Homemade Digital Electronic Load | Multiple Modes

[@ELECTRONOOBS]

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[@grodiosp8916]

Why do u put a banana in all your videos???

[@mubbashirshirazi3758]

hey electronoobs it would be a good idea if this project can be used to test the capacity of 18650 batteries by measuring how much current it delivered for a certain time and than display results in the end please please make another version with this improvement

[@lexander9686]

What's up with the Q&A

[@boonematias4131]

i guess im asking randomly but does someone know a method to log back into an instagram account?? I somehow forgot the login password. I love any assistance you can offer me.

[@elliottdaxton7930]

@Boone Matias Instablaster =)

[@ultimateworkshop2000]

Good job, one of the best assemblies I have seen for modules of electronic load, this simplifies it a lot for noobs, but the code is missing some features to complete a prefect job: 1- Set end condition i.e. voltage in order not to destroy and deplete batteries under test. 2- Total capacity in mA or A for batteries testing. 3- Total consumed power. 👍

[@lexander9686]

17:05 i like the fact that it's only V1.0, so there is still a chance of development.

[@gizmoguyar]

This is a sweet project. My only concern is that of response speed. It's probably not a big deal for the vast majority of use cases, but I could see some situations where an input voltage changes rapidly. That could cause a large current surge that could brown out the supply, or cause strange oscillations. For example, in constant power mode, if a supply rapidly switched from low to high current, this load may not be able to increase the resistance fast enough, overloading the supply. Or in constant resistance mode, a reduction to half the voltage will momentarily continue drawing the same current (half the resistance). I think this type of situation is rather unlikely. But it should definitely be kept in mind.

[@dominikworkshop6007]

This problem was a deal-breaker which stopped me from using this design.

[@ninadtaralekar]

It's really nice device and the packaging has made it really professional look

[@keithking1985]

love how alot of the way you get your readings are like how you do it in your DIY multi-meter..

[@ELECTRONOOBS]

Yes, is kind of the same sometimes

[@Zloy_nub]

11:05 , don't put mosfets in linear mode in parallel , drain-to-source resistance changes as mosfet heats up, but they'll not heat up equally even if they're mounted on the same heatsink, you'll get cycle like this until one of the mosfets burns : higher temp => lower resistance => more current = even higher mosfet temperature, so eventually current rated for all mosfets will pass only thru one mosfet you can put them in "parallel" if you read the amperage, and control their gate voltage separately but anyways, cool project :)

[@AngeEinstein]

I'm glad you exist since I definitely can't afford commercial versions of this

[@NiHaoMike64]

When drilling into a heatsink with heatpipes, make sure not to hit the pipes or the refrigerant will escape and the heatpipe won't work. (If you noticed a hiss and a funny smell when you were drilling it, that's what it was.)

[@ELECTRONOOBS]

You're right but in this case, this old cooler was not filled with refrigerant. It's just filled copper tube.

[@widjisantoso3074]

Error = setvalue-actual Pwm = pwm+ error I just use this for the pwm compensation and it's work very well and very stable

[@hemantbabel4279]

Man you are my favourite ❤️❤️ you come up with something unique everytime.

[@leslie1764]

I love how they say get your PCB for $2 and don't say plus the shipping 🤦‍♂️🤦‍♂️🤦‍♂️🤦‍♂️🤦‍♂️

[@raagamparmar179]

yeah....LOL! It sums up to the same price....slightly lower than others.....

[@MarterElectronics]

Shipping can be low as 5 dollars or 20 dollars. It's better than first having to pay 170 dollars for a 4 layer pcb and then 22 dollar shipping.

[@edindelic4841]

Have you checked stability of the system? Especially op Amp driving a mosfet tends to oscillate under some circumstances. Adding some caps in the right position could increase your phase margin of your system.

[@mik310s]

I just finished this curcuit it works great, thank you kindly electronoobs :)

[@volkerraum3494]

Hi, nice Project, I just stumbled about one thing. GND of Sense is directly connected to the common Ground.In case you connect Sense GND and Input GND directly to your power source then the sense GND wire will also have to carry a lot of Amps resulting in Voltage drop over the wire? => Depending on the "thinkness" of the Sense GND wire, the measurement might be impacted less or more. Shouldn't Sense be measured in a differential manner?

[@electronic7979]

Excellent project 👍

[@sajidmohammad3190]

I wanna make the Fan Temperature Controlled...At which 🌡 the fan should turn on and at which 🌡 the fan should run at full speed?

[@Happiness50057]

pls add battery capacity tester feature

[@cwbh10]

Also, I think running MOSFETs in parallel as suggested by running them in the linear region could be non-ideal since the different manufacturing tolerances would make them difficult to control in unison

[@fellpower]

U can fix that very easy by splitting the gate voltage to extra OP Amps - and get that "Gate Voltage" from the MCP splitted to them. Every FET needs his own Shunt - and all is fine

[@checkm8606]

Looks great! Next semester I will start to study electrical engineering:D

[@ELECTRONOOBS]

Welcome to this world. Good luck :)

[@JakeJoris]

Made it, works great. The only issue was that the current was stuck at -500ma, but I resolved the issue by flipping L- and L+ around.

[@jdev999]

On mine the current showed a negative value, also had to swop L+ and L-

[@Catstorm99]

Perfect timing...I was looking for one until I saw how much they were. Might build my own now. Thanks for your content.

[@alexe7376]

I did the similar project 2 years ago. I used INA219 as a current sensor together with 0.1Ohm sense resistor. It more accurate than ACS712, has I2C interface and 0.1 resistor produces less heat.

[@ttthierry2544]

Good morning. Did you put your project on the internet?

[@abzaman77]

A Watt-hour counter and an automatic voltage cutoff feature would make this perfect I believe.

[@lezbriddon]

1ohm is maybe a little high (voltage drop to connected equipment) simple suggestion for a bigger/better monster v2..... mosfet x3 to share the heat 0.1ohm (10x1ohm parallel less heat/less value drift so more accuracy) tl072/358/741 opamp to multiply small currents before adc (switchable? 1x 10x etc) less ugly display option, small but pretty oled ones are like $8 sdcard logging......

[@atec9228]

Sería estupendo un diseño en PCB en vez de tanto cable y placa de prototipos. Magnifico video.

[@homoevolutus]

Can't wait to build one! Sometimes it's best to order the parts right away before watching the whole video and deciding a project is too complicated. Not this time!! Also, XD @5:56

[@lexander9686]

Thanks for the advice.

[@PrUveTGoogl]

Спасибо большое что делитесь своими опытами 👍

[@ahmadmaaz2566]

As always, the bestest video ever.... Can't describe in words how much i was waiting for this video...awesome work dude

[@mhzxtal6665]

I am your pateroner, very happy to see this kind of project. It is very useful and you have fully utilized the microcontroller using a good example and best coding way to produce the user friendly features. I love it !!!!! I am your fan haha. Previously, I asked you question and you was responsive to answer my question on pateron chat. I was doing the smart watch project the latest version. But I realized that using the ATmega328-MU the footprint is difficult to solder, I try many best way to solder this and apply the flux to ensure solder paste can properly isolate and solder tightly. I keep trying more than 6 times to program the MCU but stii failed. I read many videos how you burn the code in a blank chip. But I am going to re draw the PCB and change it to ATmega328-AU, i guess using the larger size of ATMEGA328-AU then I can only successfully. Anyway, I really like your project so far. Hope you keep on post more, stay healthy and safe during this period. God bless you.

[@ELECTRONOOBS]

Thank you very much. For the small chip, do you have a hot air gun? Using a lot of flux it shouldn't be that difficult. And yes, the au version is a bit easier to solder because you can see the pins. Keep up!

[@mhzxtal6665]

@@ELECTRONOOBS yes, i used heat gun. I properly to solder and apply the flux to ensure the isolation for each pins. I am not sure why still failed to download the code. I also follow the several video to burn the bootloader. Nevermind, i will keep trying out and let you know once i success to make it.

[@atec9228]

Hola, el esquemático cuando lo descargo luego no se ve bien. Podrías subirlo en Google Drive o algo así para poder imprimirlo y así montar mi unidad de carga electronica. Gracias

[@prussian7]

I was going to make an old fashioned resistor box. But after watching this I am re-thinking that.

[@fabiomatys]

Very nice project... In the next version you can implement one PID controller...

[@ahsanshahid2206]

you could also attach the 1 ohm shunt resistor to the heatsink, I guess it would be pretty hot if high voltages were to be used

[@SudiptaMandalsuri]

Is it safe to drive mosfet directly from DAC without any mosfet driver?

[@ahmedsoliman4209]

I would suggest to start using the STM32 breakout boards for your projects, since the Arduino nano and uno limits clearly start to show up for advanced ones like this one, and it makes you take more time and waste more money on fixing them while you can foucs that on the project making it better, I but really did enjoy watching that build, it was quite the improvement form the last one and more unique not just a circuit that you found on the internet and copied.

[@cwbh10]

Why didn't you use PWM on the gate of the mosfet so that you could dump the energy into a passive resistor and keep the MOSFET out of the linear region?

[@EdwinFairchild]

if you PWM the mosfet would the load also see a PWM signal, and what is wanted is a constant signal, efficiency is NOT wanted in this case if the point is to stress the load...as far as i can tell

[@stevencraig]

Hi, can you elaborate on what you mean here? Specifically where the passive resistor goes

[@lucianungurean]

Great project I already made your project . Also some minor modifications . I saw that it couldn't get to higher currents due to the 1 Ohm resistor . basically your dropping way too much power on the resistor . I put a 0.5 ohms and arrived at 4 Amps with Just 1 Mosfet . the Idea is to ad a standard Shunt so all the power can be dissipated on the mosfets . I already made a 400Watt DC Load using the same ADC and DAC with adruino with1% accuracy . but my problem is that i could never understand how to make a Menu . I'm hopping that I could use your Code and modify it so id have a more extended functions . Beautiful Project

[@Circuitoptimize23]

One of the best Arduino project. Thank u for sharing...

[@giulianoLP2505]

Question: Why not a INA family current-shunt monitor?

[@-bru-NO]

No pinchaste esa heatpipe cuando perforaste el cooler? XD

[@RexMods]

Is it possible to have higher gain, say with R7=2kohm, R6=2kohm? What is the maximum voltage for the MOSFET, the Vgs in the datasheet? So 20V? Thanks!

[@Atif_gammer]

Very nice project. Thank you sir.

[@randycarter2001]

A word of warning. If you use this device to test batteries, add a cutoff relay. Batteries are never off. If the MOSFET shorts out (most likely failure mode) bad things happen like fire.

[@ELECTRONOOBS]

Thank you for this great tip!

[@bitsurfer0101]

Maybe add a current clamping circuit?

[@randycarter2001]

@@bitsurfer0101 No circuit is going to protect this device. What would happen if you're load testing a battery and the MOSFET shorts out? The full current of the battery will start surging through and begin heating wires and other parts to the point of ignition aka FIRE. Either you need a fuse or a relay in series with the battery to shut things down in the event of catastrophe. Don't ask me how I know! A relay has the additional benefit of completely opening the circuit at the end of your battery capacity test.

[@bitsurfer0101]

Randy Carter What are your engineering qualifications? Have you designed a similar circuit?

[@machmanish1]

this is a great project. I want to know, how you made variable resistor for resistor mode?

[@atec9228]

Me gusto mucho este proyecto, vas a compartir los ficheros para poder hacer la pcb y modificarlos?? Gracias por este y otros proyectos tan interesantes. Un saludo.

[@protonspeed]

Can i use AUTOPID library to create constant close loop system ??

[@RMquickbit]

Can you simply parallel the mosfets without any other modifications?

[@mar24n35]

Hi. Great tutoral and i had replicate one using the schematc all work greatl, but if i setup my power source to Give i.g 5 amp a setup the load for 2 amp or something , is drain8ng always max 1.2 amp. From 0 to 1.2 amp setup on the load all works great but any think over is always showing 1.2 amp drain. Is that mofset averhited or something alse? Thx

[@PortraitArtPhoto123]

What would be the best way to build this for higher loads? I have 30ah 12s 50v lipo batteries I need to discharge after to work to storage voltage. So that like's 1500 watts at 1C. Some have said driving multiple MOSFETs could be problematic. Would it be more efficient if that actually fed a bank of high-power resistors?

[@harikamalakarreddydarapu7410]

You are awesome and always your projects are brilliant

[@ELECTRONOOBS]

Thank you very much!

[@JurekPrzezdziecki]

There is an error on your schematic. The RST pin is connected to ground and the microcontroller is on reset all the time. So the program won't run. Am I right?

[@widjisantoso3074]

Did you read my mind? I just looking for this stuff 👍🏿

[@mutthunaveen]

I ve built it... The current shows always negative... I ve posted in your website too... Is that simple change of shunt connection or more? Please help.. Also in ads1115 driver you need to change 8 to 9 for waittime... Please mention that too.. Otherwise it is good work brother...

[@ELECTRONOOBS]

If it shows negative I think you connected L+ and L- to the ADC in reverse. electronoobs.com/eng_arduino_tut123_sch1.php

[@umer6069]

Which gauge of wire did you use to connect to the mosfet.

[@aurthorthing7403]

Oh heck, I missed the other one you built. I think I can handle building that first one. Thank you.

[@franzhagemuller6413]

Maybe you should consider calibrating your oscilloscope probe... Otherwise great video!

[@lexander9686]

Great, im gonna collect the components tomorrow. Thanks

[@pinoyenginerd1091]

Nice , i will also use this idea for my project.

[@makkam7575]

Amazing video as always and nice job on the exterior but at 8:49 it's not 0 to 4096 as in the case of the arduino it's 0 to 255 not 256.

[@EasyOne]

Nicely done

[@DIYwithBatteries]

That was a nice circuit Dude! 😍 Might be useful for a capacity test for 18650's.

[@ELECTRONOOBS]

Thank you. They should be interesting to test

[@DIYwithBatteries]

@@ELECTRONOOBS Yup! 🤟

[@lexander9686]

@@DIYwithBatteries you have a cool channel too.

[@RK-dp9fe]

I was thinking the same think. If yoy can make it count the mAh, time and ad a cut of voltage it will be great for 18650.

[@AndreasA.S.]

you should really look into ferrules for things like the mosfets, solder on a hotpoint, ripe for failure

[@oktemee]

Good job! I have a question though. With the analog version there was an op-amp at the input of the FET in a feedback configuration. This time the DAC drives the FET directly without any feedback configuration. How do you know the FET drive voltage for a specific amount of current. Is there a digital feedback control?

[@RicardoPenders]

You can increase the accuracy of the Arduino from 8 bit to 10 bit for the PWM output and to measure more accurate you can increase the analog input from 10 bit to 12 bit

[@protonspeed]

To increase the accuracy can we use 16bit pwm output??

[@RicardoPenders]

@@protonspeed nope, on arduino 12 bit is the absolute highest you can go, of course you can use another chip that does the conversion in 16 bit and then communicates it back to the arduino via serial communication.

[@protonspeed]

@@RicardoPenders Arduino uno does have 16bit Timer, it's called Timer 1,so it's possible to generate 16bit PWM by Arduino it self. Isn't it ?🙂

[@RicardoPenders]

@@protonspeed not sure about that, I thought it was 12 bit tops

[@protonspeed]

@@RicardoPenders Nah, I've been using 16bit pwm for my project.😊

[@mubbashirshirazi3758]

hey electronoobs it would be a good idea if this project can be used to test the capacity of 18650 batteries by measuring how much current it delivered for a certain time and than display results in the end please please make another version with this improvement

[@adeshkumar5534]

is there any voltage limiting factor here? actually i wanted to test my lithium ion cell using this...will it work for such low voltage of 3V?

[@mubbashirshirazi3758]

very very great project i made the previous version of this projet and and iam willing to upgrade it

[@jrausa1]

Hi- Thanks for posting this. I’d like to build it, but I have one question. The link you provided for the fan looks nothing like what you actually used. Do I need to get a heat sink and fan separately, or are they available as one unit? Can you provide additional links if necessary? Thanks again.

[@LitesLAB]

Excellent project! Very useful in a lot of cases!

[@keithfetterly4111]

As always, outstanding! Keep up your amazing work.

[@ELECTRONOOBS]

Thank you!

[@jdelectron]

can we integrate with lion battery capacity tester

[@Guru_369]

Awesome video as usual 💪🏽

[@ELECTRONOOBS]

Thank you very much!

[@dominikworkshop6007]

This electronic load is cool, I like it! I wanted to build a very similar load and because I had some problems I didn't do it, but now that I've seen this video I plan do start building it, finaly :) But I would add more power MOSFETs to share the load, because MOSFETs with great SOA (safe operating area) are expensive, and if you choose a MOSFET that isn't designed to work in it's saturation region (where it dissipates a lot of power) it might damage over time.

[@ELECTRONOOBS]

Nice. Let us know how your project is going! Keep up!

[@dominikworkshop6007]

Update: I finally built my load and recorded a video about it on my channel. I know it took a while, but I made sure to resolve all common problems found in most DIY designs.

[@BeetleJuice1980]

Great, can you add mAh to the code to measure capacity?

[@ATLaboratory]

Very very nice the all project! Also the case and the menu:) but I'm not sure the MOSFET is properly driven by the DAC. You should use an OP-AMP stage. I know it is not that easier to get also resistance and costant power!

[@barry2718]

Great build. Liked all the explanations and problem solving along the way. I would suggest you raise the 1 ohm 5 watt resistor above the protoboard to prevent burning of that board at full current. An excellent build

[@1996misterio]

Ostias colega ... lo haces mas grande y no te cabe en casa, podría ocupar una cuarta parte de lo que te ha ocupado a ti jajaja

[@elektrocat8681]

Can you make a tutorial about how to make an audio power meter? It should be a pretty similar project but with AC instead of DC. You make awesome videos :D

[@circuitdesolator]

Next version could be voice controlled. Add some mic with tinyML on MCU and say the command "Set CC at 1A" 😁 Awesome work. Keep it up 👍🏼😊

[@Mangomesh]

I love it. Your videos are very inspiring. thanks again!

[@farhadsaberi]

It is not possible using a 1 ohm 5W resistor for a 5 A load. Resistor will dissipate 25W of power and smoke and burn up. Maximum load would be ~2A with that 5W resistor. Must use a 50W resistor for a 5 Amp load. Can you explain your shunt resistor choice please? thanks.

[@victoriaemily6554]

You are the best for me.

[@sasazenny1750]

thats a great project hope you build a li ion balance charger and discharger its already quite similar to this project

[@desmondhow343]

It's so cool I try to make one for myself. Good video.

[@ELECTRONOOBS]

Thank you. I hope you will make It!

[@Guru_369]

Bro need more video related to power electronics...

[@muhammadshahzaib3813]

add battery capacity measuring feature it can be hard since cc-mode is already there.

[@joseraulbuarquecosta3994]

Great job, amazing results, unfortunately I need one capable to handle 30V @10A (300W), Do you know If ia possible to get this Power?

[@ELECTRONOOBS]

Yes, amplify the DAC output and maybe put more mosfets in parallel. Use a good heat dissipator!

[@joseraulbuarquecosta3994]

@@ELECTRONOOBS thanks, I'll try It. It's really one amazing project. You're my hero.

[@backyardscience9060]

Which animations software does you using

[@TheJay6621]

Banana got his terminals. hahahah Nice work.

[@boardinrider]

Why a 5 watt 1 Ohm resistor? can it be smaller?

[@vizkoze]

Did you isolate the mosfet from the heatsink? Usually one of the pins is connected to the back part too. So if you screw it to the heatsink, chances are your heatsink will have the same potential as the source.

[@ELECTRONOOBS]

Is not insulated so yes, the heatsink will have the same potential. In this case is the drain. There are still some parts to improve, yes...

[@vizkoze]

@@ELECTRONOOBS good you left the heatsink floating and used a wooden case 😉

[@neerajchhajed]

Amazing explanation

[@capt.arielmangcoy4484]

Hi, can I buy the complete kit from you for 60 VDV/12amps

[@neerajhebbar7313]

Your Videos are love 🥰

[@jaroserafin9606]

Very nice work. Any possibility to run this device in higher load?

[@ethzero]

When you need to air-cool your MOSFET to Absolute Zero, giant heat sink + fan 😂👍🏻

[@TnInventor]

i find it hard to follow the code , so many parts are not commented , but never the less its an amazing project

[@atec9228]

También sería interesante que subieras el propio fichero easyeda para poder hacer el pcb. Un saludo.

[@ranganatennakoon]

nice project i love it