOR" from 20 to 100. I am measuring the current on my 5-ton AC unit which draws 16.5 A @ 239 volts. My reading from the software shows 3.9 Amps and should be about 4 times that. Can you recommend the best way I should adjust the calibration within the software?

[@misperry]

Hey there. Glad the videos helped out. Now let me ask you a question does the ct you are using have a burden resistor?

[@brad4571]

Great video. Really good job explaining this from a high level down to actual hardware and software details.

[@3xAudio]

thanks. helping me improve my own projects and come up with new ideas

[@JeffZiegler76]

Thanks. Being SCT-013-000 is for 100A, what happens if it goes over? does it melt? I actually don't care about the actual value, just if current > 0.0 amp, we have power. Or would you try to measure the 220v?

[@hnag1907]

Hi thanks for a very informative video. If the voltage across the 20A current transformer is 0.5V ac can you say that the current flowing is 10A?

[@jokerbot2676]

Yes if you have 20A/1V version

[@spanyolnauli4839]

Awesome, How do we connected Current transformer (CT) more than two unit, for example until 40 CT to arduino? please give me your solution, thanks

[@MrPaulyoutoobing]

Thanks for this. Definitely helped me out.

[@electrical807]

Hello , Great little video thanks for sharing. I’m just doing a similar thing and would like to know if your setup works down to really low current? Say 40mA 5 watts at your voltage?

[@Dixitkushagra175]

It wont.

[@mIkeyGermita]

if you watch the video he explains how there are different models of current transformers for measuring different currents...

[@yung-ihuang226]

HI~ the multiplier in your code should be 0.0005, right? It's 0.00005 now. I am a little bit confused.

[@jokerbot2676]

Yes you are right. You can use 0.0005 as a multiplier but you have to unquote the "current /= 1000.0;" line. Also if you are using ADS1115 i believe multiplier should be 0.03125

[@TheRajeev7778]

Thanks for the post and detailed explanation,Can you please post idea of energy meter based on Arduino/ESP32 ?

[@mIkeyGermita]

lolwhat what is 'idea of energy meter'? how about you post idea of energy meter and we'll all come watch it @Rajeev How does it feel to be asked to do someone else's work?

[@TheRajeev7778]

@@mIkeyGermita thanks much for the advice,that was very helpful

[@ahmetnumankarahan8957]

thx again but i'll do this with sct013 for 100A and the rated output is 50mA. So can i use it by doing the same thing like using ads1x15

[@yousaftoki1599]

Amazing project sir..

[@bagusdwi6215]

Do u really connect 1 volt ac output from sct013 to ads1115 ?

[@misperry]

Yes, it is fine. The ADS1115 can take inputs up to VDD + 0.3 and max VDD is 7 so it can take 7.3 maximum. So if you take 1Vrms and divide it by sqrt(2) to get the peak it is only like 1.5V max so you are good to go on that.

[@fritzdaledelossantos8328]

Hello! I tried the code and I installed the ads1x15 library but I get an error saying "Compilation error: Adafruit_ADS1015.h: No such file or directory". Please can anyone help me I use the arduino IDE 2.0.5 version

[@aslPlayer]

If I need to measure the current from a 240 VAC single phase line, do I just use one of these on each hot line? Can I hook it to just one hot line and double the value? Or put one around all the wires?

[@johnmacgregor1464]

CT transformer should only go around 1 wire, and for 240 VAC single phase just need one CT transformer on one of the 2 wires, black or red.

[@muzammilbathi6483]

Is normal plcs CT are also used as same procedure with controller i have 150/5Amp puma company CT .?

[@misperry]

Did you mean 150A/5mA? If so you can use the same procedure but you need to supply a 200ohm burden resistor to scale the 5mA out put to a 1V output

[@farayolaahmed6462]

hi i am trying to build a current measurement to measure current from say 10amp to 800amp it to be used on transformers that draw up to 800amps please assist.

[@theairstig9164]

Buy a fluke 289 hand held CT clamp

[@coreyashford9905]

Anyone know if the wire used for that CT is rated for use inside a main panel?

[@muhammadtahakhan1649]

I'm doing alright thanks for asking

[@vetkangalae7606]

Thanx. I want to add this code to the role so it triggers the role when it's 10 amps

[@ronw.3115]

I tried your code unsuccessfully. Then thought why all the root mean square math when peek is easier to get the x .707 = RMS but when I took the max from the 1 sec worth of readings I actually got the same value as my meter (fluke RMS) no need to x .707 weird but is working extremely well for me (current measured within 5%, tested with 2 clamp meters)

[@nickfunk5804]

I am a little confused. The ADS1115 has an absolute maximum input range is -0.3V to Vdd+0.3V. With your schematic, the 1VAC will exceed the -0.3v input on the negative cycle. Wouldn't this destroy the ADS1115?

[@sspence65]

the ADS1115 can read 0v to VDD + 0.3v, VDD can be 2-5v. On my ESP32, VDD is 3.3v, so 3.6v is max signal input. a voltage divider of two 100k resistors will provide a -2.5v - 0v - +2.5v swing.

[@Shubham-9996]

@@sspence65 have you built current sensor

[@sspence65]

@@Shubham-9996 I've built many over the years.

[@Shubham-9996]

@@sspence65 Can you please suggest any website where I can find best circuit I want to build industry level power measuring instruments like Electric metre attached in domestic

[@OcenaSoft]

Am I correct in thinking that having 240v 50Hz here in the UK will not make any real difference to the code etc???

[@misperry]

yes it should be just fine. The core I think is rated at 150kHz so you should not saturate and it is measuring the current not the voltage. Thus, it should work fine. Now if you are wanting to compute power then you will need the voltage in your calculation.

[@OcenaSoft]

misperry thanks for the reply. It did work but, the results were up and down constantly and regardless of the current being drawn (unless zero). When I plotted the numbers it looked like a sine wave - is there a method to smooth this out? I was drawing 1 amp according to my scope but this setup indicated .910 and .019 constantly??? Any ideas?

[@rickfordgarrett2535]

Hey can you find help me with the switch configuration for LT spice . I have two switch in a circuit. I would like one open after 50s of charging a capacitor then at the same instant that opens I would like the other to close ( that was previously opened) for another 50 seconds. Thank you

[@mIkeyGermita]

Bruh I had to pay $60/hr to get help with electrical engineering. Good luck getting it for free!!

[@noambaum00]

how do i connect many sensord?

[@nicholascalla125]

how do you go about doing the physical connections?

[@misperry]

for this you will have to be very careful. I would recommend having an electrician help with connecting the CT's to the wires in your panel board. The CT simply clips around the wire and measures the current through it.

[@TheAlexdj1971]

Hi !!, is there a way to connect this non invasive sensor to Sonoff PowR2?

[@mIkeyGermita]

if your 'Sonoff PowR2' is I2C enabled or if it has an ADC, then yes there's definitely a way but 99.999999999% chance the answer is no.

[@92IslamicStudio]

great video. can you pls work on energy monitoring shield with arduino for curent monitorig using CT

[@sebastienperez8474]

Hello and thank you for this video. Is it possible to know the current way (+ or -) with this clamp ?

[@Mr31Vince]

its AC, so its both

[@daniloliaci2417]

How to connect the CT with Jack 3.5 to breadboard?

[@mIkeyGermita]

much smarter to solder, but you could search for a female 3.5mm jack breakout and buy that, that's what you're looking for and it's available for purchase

[@soufelectronicsandengineer7472]

Thanks dear friend for the video, the code that you used, does it measure the true RMS, or just you supposed that the wave is purely sinusoidal, and you use max and you divided by sqrt(2)? As you know, true RMS depends on the wave frequency

[@AlessioSangalli]

RMS value depends on frequency? Source of this claim? It doesn't make any sense

[@MrPaulyoutoobing]

The loop takes readings for 1 second right....which is causing an issue with my Ethernet in the project it seems. If I shorten that to 500Ms everything works ok Ethernet wise...have you tried messing with that timing? Figure it will work ok?

[@MrPaulyoutoobing]

I guess what I mean is, will less samples affect the accuracy?

[@samiabouddahab2]

could you help me! i wanna to measure the current, and the phase between it and tension for measuring reactive power

[@mIkeyGermita]

No one's going to help you for free. What world do you live in where someone with this kind of knowledge has time to be helping people for free??

[@samiabouddahab2]

morocco 😊

[@DiyintheGhetto]

Hey There awesome video, Looks good. But now here is the trick trying to do this without that breakout board. What would you need? Oh and I'm first haha i had to say it haha

[@misperry]

Hey hey thanks for the comment. Yeah you can do it with the built in arduino adc but you would have to first correct the AC waveform using a bidriectional circuit or if you can get a low loss rectivfier so you can get it to a form of 0V to 1V then scale that accross the 10bit internal ADC. However, that is quite lossy and you only have 10bit resolution. That was why I chose to use the ADS1115 so you could get more resolution and you can input the bidirectional voltage from the CD without any lossy circuitry in the way.

[@Top-notchShorts]

Great video

[@ShadowsNetworkbd]

How can i measuring load current of 3 phase ?

[@misperry]

simply enough if you just set three of these CT measurements. Now you need to remember you power calculations and depending on how the system is connected, delta or wye, the relationship between phase and line to line measurement may differ by sqrt(3). So in Delta connected the current will differ: Iline = Iphase *sqrt(3) in a wye connected system Iline = Iphase. And also remember if the source and load are different (i.e. delta - wye or wye-delta) there will be a 30deg phase shift accordingly. Hope this helps.

[@galagomara3611]

Thank you very much for this informative video. I have a question: why did you choose GAIN_FOUR and not GAIN_TWO or GAIN_EIGHT?

[@jokerbot2676]

Because maximum V output is 1 V. In this case GAIN_FOUR provides most accuracy

[@brendenadamczak9283]

More accuracy because the ADC is looking for a range of 5 volts. So it adds a 4 gain to take the 1V closer to 5v.

[@haziqiqbalhussain]

Thanks for the great explanation! Quick Question: Shouldn't the multiplier be 0.00003125 instead of 0.00005? I just checked Adafruit example sketches and it says 1 bit = 0.5 mV in ADS1015 and 1bit = 0.0312mv in ADS1115. Since you've used ADS1115, 1 bit in volts will be 0.00003125 . Could anyone please confirm this

[@jasonjohnson8489]

You are correct, and that should also fix the drift at higher amperages he was seeing in the video. I also added a 10K pull down resistor A0 of the ADS1115 to GND to remove noise and allow the reading to go to zero when there is no current flow.

[@jasonjohnson8489]

also, the ADS library may have changed since this was published. The correct library to add is #include not the one in the code on the hub.

[@yousaftoki1599]

Circuit diagramme shows ...please

[@ranahassankhalid6399]

hi thank you for the great explanation, but one question do i just need to change the factor to 100 while using the 100 amp version of this sct clamp and add a burden resistor? thanks...

[@michaelpatterson1096]

Good question. Rather than giving us the answer, I'd like to know how to go figure it out on my own. What do I need to read.

[@omemanti]

Like the video, still trying to get a stable reading, when I hook it up to a heater (2000W), it jumps in a couple of seconds to 4000Watts to 500Watts and somewhere in between during readings. what is the best way of getting stable readings? (maybe its because of my ESP32). I got an SCT013 hooked up to an ADS1115 and plucked your code from Github. And living in the Netherlands so, I'm using 230 to calculate the watts.

[@agustinguzman6375]

No. No. wait a minute: when you were actually taking measurements in the 13A range, your values were jumping around. Your Fluke meter, was not. it had a steady measurement. Why was this the case? are you able to dig deeper and figure out why the current measurements on the Arduino jump around like that?

[@ranjanpal7217]

Amazing Explanation...Just a query....As shown in video time (8:05) We need to cut SCT sensor in order to join the two wires to A0 and A1 pin. Is there any other possibility of joining this to Arduino GPIO pins, other then cutting the wire?

[@mesquitamk1681]

Cool very good your work would you have a video similar to my project? I have a screwdriver project where I use Arduino mini or attiny85. and SSD1306 mini LED display. with ACS758 50-or-200A module. of amperage. with an H Bridge and 4 touch button 2 to increase and decrease the amperage that the engine will be turned off. and 2 button to turn the motor to the left and to the right so the screwdriver will not blow the screw .... which I will tighten, be it small or large ... for arduino I only know how to write the code. since already thank you >>>>>>> suddenly it's a suggestion for a new video

[@sarowell]

ADR = address

[@dekipet]

In this video, you covered SCT013-020 CT which can measure Voltage. You mentioned SCT013-000 which measures Amps only, but you didn't cover it. There are differences. Not small at all. Besides SCT013-000 needs a Burden resistor, but the one you use in your video has built-in so you don't need external.

[@sspence65]

No SCT013 measures voltage. They measure current only, by definition. They output a voltage corresponding to the amperage running through the wire being monitored.

[@dekipet]

@@sspence65 There is no SCT013, but SCT013-020, SCT013-000, etc.

[@sspence65]

@@dekipet the SCT013 is a series. The -xxx indicates rhe current rating. -020 is 20 Amp for instance. The CT stands for current transducer. My comment stands correct.

[@andytren9498]

SCT013-020 CT build-in Burden resister for measures voltage.

[@rubenhidalgocarrillo]

The ADS has 9 MILLISECONDS time conversion. If you wanna calculate RMS current, from a mobile charger, for example, you will read nothing. It is not easy read RMS current... If you use a Teensy, with a 20 microseconds time conversion, you'll be able to calculate that. I published that (in spanish....), the problematic is obvious. kzbin.info/aero/PLXo6hmhWYYBhG33Cock6weKh8J6ojneDm

[@udeepakavindu3759]

Can you do video about measuring power factor

[@gohan3243]

Direct current current

[@stormbytes]

Bit exponents start at zero, so a 10 bit ADC is actually 2^9 = 512 possibilities. A 16-bit ADC goes up toi 32,768.

[@AlessioSangalli]

What? A 10 bit ADC gives you 1024 values,

[@sharant1849]

Ads1115

[@MrBobWareham]

So this video is just for Guys then no gales that also do Arduino!!

[@davidstevens3355]

Why do you yanks have to tell us about your day or your hat, just get to the point and move on.

[@anaghaautomation5724]

Too Complicated

[@DJ-nw2ef]

Sorry to complain about an otherwise interesting and useful video, but is there any chance that you could learn to stop waving your hands right in front of the camera lens? For some people that is intensely distracting, and it conveys no useful information at all. Imagine how you would feel if you were talking to some stranger, and they kept waving their hands quickly and randomly about two inches in front of your eyes. You would hardly be able to pay attention to their words, because you would be flinching all the time. I'm not literally worried about a poke in the eye, but, as I say, some of us are intensely sensitive to moving images that feel visually too close to the viewer's eye. If you look at professional TV presenters, they almost always keep their hands very still, for just this reason, and you should do the same. Please.

[@TheUnofficialMaker]

picky picky

[@DJ-nw2ef]

@@TheUnofficialMaker No, I'm not picky. I spent a year on the ground in Vietnam, and I have a form of PTSD, which means that I am easily distracted by such things. Moreover, I brought up the point in very polite fashion, on the assumption that the presenter - not you, evidently - would be sincerely interested in suggestions on how to improve his videos. You, on the other hand, seem to believe that other people's problems don't really exist, and all I can really say about that is good luck getting along with the human beings in the crowd. However, having survived a full-blown war, I'm pretty sure that I will survive both this video and your clueless comment. Finally, I see that your channel has a whopping two subscribers, and somehow I'm not surprised.