Arduino based current meter with i2c LCD screen

A simple current meter using the arduino. The schematic is for Arduino UNO/NANO and all the the breadboard tests are made using the NANO. For different scales I've used some push buttons to change between scales. There is also a bit of Ohm Law theory on the video and each part is explained.
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my Q&A page: electronoobs.com/eng_preguntas...
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-----------------LINKS-------------------
Current meter: www.electronoobs.com/eng_ardui...
See also:
Capacitance meter: electronoobs.com/eng_arduino_t...
Resistance meter: electronoobs.com/eng_arduino_t...
Current meter: electronoobs.com/eng_arduino_t...
Inductance meter: electronoobs.com/eng_arduino_t...
---------------MATERIAL---------------
10A75mV shunt: www.ebay.com/itm/75mV-DC-10-20...
LM324 Op-Amp: www.ebay.com/itm/10PCS-LM324N-...
AD623 instr Amp: www.ebay.com/itm/1PCS-AD623ANZ...
i2c LCD: www.ebay.com/itm/New-Blue-IIC-...
---------------SCHEMATICS-----------
Schematic LM324 non inverting: electronoobs.com/images/Arduin...
Schematic LM324 inverting: electronoobs.com/images/Arduin...
Schematic AD623: electronoobs.com/images/Arduin...
--------------------CODE------------------
electronoobs.com/images/Arduin...
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[@frenchcreekvalley]

Thank you for this video. It is one of the most well done videos that I have seen on this exact subject. And, it's right when I need it. I have been having trouble with DC to DC SSR's failing when using them to power the Chinese 2500 watt ZVS induction heaters. They fail shorted if the get even a momentary overcurrent. So I will attempt to use this kind of circuit to shut the SSR off just before its too late. Wish me luck.

[@P_Manom]

Thank you so much. Looking forward for more amazing project videos in future.

[@frenchcreekvalley]

I can only click on "like" once, but I can thank you again. I watched this video for a second or third time to help me troubleshoot my circuit and now it works just as it should.

[@clarkso65]

Nice video! Keep it up. And thank you so much for sharing your knowledge.

[@00_002]

Great project! I'm building one for a power supply! Might assign the Higher scale to A1 instead of A0 so I can automatically switch it

[@DhouhaBT]

Hello, thank you for this video! i want to ask if i can use this sensor for my project to measuring low current (200mA) ? and how can i use it

[@user-ei8hw5nv9e]

Thank you so much for this video !

[@jetraid]

Maybe you can use a software autoscale when displays "increase current" the arduino can change automatically to the low gain amplifier.

[@johnmellor6065]

excellent tutorial much appreciated

[@remicarmigniani3444]

Looks great! Thanks.

[@bernym4047]

very instructive. Thank you. I guess you could switch the ranges automatically using a relay or mosfet and some more code.

[@electronic7979]

Useful video 👍 Excellent 👍

[@yousaftoki1599]

Great knowledge sir......

[@kudchum236]

Nice work

[@arungeorge6112]

how to measure an ac load current if the ckt is same how to connect the neutral of ac to aurdino negative

[@mickredfox]

verry nice video and explanation, is it possible to read to 10 amp and 20 amp and also on other voltage than 5 volts, 12 volt example?

[@mohimen1617]

how about putting resistance R1 and R2 parallel to the load then in ARD code divide the voltage by R1 to find branch current then using current divider to find main current

[@kHUNROMA]

Hi Thanks and very nice video, Waiting for AC Current Measuring Video too.

[@rumengergushki7260]

Great video. Could you make another one that shows how to measure the voltage in the capacitor voltage with Arduino?

[@DwiNoviantoUntidar]

Can u make an AC Voltage meter using ZMPT101B & Arduino? Cz I have a problem detecting the peak voltage to calculate the Vrms value.

[@bittertruth27]

Hi can you tell how can I add lcd to buck boost converter to measure input voltage and current as well aas output voltage and current

[@Metroid1890]

As far as I know, the current sensor modules for arduino also measure currents of 1A and so on, is it possible to amplify one of those sensors?

[@dimpychhabra20]

Can we use this circuit with altered values to measure current in a hundredth of a milliampere?

[@infiniteman12]

Is the arduino pins is safe to accidental over voltage?. when you put to much voltage in 0-2 A scale?. i think it needs a kind of protection, just like fuse , feedback to disconnect test probes if over voltage happens, zener diode, or else.

[@XNA5000]

Great video man

[@ELECTRONOOBS]

thanks a lot!

[@nielsbaeklund7336]

Why do you use 2 switch when you can simply change the input pins in the software when it reports overflow

[@hansdegroot652]

Do we need the switch? can't we use 2 anlog pins and once the low amps reaches the max just switch to the other one? Or can we destroy the op amp this way?

[@buraka.4199]

Thank you for sharing.I learned a lot of thing from this video.Im working dc motor overload control.this methode very clear.I searched a lot of circuıt aliexpres etc about overload motor control.I analyzed these circuit but ı didnt saw big shunt resıstor.ıt has opamp but no big resistor.ıt has ordınary resistors.How ıt does deal with big current?

[@johnsonisaac4864]

Pls how can I use your code and make adjustment to the lm324 op-amp to be able to measure up to 70A DC current?

[@bosechanra3326]

Can it measure micro amps of current with high precision

[@sachindhondge1551]

Really nice, good thing you did not get the ad624

[@krislenecondinato7836]

Can I ask for the code? Mine is not working. I’m using a 25 mili ohms shunt resistor and I want to measure 0-3A but i think there is something wrong with my code or maybe my gain. Thanksalot🙏

[@laythabdulwahab9498]

Thanks for your video but you mentioned to use non inverting amplifier which right but i saw you used inverting amplifier in diagram please check. Thank you

[@risingredstone5949]

thanks a lot

[@jahandadkhanmandohail8346]

can i measure current using this circuit across a wire i mean when no load?

[@terlumunjoseph6779]

hi great video please can you show how to measure ac current

[@FreeCircuitLab]

Nice video, please zoom in while you are showing program, because in smartphone the small texts are barely readable below 1080p

[@sagarnetworks]

See the configuration of resistor in opamp

[@sgsudhir_]

Can I use 50amp shunt for the same project?

[@TheRESMAT]

Do you have tutorial for max 471?

[@mazharsultan492]

If i use 50A 75mV shunt instead 10A 75mV shunt so what is the voltage drop in input of Arduino? Pls Reply

[@alpogant1071]

can i use 0.22 ohm 5w resistor?

[@maziarbesanj1613]

Sehr gut....Danke

[@chenartahir1865]

how can i build a system and connect 15 samples of MFC (microbial fuel cell) in same time for measuring current (low between 0mA to 3A) and voltage (between 0mV to 800 mV) continuously? I have an oscilloscope, if the system help me to get the reading continuously from the oscilloscope or independently measure them, both way is good for me. Please someone help me.

[@nickpelov]

LM324 is not the greatest opamp and gain of 300 is a bit too much for it. Just take the output of the x50 amp and amplify it x60 with another one. That'll increase the error due offset voltage, but you can null it out in software.

[@caribbeanchild]

you mean amplify by 50 then by 6... that's 300.... not 50 then 60 !!!

[@abimariavargas7086]

Can you make it save on screen the amps when you remove current

[@republicoftutorials6068]

What to change on the code to make it automatic select the range

[@motormadness9975]

wow way to overcomplicated. All you need is an if condition. if in range 0 to 2a - read from pin 1 else read from pin 2 literally 2 lines of code

[@raihanadinugroho4405]

Can i use 50A 75mV shunt instead 10A 75mV shunt ? Btw thank you for the video. It's Very helpful. Sry bad english.

[@akshaykolekar5903]

Hi , I have a problem with this. The Voltage of the battery drops fast. I have use 9v battery it works great but afterwards i saw the voltage, it was 7.2 !!!!

[@anukeshambatkar6255]

Sir how to make multifunction Mppt solar charge controller for 60 Amp or higher with auto detect battery voltage of upto 60 v With over charging and discharging voltage settings

[@samuelcarvalhocosta3274]

I'm trying to build a reader for 30 microampere to 90 microampere. Do you have any suggestion?

[@UzairAli001]

Why you did not use external ADC with 16 bits, it should give enough resolution so we don't need OP AMP right?

[@ikabaitinnisa240]

can u share all material to made it?

[@roperhl]

Can i use 24bit adc instead op amp?

[@hazwanhaikal5240]

Hye bro, great video.. I want to ask how can i measure AC Current using arduino? If u got recomended sensor tell me please.

[@amitpatelpatel144]

What is the refresh rate of your LCD?

[@electrosound4595]

How much we measure current and voltage.

[@kedarprabhudessai]

awesome

[@OrthoRocks]

Hello. Need help with instrumentation amplifier. Could not find AD623 in local market. Can anyone suggest few other options with similar characteristics.

[@OrthoRocks]

No reply till now. It’s a shame being such a active community here still no one care to help out. Not even electonoob

[@lefterisxristianos7970]

Hey could you create a 4-20 current loop with Arduino?

[@omerrahmed]

can this measure ac current ?

[@usmanriaz8396]

2:40 So Ohm's law is I=VR. You are so good

[@ELECTRONOOBS]

Actually ohm law is V= R*I so it would be I = V/R

[@usmanriaz8396]

@@ELECTRONOOBS yes i figured it was a mistake. becaue everything was 1 so results were accurate. Thanks for you reply bro. you inspire me

[@pcmobiletechnicalsolutions8504]

you can set voltage to Aref pin of arduino

[@amnesie6615]

Hello, could you please update your code? Because it is wrong. The scales showing the same and there is no "increase scale" function, also the values of the Resistors are different from the video to your schematic.

[@henrytarveran1243]

Hi there; Just to let you know that... the Code Link isn't responding.!! if it could be fix would be cool to try it. cheers..

[@oooJJooo]

Good job, but at 08:56 you have shown the schematics of an inverting amp... Should be a non-inverting amp, else it will not work as it is :)

[@123yarr]

Can you make a video of how to get 5v and 50ma output of high load like 50V and 120A, down to 5v and 50ma

[@ELECTRONOOBS]

I don't understand you. You have got a load that at 5 volts draws 50mA? so the load is 100 ohms right? So you want the same load at 50V to draw 120A?? That's impossible. If not, explain me again what you want to obtain. Thank you and keep up! Saludos!

[@raymondmichael4987]

Time for another current measurement, this time AC CURRENT up to 200A even more just for the funny of it Greetings from Tanzania 🇹🇿

[@omerrahmed]

any substitute for AD623 ? other than lm324

[@ELECTRONOOBS]

Maybe the ua741cp from TI

[@sunith5428]

Thank you . i want to read voltages all so please help me

[@vovanikotin]

also dont forget to terminate not used 2 opamp of lm324. if not terminated they can consume excess power. Texas instruments channel have very good video about.check it.

[@oceans1291]

Can i use it on arduino uno?

[@lezbriddon]

your circuit diagram shows a 7.5mOhm shunt, should that be a 7.5mVolt shunt? or it it 75.mOhm as its divded by 10a?

[@ELECTRONOOBS]

The shunt resistance is 0.75mOhms and it could withstand maximum 10A. So at 1A there will be a voltage drop of 0.75mV.

[@lezbriddon]

@@ELECTRONOOBS yes most shunts seem to be 75mv, I bought 100a and 200a ones and they are 75mv

[@iitianvlogs9805]

Will it measure Ac??????

[@RehanKhan-ur1yv]

Hi, I wanna make a current control circuit with constant voltage.........what should i do???

[@ELECTRONOOBS]

Well, probablly you could use this same circuit and add a relay. When the arduino detects your preset current value, should open the circuit with the relay. That should be quite safety.

[@RehanKhan-ur1yv]

Thanx

[@caribbeanchild]

I get crazy voltages using the Arduino to measure voltage across a 0.1 Ohm shunt with a 12v bulb as a load.... but no problem measuring that same voltage using a pot to generate the voltage. Pulling my hair out. It seems as though the Arduino ground is not true ground once connected to the simple light bulb circuit! I have no idea how you guys all get this to work!

[@galdankh]

You said that ull use non inverting amp. Then you show schematica with inverting amp.??

[@caffeinatedinsanity2324]

Good video, but just a little note at 2:42 current = V/R, not R x V. Ohm's law says V = R x I

[@usmanriaz8396]

So, let's say we have 1 V voltage drop across the shunt then how to calculate the current then. yes he missed this

[@SverigeKodar]

At around 10 minutes into the video, you talk about calculating the ampere from the value of the ADC. Do you mean that you got 22.871 volt on the analog pin at 10A? Because that can't be right, the Atmel chip would pop like popcorn at that voltage.

[@ELECTRONOOBS]

Pontus Holmberg no way hahaha. the maximum voltage is 5 volts of the ADC. At 10 ampers I say that the voltage drop at the shunt is 75mV, that multiplied by the OPAM gain should give about 3.75 volts. so no way 22 volts, you understood bad. keep up!

[@SverigeKodar]

Yes, I know that the maximum voltage if the Arduino pins are 5v. That's why I had to ask, as you even wrote a comment in your code saying: "Because we have 10A when the voltage is 22.871 for a 304.95 gain" You even say: "with our gain, that voltage drop will have a value of 75 multiplied with 304, which gives us a 22.8 voltage drop for 10 amps of current" and we measure the voltage drop to get the current. So what you're saying is that the op-amp will give out 22.8 volt at when the shunt gives 75mV at 10A, because of 0.075V * 304.95 op-amp gain = 22.871V. I know this can't be true, as you're powering the op-amp with 5V from the Arduino board. But it's sounds very confusing, even I got thrown of when I looked at it first. I know that you mean that for the 0-2A scale, it would (in theory) put out 22.8v at 10A and that the Atmel chip can't handle that :-P By the way, why not use smal relays and npn-transistors to build auto-scaling that kicks in when the output for the 0-2A op-amp goes above 5V? :)

[@ELECTRONOOBS]

Pontus Holmberg yes I say that. but 22 should be for 10 ampers but in that part of the code we are on a 2A scale where the maximum voltage drop should be below 5v. Any higher voltage drop on the shount should saturate the OPAM output at 5v. in the 10a scale as you can see in the code the that the maximum voltage drop.is lower. i hope that i explained well. keep up!

[@Gallardo6669]

Pontus Holmberg great reply,thx!thats what our community needs.... Helping each other!

[@muhammadyasiramin2717]

Sir your session was very helpful but I have a query; can I measure current in kA?

[@genuino-qo5yq]

What is the reason why ad620 does not work?

[@ELECTRONOOBS]

It should also work. AD620 is not an OPAMp, it is an instrumentational amplifier which should be better. Check the confiuguration that you need for this amp in order to amplify in the datasheet. Keep up!

[@SumitKumar-fc4bq]

can you add GPS on your Quad copter

[@ELECTRONOOBS]

Sumit Kumar if you use the multiwii firmware is quite easy to add a gps module. just change a few lines in the config.h code. If you use your own code is quite difficult!

[@jsquaredm]

Looking into this to measure if a robots motor is stalled. Debating if this is worth the effort.

[@BasharatAli-xs7mm]

Hello brother this circuit make with volt and current meter means volt amp Watt and temperature show on one display for 5v Please make a More video

[@AmitSharma-bm2qj]

i think you using wrong formula for voltage gain for Op-Amp you telling for non-inverting op-amp connection but actually you connect op-amp in inverting mode

[@ELECTRONOOBS]

You're right my friend. I've used both inverting and non inverting configurations for this project and I've kind of mixed the formulas in the video. You can now check the description for both inverting and non ionverting schematics with the LM324 OPAM. Thanks a lot!

[@SumitKumar-fc4bq]

I am using my own code you know how to add GPS

[@SumitKumar-fc4bq]

when you make video on quadcopter???

[@ELECTRONOOBS]

Very soon! I have already build 5 of them and the video scripts are quite ready. Till then maybe you should see my Webpage tutorial on drones: www.electronoobs.com/eng_robotica_tut5.php Keep up!

[@Mo-ub6mr]

What is courent

[@anukeshambatkar6255]

Sir how can we measure current of 400 A dc using arduino

[@anukeshambatkar6255]

What changes we have to make in circuit and code

[@deepak_00]

Please add a video on power factor meter.

[@ELECTRONOOBS]

I'm not sure when I will be able to do that. I have a lot of other projects. But just measure voltage at the same time as current and calculate power. Keep uP

[@deepak_00]

Electronoobs thanks for replying, please explain me bit more, measuring current and voltage at same Time will give us it's corresponding amplitude, but how can we relate amplitude with power factor, I know that power factor depends on the impedances of load. That is R/Z

[@ShrinivasSaindar]

I want to measure the current in microamps

[@frenchcreekvalley]

Whoops! Isn't this the way the gain formula SHOULD look?: Av = 1+ R2/R1

[@yofn1541]

why don't you just use analogReference instead of an amplifier ? that will decrease the resolution.

[@ELECTRONOOBS]

the ADC of the arduino has 10 bits that means you have 1024 values for 5 volts. SO that means each value is 5/1024 = 4.8mV. The voltage drop on the shunt will be 7.5mV per each amper so if you want to measure less than an amper you need to make difference between lower values. So you need to amplify the signal so the ADC could measure it!

[@zakkymizanulfikriashsodiq4081]

@@ELECTRONOOBS You can change 5 volt => 1.1V Value = 1.1/1024 Value = 0.00107421875mv

[@Aviprink]

@@ELECTRONOOBS in this case you need better Op-Amp , then use 1% resistor to minimise error.,

[@SumitKumar-fc4bq]

I am trying to make professional Drone camera and I don't think that multiWii can give that much result

[@ELECTRONOOBS]

Multiwii is quite complex. But if you don't like multiwii I recommend you the NAZE boards.

[@cristianbretfelean2805]

kzbin.info/www/bejne/o5SneoeajayNesU Hi. The - and + connections of opamp should be flipped to rectify the schema, cause - should go to ground, right? Thanks for youtubing.

[@abdulkader-lh9mj]

what will be the process for micro amps... ?

[@thewatt3750]

Correction!!! current is equal to voltage over the resistance

[@tucoremirezful]

Nice video !!!! Will you, for money og course, make a project for me ????? 👍👍👍😉😋

[@percivul1786]

Is it just me or does our host sound like he's the brother of AC Ants?

[@kakek8233]

Malaysia

[@metamud8686]

sirkwit .. koerunt

[@cgneptune]

it needs 2 minutes for me to understand his current spelling. it;s not koorent it's current