Part 2 - DIY Lab Bench Power Supply
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- Опубликовано: 12 апр 2025
- If you have more questions, please let me know in the comment section!
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PSU circuit board schematic: i.imgur.com/e5...
Volt/ammeter schematic: i.imgur.com/te...
Components list:
Voltmeter/ammeter display: s.click.aliexp...
Binding posts (similar): s.click.aliexp...
Double rocker switch: s.click.aliexp...
Potentiometer knob: s.click.aliexp...
Rotary switch 6 position: s.click.aliexp...
USB port: s.click.aliexp...
10W 47R resistor: s.click.aliexp...
Rubber pads: s.click.aliexp...
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You've become one of my fav online / youtuber DIY resource and this sort of project has been on my mind for a long while. Now I have no excuse to delay. Many thanks for this high quality presentation. A great job!
I'm not an electronics nerd. I got to this video because I wanted to use my old PC power supply for LED halloween props. This video is well done that even non-electrical types can understand! Thanks for posting
seriously, if every video is detailed like this with explanations, then you've got yourself a fan who will like every video!
A dummy load is mandatory for ANY regulated smps, because they need a certain permanent current draw in order to properly stabilise the output voltage. The reason because some of them can work without a dummy load connected, is because they already have one, which is the actual cooling fan, instead of a simple resistor. But the better, more expensive ones have the fan connected to a separate winding of the chopper transformer, because otherwise, the fan circuitry may induce unwanted noise in the computer power rails, and their dummy load is a resitor, or if the fan is directly connected on the general 12v output, a series voltage regulator ic and a lower voltage fan are used.
I was about to ask exactly this, if I could use the fan instead of a power resistor
fernandoanimator you can, but add another 1500-3300uF low esr capacitor and a 100nF capacitor in paralel with the fan to filter the noise.
I was following the video to build one, my PSUs (actually building 2) have built in Fans. According to the video, he used a 10w 43ohms choke resistor but I could only get the 10w 47ohm, I took it because I thought the difference isn't much. Now when I connected the resistor to the 5v rail (red wire) and Ground, the resistor heats up so much that it began to smoke badly and I quickly have to turn the PSU off.
Tho I noticed, the outputs of my 3.3,5 & 12 was active even without the dummy load resistor. Does that mean my PSU don't need the Dummy load?
A very good explanation about " dummy load "...very useful...thanks for sharing !
For the problem of the selector you talk about at 6:25 : Just put 470R resistor on each cable to the selector (3v/5v/12v...), not the common pin of course. And so, the power supply won't shut down.
And thanks for this excellent tutorial. ONLY USE this tip if you only use the selector for voltage measuring... If you want to use the selector for output to a Vout terminal, use a better selector without the short-circuit problem.
Thanks, very useful, i didnt know how to connect my mini voltmeter, you explained very well, thanx again! 👍
As you, I connected the USB port to main 5v (Red Wire) instead of Purple Standby wire. I did not need to shorted together the data Pins of the USB femele, and during some test my phone is drawing around 900mA, while being at 74%, so success!! As you said, this device is for prototyping not for charging device as phones...
I used one Main Switch to switch the device instead of 2 switchs, because 2 switchs is kind of boring after a while.
I shorted together Green Wire (Power) and some Black Ground Wire, and connected the switch just after the 220v rail. So 1 switch to power the device is neat 😉
Nice followup vid!
I very much like how you explain not only WHAT you are doing but also WHY... instead of just filming yourself making stuff silently like so many others do.
A small note: I noticed that you use the word "consumer" when speaking about the devices you will connect to consume power. This is technically not wrong at all, but could be confusing to some people because the word is almost exclusively used as a generic reference to anyone who buys a product or service.
Alternatives: Load or connected device.
Cheers from Canada!
Hi Sorin, I really like your converted Computer Power Supply, and it was good that you made a follow-up video to answer the various questions and comments. I have read all of the comments, and I really like that someone has noted that there is no protection of the Power Supply (on the DC side). I think that your conversion requires a Fuse Section for all of the DC Outputs, possibly no room inside the Casing, but could be mounted externally. Please could you also consider that many of the people who are watching your videos will most certainly build this useful multi-voltage Power Supply. Many of the people will connect a variety of DC Motors to the modified Power Supply. DC Motors create a large inductive load when the motor is turned off. Without introducing Blocking Diodes into the Circuitry, I have a feeling that the Power Supply (which has been modified by all of your enthusiasts) - may become a disappointment! I really like the work that you do, pl;ease accept this as constructive criticism and I am just an idiot with a Soldering Iron! Do you feel that this needs some further explanation!
For the North America, there needs to be chassis mounted MAIN circuit protection. Either a fuse or circuit breaker mounted next to the power jack.
This will be in my DIY project list. I would preferably add step-up boost board so I can have extra variations in my voltages.
I did it all over again. And it works great. There is a problem when I connect the usb. The Amps are not working so I swapped the grnd from the usb to the other side of the big grnd cable and it works great now thank you 🙏
I appreciate very much this follow-up video. So you're not using the rotary switch to change between outputs, but only to measure voltage and current. (This much I understood right after I watched your tutorial and I was like "huh?")
Your V/A multimeter is different from mine, though they have the very same case. Connections on mine are way different so I had to work them out by myself with some help from the Net. It went well in the end (though I had some shorts here and there, or wired them plain wrong). Generally speaking, ammeters are to be connected in series with the load, while voltmeters must be plugged in parallel. The rotary switch just makes things a little more interesting, though my schematics isn't so different from yours. Figuring out how to actually wire them up in real life is sometimes a pain for people (like me) who try to hack a PC PSU into a bench power supply as their very first electronics project. And it taught me a lot of stuff.
Also, I was "shocked" once by those big caps while testing the PSU to see if it was working, so I learned my lesson: never mess with electrical energy. Thanks for the tips on how to discharge them.
It's just for Voltages, the Ammeter will display any current being used.
Every RUclips tutorial video should be like yours.the first one is good.but this one is excellent, detail and well explained.thumbs up
Just FYI for anybody building a bench PSU from ATX like this. Nowadays you can find breakout boards that do all of the work for you on ebay. I picked up 4 of them for $10 and change delivered (I have no idea how it's profitable. But that's not my problem). They have an ATX (20-pin I think) jack, a power switch, 12V - -12V - 5V - 3.3V outputs, each with a pair of binding posts and a fuse. The only negative really is that with just those wires, you're limited with the output current. But you can just install "high-current" outputs from the rest of the wires on the PSU. At least I think. I'm in the process of trying this theory out along with isolating the secondary in a matched pair that I will then run in series for a theoretical high current 24V output
Your tutorial is very very good, better and best for our knowledge, we are now able & enable to make ATX Bench power supply for our home use.
So that I am v. Thankful to you.
Hi I`m new to electronics if you get a short on the psu when turning the rotary switch from 5v to 12v can you not just solder the 12v to pin 4 so that pin 3 is not used...... 3v pin 1, 5v pin 2 , 12v pin 4 would this arrangement not solve the shorting issue
hi. yes that is true. if you have a rotary switch, that makes contact with the next pin, before it breaks the contact with the last pin (make before break) you can use the pins 1, 3 and 5 for 3.3 ; 5 and 12V.
Dear Sorin,
on 7:24 you recommending low resistor between 22-33 ohm, on the other hand, you mounting low resistor of 3 ohms?
please explain. otherwise, video is superb.
I use a 43ohm resistor in this video. on most power supplies this will work too.
@@Sorin_DIY Oh my mistake, now I see. thanks
I am so dumb to ask if the PSU uses same power consumption as it was being used in a PC or not?
What will be the power consumption, if we only use one 12V supply from PSU?
Will it be same as using it completely?
If I have a psu with 2 12v rails with 19A, and a 5v rail with 20A where shoud I put the load resistor?
Nice project and a very good tutorial. Thanks!
You forgot the part about letting the cat pass, but I guess that doesn't need any further explanation xD ! great video. gave me the confidence to proceed with one of my DIY projects.
I have a atx power supply of 450W. When i connected a 12v/35W car headlight lamp to the 12v supply of my atx power supply the voltage suddenly drops from 12.1V to 10.1V while the lamp only consuming 2.5A current.why this happening?
Note - i have only used single yellow wire and single black wire.
Excellent explanation throughout the project ....Keep it up
extraordinary video, very clear explanation, thank you. I am passionate about electronics although it is not my specialty. I decided to do the same with a power supply I own. You will have been able to do it with a higher voltage and intensity 45 volts for example. Thank you
You have done an excellent job on both parts of your video's. Thank you so much for sharing.
Really great video, perfectly explained and a great follow-up to all questions from your first video! Subscribed
So basically - Can I use DC-DC step down/up converter (0-30V) connected to 5V line, with two potentiometers, connected to display and have basically variable bench power supply?
yes. but I suggest you use the 12V output.
Nice job. I saw the tutorial for this and liked it as well. Cheers and keep up the good work.
@Sorin - DIY Electrical Nerd ammeter reads each volts when knobs is turned, but when i read amps. Each channel is reading same amps. Amp do not change once I turn knob to other devices. Did I hook something up wrong?
Hi. the volt/ammeter is connected correctly. the rotary switch changes only the voltage measurement. the ammeter is connected on the ground wire of the power supply (with its 2 thick wires). the ground wire is common to all the outputs, so the current measurement is also common. the ammeter shows the current used by all the outputs combined.
Ok. Thank you. Is it possible to separate each amp readings without getting complicated?
no. only if you find a high current switch.
salut. poti sa-mi spui din ce magazin online pot sa achizitionez toate componentele? mai ales acel comutator cu 12 pozitii :D
Hi sry für meine fragen aber mein englisch ist leider nicht so gut, ich habe deine beiden Videos gesehen Lab Bench Power Supply Part1 und Part2, und möchte mir selbst eine Lab Bench Power Supply bauen, wäre es möglich genaue angaben zu bekommen welchen Änderungen von Part1 zu Part2 gemacht wurden ?! Also welchen Widerstand für die LED genutzt wurde und welche anderen Änderungen gemacht wurden ?
Danke und Grüße
Hi sry for my questions but my english is not so good, i have seen your two videos Lab Bench Power Supply Part1 and Part2, and i want to build myself a Lab Bench Power Supply, would it be possible to get exact details what changes have been made from Part1 to Part2 ?! So what resistor was used for the LED and what other changes were made ?
Thank you and greetings
hi. for the LED I used a 470ohm resistor. in part 1 I connected the USB port to the +5V standby wire, but it doesn't have enough current, so in part 2 I connected the USB to a +5V red wire.
@@Sorin_DIY ok so exchange the +5v standby against the normal +5v red, well thank you all noted
My knob has 2 pins in the middle which one do I wire the yellow wire from the meter
Sorin,I hadn't noticed but you did include detail for parts and purchase. It was hide below the circuit schematics...Thanks again...
Salut, Sorin! Tocmai am comandat o sursa de tensiune noua pe care vreau sa o transform intr-o sursa similara cu a ta, insa am o intrebare: cum imi pot da seama daca linia de 5V are nevoie de un rezistor sau nu? De asemenea, cum pot diferentiez culorile pentru liniile de 5V si 5VSb fara sa conectez sursa la o placa de baza? Sau merge sa o pornesc si sa masor tensiunea intre GND si fiecare culoare?
salut. daca e sursa pentru PC ar trebui sa aiba aceleasi culori pentru iesirile de 3.3V, 5V si 12V. daca nu au aceleasi culori, trebuie sa le masori. rezistenta se conecteaza la iesirea cu cel mai mare curent.
Hi Sorin, first of all thank you very much for the videos have been a great help, but I have a problem I made the connections according to the scheme when I put the selector in 3.3 v works well just like when I change to 5v but when I change at the 12v position the source goes out, any idea why this happens? Thanks again and I await your response. A big hug
hi. I think there is a problem with the rotary switch. try to move the 12V wire on the next pin of the switch.
Awesome very good and helpful video thanks Pal, I am suscribed to your channel long time ago God bless you from Mexico city
What about canceling the PSU circuit protection?
Salut Sorin, am reusit sa reproduc sursa ta de laborator cu diferenta ca nu i-am montat 5v USB si are in plus sunt de 50 A pt ca voltampermetrul pe care l-am achizitionat era imperecheat si cu acel sunt. Acum, ampermetrul meu imi indica in gol 1.5 A cu ventilatorul pornit si cu rezistenta de 20W/47 ohmi pusa pe canalul de 5V. Pot cumva sa dau ampermetrul la zero din reglajul de pe circuitul lui? Intreb pentru ca nu doresc sa umblu la acel reglaj fara un sfat mai abilitat.
@@Sorin_DIY Salut, multumesc pentru sfaturi. Legasem un pol de la sunt pe rezistenta dummy. Am mutat conexiunea pe negrul de la intrerupatorul sursei si acum totul este in ordine. Multumesc inca o data pentru sfaturi si pentru tutorialul realizat Succes in continuare!
Thank you for sharing this excellent video.
@Sorin - DIY Electrical Nerd thank you for answering, if i put just one resistor like the 10w with 68 or 75 ohms will it still be able to handle the 80amps and will the one resistor get hot?
im useing this project to power a car amplifier for home audio project but the amp is powerful which is why im asking
yes it's ok with one resistor and it will get hot.
Great Explanations , Thanks . Great Video ! Much Better than Most.
Hi question, what dummy load should i use for a 500w power supply (the 5v and the 12v both provide 30amps). Also which one should i connect the dummby load to? (5v or 12v)
Hi. you should connect the dummy load to the output which you use more often. it it is the 12V output, you can connect a 10W 68R resistor.
Thank you very much. I also wanted to ask, The power supply is a X Tech ATX12V V1.3. Does this have short circuit protection? Or would I need to add a fuse to my project to protect it? @Sorin_DIY
Hi, many thanks for this video! Is it true that in the schematic, there is one error: from the Volt/Amp meter you go to the +5V wire, .... shouldn't you take the black to ground and NOT use the 5V? (because how else would the current flow from the selected rotary switch to ground?). I look forward to making this myself.
Maarten Raeymaekers
Strange that ALL those who have build this make the same "mistake". Maybe that would get a genius like you to start thinking about it. lol
hi. the rotary switch is not connected to any consumer, it's connected between the outputs and the voltmeter sensor wire. the +5v wire connected to the volt/ammeter is the power supply wire for the volt/ammeter.
also, the reason the black wire isnt used on the voltmeter header is because its already taken care of on the amp meter header, no need for 2 connections as the volt/amp board has common ground
My PSU doesn't turn on when I connect the green Power On wire to ground. Fan also doesn't spin. Why's that? Please help.
Hi Sorin, I am subscribing you today as I think you deserve it due to your knowledge and creative PSU designs, good work..
Love you videos Sorin, keep up the good work! I've learned a lot from you! Subbed and bell on.
Hi excellent video I just want to ask if it is possible to solve the output I on USB so that it is 1A?
It could be done by putting a potentiometer instead of a 6 position switcher. So that it can be regulated in all values 0-12V. Thank you
hi. you can use a CC/CV step down converter and set it to 5V & 1A or more.
How would you go about making a variable voltage supply off of the 12v connection?
hi. this will also work. but I want to make a separate video with a variable power supply, so I can explain everything about it.
Thanks for great instructions. I have hard time finding 10w 43r resistor. What do you think if i add 2 10w 20r resistors in a row?
that will work.
My power supply fan runs slow, is there a way to speed fan up, by removing what regulates it . Like temp sensor or resistor? The board doesn't read the temps on my added device's and kick fan up higher
Found it..thermistor.. i just relocated it to what gets hot first.. works perfectly.
if you want it to have a fixed high speed, you can connect the fan directly on the 12V output and it will run on max speed. and you can add a few diodes in series with the fan to decrease its speed a bit.
@@Sorin_DIY I had to change some things around.. Had dummy load on 12 v ( was shutting down after a few min) moved it to 5v. Then i had two 12v rails wired together, separated and now it runs brushed rc motors.... the psu has mutliples 12 and 5 volts wire groups.. not sure what for. So I just used one geoup on each 5+ 12+.. doing much better.
I'm presently building this. I couldn''t get the 10w43ohm dummy load resistor. I could only get 10w47ohm, when I soldered it in and power the PSU, it gets very hot and begin to smoke, I have to quickly turn it off. How do I fix this please?
Here a are some things I did differently, the red indicator for the PSU was connected directly to the 3.3v rail since it's a 3v led.
hi. the 47ohm resistor is ok. but did you connected it to the 5V rail or the 12V rail? it should be connected to the 5V rail. you can connect the LED to the 3.3V rail, but you should still put a resistor in series with the LED. otherwise the LED will be very bright and may even get damaged in time. you can try the LED with a 100ohm resistor.
@@Sorin_DIY I connected the dummy to the 5v rail.
Hello, is the Green Switch necessary, or is the Red Main Switch sufficient for the whole system? Thank you
hi. if you solder the green wire to the ground, then you need only one switch for the mains.
My meter is different and shows 5V no matter what the switch position. I had to swap yellow and red wires to read the different outputs and not sure why? Meter is Drok Digital Micro 0-100v 0-100a va. I am also turning one of my 12V rails into a Variable using a step up step down converter. (Dc-Dc LM2577S LM2596S Power N2) When I connect the converter it already has a ground wire attached on one end. Should I connect the other to the binding posts or will that interfere with reading current on the meter?
hi. probably your voltmeter has different wiring colors. you need to find out which one is the sensor wire, and connect that to the center pin of the rotary switch. I did not use that DC converter, but I think the -in and +in are common. you should use the same negative binding post for all the outputs, to read the current for the dc converter too.
@@Sorin_DIY The meter apparently requires an external shunt. Since I don't have room I ordered the same one you used and everything works perfectly. For the variable output I wired the negative as you mentioned (thank you). I wired the positive to the post but for measuring I went from the post to the rotary. This way I can read the adjusted volts and amps after the module which is important for electroplating.
Hi Sorin, thank you very much for this great video a have a question, I need specific amp like 375ma Is it possible to adjust amper, using 360 rotary switch? What kind of setup we should make for this?
hi. this is a fixed voltage/current power supply. you can't limit the current. you need a variable power supply with current limiting possibility. you can add a constant-current / constant-voltage step down converter to the 12V rail, and adjust the voltage and current. I will soon make a variable power supply tutorial, and explain all of this in detail.
Hi, thanks for the wonderful explanation, I have all the components available but I have only a 47 ohm 10W resistor, can I use that?
yes, it should be ok.
Thank you Bro, I completed the power supply today :)
the aesthetic is identical to yours, it has only two clamps
and an extra potentiometer because I added an adjustable 12v output using an LM317 that I had at home.
Hi, so if I got it right the wire which has more current has to be bridged with a resistor depending on the amperage, isn't it? In my case the power supply has the most of the current in the 3.3v wire at 20A so I would bridge it with a resistor. Which one would you suggest me? Very useful info also in this part with which I could understand much more! Thanks
hi. in this case I suggest you connect a 10W 10ohm resistor to the 3.3V rail. the resistor will get a bit hot, so you need to fix it to the metal case.
Thank you very much Sorin!
Hello I did the same thing you did . But when I switch it on I feel some current at the outside of the case.
Maybe you now what to do. Or what I did wrong.
Thank you for the nice looking power supply.
Greetings Rene
hi. you need to check the circuit board and all the connections inside the case. probably a wire or an imperfect joint it's touching the case. or you can use it in a grounded outlet.
Sorin - DIY Electrical Nerd
I Will get it open 😩 and check it again.
It’s so hard to get it closed again
Letting you now when I find something wrong.
Thank you for the reply
There was a solderpin from the board touched the outside of the case when I closed it so that is solved now.
When I did use it for testing something I have the 3.3-5-12volt but it displays no Amps and that’s why I made it. I want to now the Amps. So I did look to the schematic and I did exactly what it said. But no amps.🤔
try to reverse the 2 thick ammeter wires.
Might have been answered already,. But can you run power on all outputs or only what knob has selected?
hi. all the outputs are powered on in the same time. the rotary switch only changes which output is read by the voltmeter.
@@Sorin_DIY thank you, great video btw.
@@Sorin_DIY ammeter reads each volts when knobs is turned, but when i read amps. Each channel is reading same amps. Amp do not change once I turn knob to other devices. Did I hook something up wrong?
hi I add a high step up converter and use as a rotary switch and a
variable resistor two?
The black middle of the three pin connector to power meter is not connected to anything in the schematic is that true?
Yes. It is true.
Your first video was perfect to me understood it well
how to adjust or control the ampere of the power supply in each of the voltages? thank you
hi. this power supply cannot limit the current. I built a separate variable power supply with current limiting feature.
Salut Sorin! Cum pot lua legatura cu tine pentru un proiect ?
salut. poti sa imi trimiti un email - sorin.electrical.nerd@gmail.com
Can this type of computer 🖥 power 🔋 supply be used to make a car battery charger? With the range of volts on like yours, 3v, 5v and 12v, can it be used to restore a flat car battery with about 2 to 3v with selectable current levels too?
If not, can you do a vid showing how to make 1 with those specs that also uses a relay circuit that turns off the charger once the battery is full please.
hi. it's not that simple to charge lead-acid batteries with a PC power supply. you need to limit the current, otherwise you will damage the battery or the power supply. even if the battery is almost dead, you can't connect it directly to 5V. I think the best way is to use the 12V output with 2 powerful step up and step down converters, with current limiting. if the battery has less than 9V, you connect it to the step down converter and slowly charge the battery to 12V with a limited current of a few amps. then you connect it to the step up converter and continue the charging to around 13.5V (depending on the battery) with the current limited to a few amps. a better choice to charge a lead-acid battery is my variable power supply.
Thanks for following up with an FAQ. Subscribed 👍🏼
ANTEC 300 casing for life!
Sorin please help me.. about volt/amp meter.. i followed your video but ampmeter is showing me a total amps that entire PSU has .(DC) I cant find the problem. (Volt meter works great) i connected black wire to ground and red to the negative binding posts.
hi. the ammeter measure the total current for all outputs, because it's connected to the GND and the GND is common to all the outputs. what do you want it to show?
Sorin - DIY Electrical Nerd i have digital volt/amp meter like you. i want it to show amps that some load is drawing.. just like in the video.. example: LEDs are using 5V volts and some mA( i dont want it to show 54A.) the entire current.. i want it show AMPS only when i connect some load to PSU
the ammeter should show the value, only when it's a closed circuit. if you don't connect a load, it should read 0A. check for a short-circuit between the negative output and something else, like the metallic case. if you disconnect the thick ammeter wires and connect only the voltmeter wires, does it show 0A?
@@Sorin_DIY thank you.. i will try that. yes i disconnect ammeter thick wires i reads 0A.
salut; felicitari pentru ceea ce faci; ajuta-ma cu o informatie te rog - unde gasesc acumulatori 18650 la un pret rezonabil?
salut. eu de obicei folosesc acumulatori salvati din baterii de laptop sau alte electronice. daca ai nevoie de acumulatori pentru un dispozitiv de consum mic dar de durata (de ex boxa bluetooth) poti sa folosesti si acumulatori mai ieftini. in Auchan au avut odata la oferta power bank cu o celula de 2000mah la 11 lei. deci poti sa folosesti si celula si modulul de incarcare+ridicator de tensiune la 5v. insa daca ai nevoie de acumulatori pentru un dispozitiv care necesita mai multa putere (becuri, leduri, motorase), ai nevoie de acumulatori de calitate - samsung, panasonic. acestia sunt scumpi, indiferent de unde ii cumperi.
Salut , eu am colectat de la Reparații PC baterii defecte de laptop , le-am desfăcut am testat capacitatea și mai mult de 60% sunt încă foarte bune și mai ales gratis alternativ EBay sau AliExpress preț rezonabil dar calitatea ... Eu locuiesc in Irlanda și pot sa cumpăr 18650 de calitate din mai multe surse dar și aici și acasă am văzut bateri de foarte buna calitate la magazinele pt. Vaping costul e in jur de 10€ bucata. Depinde însă la ce îți trebuie
i just want to ask in the 1st video you manged to attach two or more from the same wire into one like you did with yellow wires is that not going to plus the current in output and as i know, the laboratory staff doesn't need that much of current .
this power supply is useful for testing high current devices, like cordless drills, battery chargers, peltier modules. I will soon make another power supply with variable voltage and current limiting features, which will be used for sensitive circuits.
@@Sorin_DIY thanks man i thought you will never replay to me
now you have my sub
and other question is the current are assemble ? i mean when you attached the 4 yellow wires with each other is that going to assemble the current like 14+14+14+14 = 56 Am !! or all the wires are shearing the same amount which mean the output = 12 Am means that not every single yellow wire have his own 12 Am ? but they shearing it and the value of one yellow wire is the same as 2 or 3 wires attaching to gather ?
i hope you understand what i'm meaning !!!
and thanks again
all the yellow wires share the same output 12V 18A. on the circuit board they are all soldered together. but if you want to use a big amount of current, one wire will not be sufficient, it will get very hot and it cannot deliver the whole amount of current. you need to use more wires. using more yellow wires is exactly like using one thick wire, so it can deliver all the current you need.
@@Sorin_DIY thanks mate
What kind of rotary switch is that I ordered one from eBay and look just like that one but they sent me a piece of junk instead can you help me out on that
hi. I bought the rotary switch from a local store, but you can use this model:
www.aliexpress.com/item/32820242124.html?spm=a2g0o.productlist.0.0.39da4651FgNyNk&algo_pvid=392b7eb8-a901-4ef2-a8f2-4703480355b9&algo_expid=392b7eb8-a901-4ef2-a8f2-4703480355b9-0&btsid=0be3769015936818258578418e1df6&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_
And can u make this atx as a adjustable output,? Because I I'd like to have one,for my work shop,some videos are hard to follow,you have an excellent explanation,so that it is so easily to understand,please,make it.
hi. I will soon make a variable power supply.
@@Sorin_DIY thank you,o don't want to let burn my last atx power supply,I have 5 before,it all burns,by making on it,.
connect positive binding post to one of the terminal of the selector switch to add a voltmeter feature
Excellent project
Hi, today I have recreated this project, but if I connect a load to the powersupply and it shuts off. Can someone know to fix it?
I liked the fact that you incorporate a USB port in that power supply.
When I connect the green and black wire, the fan is switched on, I have the 3-contact switch and the led diode and when I connect green to one output and the black to the second diode is lit but the fan does not turn on and when I connect the black wire to the third output the fan is turn on but the diode is not lights up. Where's the problem?
hi. you use the switch only for turning on the PSU. you connect only the black and green wires to the switch. the LED is connected separately, with a resistor in series, to a 5V rail (red or purple).
@@Sorin_DIY I have a switch with an integrated diode in the switch but it looks like the power supply is defective, smoke is coming out on the primary side. Thanks for the answer.
hi a pc psu that has 450w of power, can it wasting same 450w, with no pc components? please reply fast
hiiii sorin, the video is interesting. so, i made everything except volt/amp meter connection. i don't have rotary switch. i have volt/amp meter like you have. please any suggestions?? I really want to measure both volt and ampere but for 12V only. I will wait for answers. I didn't understand what is the negative binding posts??!!! please specify?????
hi. you can use the voltmeter/ammeter on the 12v rail. it will show you only the voltage for the 12V rail, but it will show the current consumption for all outputs. you can connect the voltmeter red and yellow thin wires to one yellow (12V) wire from the power supply. the negative binding posts are the black connectors for the outputs.
recien vengo de ver el último modelo que sacaste...!!! esta genial....doy like por mas modelos 💡👌
Great videos! If your PSU has multiple 12v rails can you connect them in series for a 24v output? If yes, could you access 12v & 24v outputs simultaneously, or would grounding restrict you to one of the two configurations?
hi. the PSU outputs cannot be connected in series, because they share the same ground.
@@Sorin_DIY Thanks for the reply!
So would there be a way to actually have it to switch voltage based on where the switch position is? to cut down on wires & Binding posts
yes, but this type of rotary switch is rated for low current. if you want to deliver 12V CC with minimum 10A, you need an industrial switch, which is much bigger.
Hi Sorin thanks for posting these informative videos.
I had a look at your variable voltage power supply video but that's a very different build to this. My thought is to use a XL6009 step up module as an output off the 12V rail of my ATX bench power supply build to charge 14.4v (4S) and 18v (5S) rebuilt Li Ion drill battery, what do you think?
addendum: FYI my old ATX PSU had a pink wire! Turns out (after a bit of browsing) to be a sensor wire for the 5v rail, similar to the brown wire for the 3.3v rail. Treat in the same manner.
hi. yes it will work. but for the 4S battery pack I think you need 16.8V. you should read the datasheet of your cells and BMS board. if you don't use the original BMS board of the drill, you need a good BMS for this type of conversion. also the step up converter IC will get very hot, so you need to add a heatsink.
@@Sorin_DIY Thank you that's great advice. And it's no problem to get the V and A showing on the led meter via the 6 way switch, same connection as the other outputs?
I ordered a 20A 4S board (ebay # 202393983053 ), still hasn't arrived yet! Then later I watched DIY Tricks&Tips video FN0mx5n4ocA. The first board he used cuts out when the drill starts. But I think it depends how you set it all up - if you check his circuit diagram 4.30mins, the power for the drill is off the output points on the BM board. If the power for the drill is wired direct, not through the board, then this can't happen right? However then you won't get the protection benefits of the board (discharge limit etc)? I noted that in your (excellent) drill pack rebuild video you just used a pretty low rated board.
Thanks for the video,can i use this power supply to power up phones without battery or for phones fixing or should i reduce the 5v to 4v and how to do so ,thanks.
you need a variable power supply, with current limiting feature. you can check out my other video with a variable power supply.
@@Sorin_DIY okay thanks for the reply
Very well explained. I enjoyed watching the video.
Can You Make a Video on a ATX Power Supply for 24v Battery Charging?
Good Explanation of This one!
Thumbs Up.
Thanks for Uploading
hello sir, any updates on diy variable voltage psu with molex and sata power connections?
Hello, I will make a better power supply with fixed and variable outputs. but I'm still waiting for some components.
@@Sorin_DIY nice. great to hear that. hope it will happen soon. thank you for replying my question and have a great day sir.
When I use the rotary switch the whole thing shuts off when I turn it to select the voltage, I guess it's shorting out but how? Any help would be nice. If I turn the whole thing off and move the switch to a different position and then turn everything on, it works but not when I turn the switch with the power on.... I've wired everything right from your first video (awesome btw) but maybe it's just the rotary switch itself?
He literally said in the video that this issue is caused by an inadequate rotary switch. You can change the rotary switch with a better one that has more room between the leads inside and then see if you still have this issue.
if you can find detailed specs on the switches you might see a term like, "make before break", and "break before make", you need one thats break before make
Please create us a voltage Variable Power Supply. I would love to follow your schematic of it.
Yt is full of DIY videos, but none are worth yours!! Yours videos/schematics are explaned very well! I already followed your instruction to make a DIY 18650 Battery Charger, and it works like a charm. keep the great work, and hope you will be able to give us DIY videos more frequently.
Thanks.
u are legend, mate.. love ur accent.
Can I change dummy load to more useful load such as 10Watt LED?
yes. but be careful on the LED voltage.
sorry but whats the minimum power requirement to turn the power supply on.And where do i connect the dummy load because my power supply's mos current is at 5v and most power at 12v
btw ty for replying really fast last day
hi. you should connect the dummy load on the 5v rail.
thanks again
Thanks for explaining some of the more complicated points. Can the 12v Circuit be tweaked to a 13.8v Output, if so can you explain how this is done.RegardsClive
hi. it's very difficult and it may not work. the simplest way is to add a powerful step up converter.
Ok Thanks Just thinking may be able to adjust one of the pots on the PCB
on some power supplies you can do that, or replace a feedback resistor. but it's difficult to find it and most likely you need to replace other components as well. and in the end the power supply may not work correctly. so it's much safer to use a separate converter.
Nice! Any link where can I buy the wire stripper plier and materials used in this video please?
hi. I've bought the components from a local store. but you can find similar components on aliexpress. here is the link for the wire stripper:
www.aliexpress.com/item/Automatic-Cable-Wire-Stripper-Stripping-Crimper-Crimping-Plier-Cutter-Tool-Diagonal-Cutting-Pliers-Peeled-Pliers/32700817226.html?spm=2114.search0604.3.61.4bec3d1dcdlwof&ws_ab_test=searchweb0_0,searchweb201602_3_10065_10068_319_317_5733915_10696_10924_10084_453_454_10083_10618_5733715_10920_10921_10304_10922_10307_10820_10301_10821_537_536_5733815_10059_10884_5734015_10887_100031_321_322_10103,searchweb201603_51,ppcSwitch_0&algo_expid=8ff52902-2db5-45b4-a36e-4f9fa7c43b52-12&algo_pvid=8ff52902-2db5-45b4-a36e-4f9fa7c43b52
Salut Sorin, I'll write in English in case others have the same question. Can you use this to charge multiple 12v batteries at once? I need to charche some 12-20ah lithium ion ones, and some 12v 7-10ah lead acid ones.
Hi. you can use this power supply, but not directly connected to the batteries or li-ion cells. you need to add a CC/CV converter for each battery/cell. for example for a 12V lead acid battery you need to set the charging voltage to 13.5~14V and limit the current to 10~25% of the battery capacity.
i was planning on buying a lab power supply but this looks much more fun. Will i be able to control how many amps i can put through?
not with this power supply. I made a separate video with a variable power supply with current limiting.
@@Sorin_DIY looks a little complicated for me. want to start with something more simple. if the power supply i will use is rated at 5v 13amp And the device i want to power is 5v 5amp for example will it power it at the max 13amp or it will draw only what is required?
the load will draw only what it needs.
Здраствуйте,а зачем вы белый большой резистор припаяли к 5 вольтам?
Hi, i would like to do it with a variable voltage and ampère separate,
With Two potentiomètre or one with a switch to sélect volts or Amp.
And also can i put 2 other potentiometer inside for calibration .
Nice vidéo be the way 👏👏👏
Thank’s
Hi Sorin, thank you for your explanation and I was able to do a similar lab bench PS even without experience :-). The problem is that with extra wires I´ve added a 12V socket like we have in the cars to connect a vacuum cleaner or to light a cigar but when I connect the vacuum cleaner, the power supply shuts off !! I presume this is because of a peak input current when I connect the vacuum cleaner. What can be done to avoid this ?
Thank you and keep up the good work.
Fernando
hi. you can try to connect a big electrolytic capacitor in parallel with the 12V output, 4700uF 25V. or even 2 capacitors connected in parallel. or you can connect and turn on the vacuum cleaner, before you turn on the power supply.
@@Sorin_DIY Hi Sorin, thank you so much for your feedback. I follow your suggestion and it worked. I can connect now the vacuum cleaner and also a mini compressor without issues. Thank you again. Kind regards.
Can we connect the two 12 volt supply in series to get 24 volts????????
no. they have a common ground.
I want 24 volt from this . wouldn't you help me in this case, please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please
Hello, Sorin, would you mind explaining how you calculate the load resistance?