Build your own Variable Lab Bench Power Supply
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- čas přidán 21. 08. 2024
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In this video I will show you how I combined a LTC3780, which is a powerful 130W Step Up/Step Down converter, with a 12V 5A power supply to create an adjustable lab bench power supply (0.8V-29.4V || 0.3A-6A). The performance is quite good in comparison with other models which cost around the same.
Music:
2011 Lookalike by Bartlebeats
Parts list (affiliate links):
Ebay: LTC3780: rover.ebay.com/...
Aliexpress:
1x LTC 3780: s.click.aliexp...
1x 12V 5A Power Supply: s.click.aliexp...
1x AC Input: s.click.aliexp...
1x AC Switch: s.click.aliexp...
1x Voltage/Current Display: s.click.aliexp...
2x Binding post: s.click.aliexp...
1x 200kΩ Potentiometer: s.click.aliexp...
1x 500kΩ Potentiometer: s.click.aliexp...
Amazon.de:
1x LTC 3780: -
1x 12V 5A Power Supply: amzn.to/1FIc4vK
1x AC Input: amzn.to/1FIc7b5
1x AC Switch: amzn.to/1FIceDs
1x Voltage/Current Display: amzn.to/1AwUnt8
2x Binding post: amzn.to/1ENKLzo
1x 200kΩ Potentiometer: amzn.to/1ENKQmP
1x 500kΩ Potentiometer: amzn.to/1AwUEfD
2x Knobs: amzn.to/1FIcuCC
Amazon.co.uk:
1x LTC 3780: -
1x 12V 5A Power Supply: amzn.to/1FId7fh
1x AC Input: amzn.to/1R1lRl9
1x AC Switch: amzn.to/1AwWsoT
1x Voltage/Current Display: amzn.to/1AwWFsa
2x Binding post: amzn.to/1ENM3uh
1x 200kΩ Potentiometer: amzn.to/1FIdAyb
1x 500kΩ Potentiometer: amzn.to/1FIdBSx
2x Knobs: amzn.to/1AwXvoY
Minor enhancement, there are 2 on board LEDs. One for power and the other for "fault".
I took these 2 LED off the board and added wires to LEDs that I added to the front of the box.
mick florey Sounds good.
great point! TY
hello, what type of leds do you have on the front? and what voltage for these leds? thank you
@@jeanmaurin5273 I used small standard red/ green led. I assumed that the circuitry included some sort of current limiting. Voltage is usually 1 to 1.5v. Still working!
I made this supply about four years ago, and have used it most every day since. Learned a whole lot about electronics in the process, and plan to learn a whole lot more. Thanks for the awesome build guide!
Edit: Just remembered, I don't know if they sell that buck boost converter board anymore, but if anyone is playing with it, it's a three layer board. I shorted an internal trace out when I was trying to desolder the pots my first time around, and had to wait a week for a new one lol. Be careful with the iron when desoldering, and let the pot fall out like he shows if you can, if you try to pull it out too hard you can mess up a sandwiched layer.
Its a terrible design. MOSs' blow up pretty easy. I found that a simple 8A XL4016 module does a better job than this as a variable supply.
A quick note - just tried this with two LTC 3780, and both gave faults out of the box. While trying to respect the "do not touch" the under-voltage protection pot in the end that needed turning clockwise a lot to get the fault light to go out and the OK LED to go on. Worth considering in case you see this too -- thanks for an excellent video!
I am currently building this and I have found that when you remove the 500K pot and connect some wires to a new 500k pot on the front panel, it can pick up lots of noise from any nearby source (including your hands, nearby switch-mode PSUs, lights, etc.). For instance, with no load and long wires to the 500K pot, the DC-DC converter draws about 100mA and even then the current varies quite a lot (it should be 20mA with no load!), but if I put my hand near the long wires going to the 500K pot, the DC-DC converter draws 1 Amp or more with no load! It is picking up noise due to the high impedance of the circuit. This can also cause the DC-DC converter to misbehave and the fault LED may come on or the output may go wild or just cut off. This is especially bad at the higher output voltages where the resistance approaches 500K. You can tell it is drawing a large current because the heatsinks on the DC-DC board get hot and they should not get hot with no load! So I cut the ends off a shielded USB cable and used it to connect to the 500K pot on the front panel, I also connected the braided shield of the cable at the DC-DC board end to 0V input on the DC-DC board (the other end of the braiding is not connected at the pot end). Now it draws 20mA with no load even if I put my hand on the pot or around the shielded cable. The 200K pot should also be wired up using shielded cable too.
Thank you very much for sharing this. 🙂
Thank you for noticing !
you might want to shield those wires to the ground reference
Thanks, very helpful. Can we lengthen the wires by adding longer wires or will that effect the accuracty of the meter?
@@johns2590 You need to use a shielded multi-wire cable for the pots as explained above! Keep as short as possible. make sure you ground the shield braid at one end.
Fantastic video and I love how you showed people to earth the chassis
We're missing your videos Sir!
Afrotechmods Thank you For Both :)
do I still have to do that if my enclosure is plastic
Why r u not in?
Thanks, very helpful. Can we lengthen the wires by adding longer wires or will that effect the accuracty of the meter?
Great tutorial Scott but I think you're missing a very important safety feature. A fuse on the AC input! Considering you are using a "no-name" power supply I think this is essential. Also, leaving those AC contacts unprotected like that makes me cringe, some crimp connecters would be great but some heatshrink would be good enough I guess.
Hampus Sandberg Yep, installing fuse protection & using heatshink on all exposed terminal connections where safety feature I installed into my version of this project.
***** I have been bench testing a Sure Electronics 2 x 100 watt amp module with my DIY version of this benchtop power supply at 24v 2A running a 500hz test tone over night. I did a thermal test using a thermal imager & the temps where barely above ambient even though my enclosure is a sealed enclosure so I don't think a fan is required for this design.
Those LED psus have fuses in them. I know this is a really old comment but thought I'd reply for others who read.
But you heard him. He's lazy.
The 12v 5a power supply already have a internal fuse inside so there is no problem
i like the way you deal with your mistakes for theses videos. we all mess up, and its refreshing to know that there are people not afraid to admit it.
This is an awesome project video. I love your style!! Articulate - detailed - fast paced - - logical flowing - and doesn't dwell on insignificant details. It always seems that as soon as I have a question - yup - you just answered it in your next comment. Best electronics videos on the Web. Keep up the great work !!
+Donald Filbert Thanks for the feedback.
GreatScott!
will I get higher output current from ltc if I'll use 12 v 10 amp power supply as input.?
Did you hear of a channel called "The Post Apocalyptic Inventor"? He is German too and has a lot of creative electronic projects too.
I really like his channel ("The Post Apocalyptic Inventor") ... but now he's moving his lab and it's been a hard time since he's running out of time to post projects videos. Looking forward to seeing what will be coming from now on.
Btw, He lives in Cologne, Germany. Also from Cologne is Laura Kampf (channel about 'making things').
Robledo Einstein Mein Kampf!
I think it'd be really cool if you did a series on designing, prototyping, and then building your own power supply from the ground up.
a 2019 quick update with new tech (new recommendations) would be awesome!
I would love to see this as well!!
I'm just going to an AC DC adapter for my power supply:
www.ebay.com.au/i/263922220439?chn=ps&norover=1&mkevt=1&mkrid=705-139619-5960-0&mkcid=2&itemid=263922220439&targetid=469489693418&device=c&mktype=pla&googleloc=9069204&campaignid=1793098931&mkgroupid=74958853168&rlsatarget=aud-497372010363:pla-469489693418&abcId=1139226&merchantid=116254190&gclid=Cj0KCQjwl8XtBRDAARIsAKfwtxBqWxCzqCuXbzmGCkSIUDzucEOlcvWIdYDtktyb_-HB6rDzgXsTga4aAoKmEALw_wcB&var=563368613478
This seems like a simple cheap solution. Can anyone tell me why this is a bad idea?
.
@@m2j8 it's safer, use it.
Michael Jenkins it’s not a bad idea :) I’m using external ones too. I’ve got 3 channels on mine and can run it off of a power supply, MacBook charger or a lithium battery.
Everyone says " just buy one." You're missing the point; you learn things from DIY. This doesn't have to be your ONLY power supply. This is a great instructable.
Rather then rap stranded wire around a screw and washer, it would make more safety sense to use a spade-lug.
No danger of that slipping!
washer or forked crimped or soldered lug = professional job, twisted wire = rank amateur. There are plenty of "professional" electricians I know who are rank amateurs when it comes to wire and cable terminations!
And a drop of solder wouldn't go astray..
It's probably fine though..
You should NEVER solder an earth/ground connection. In the event of a high current fault the solder can melt (just like the resistor solder in the video!). Spade crimp connectors only the the IEC inlet. Wrapping the wire isn't the best method, but it's way better than the soldered version!!
@@davidmoore2892 - Agree!
Hey folks I'm a ChemE who occasionally wires up Pilot equipment...
I've never really thought about how grounding should be done and definitely have wrapped/soldered before. I will never do that again.
Please know that your youtube comments made me a better engineer, and may have even saved a life. Cheers.
for the AC side, you should have used cable shoes. Especially for the protective earth connection
Any time I read things on Instructables, I imagine your voice reading it.. I can't help it :-\
Dee Jay It's a curse ;-)
I used to watch these videos in college thinking when I earn I will make all this for myself. Now, I am back here earning and thinking to start this again. A great great thanks to GREAT SCOTT for all this content
Well done! But I have still a few notes! For the best soldering, first heat up the parts you want to solder and then add the tin, it looks like you don't do that with the wires carrying the main voltage. You should also heat shrink them. You should also use a lug for the earth connection, you could use a lug wich you can attach to the cable (crimping) or a lug which you can bolt to the chassis (solder the cable and use heat shrink tubing).
I love the system engineering and specification of this power supply. Simple yet very powerful.
What I consider to be improved: You don´t have access to a proper crimp tool, so you had to solder the mains wiring. I recommend investing in a crimp tool and the corresponding contacts. It looks better and is safer in the long run. I know that crimp tools are expansive - but crimping is one of the highest quality contacts and - once you have the tool - it is relatively inexpensive.
+sarowie I would argue that a soldered contact is as good or better, if he just heat shrinked it afterwards for safety.
SteelBlueVision
heat shrink is sure enough a valid alternative.
I personally still prefer crimping, but it comes down to personal preferences and experiences. Crimping can be done by anyone "following the book", while soldering is a bit of an art. Having bad solder wire, a bad day or a burned out solder tip can ruin the job in the long run, while a crimp is either good or bad at it´s easier to tell the difference.
Ya, I would agree with you here. Some nice crimped male female connectors, or just donut round connectors would be more professional than soldering everything together permanently. Although, if it is just for me and me only, I don't think I would mind...right up until it breaks, and I have to desolder everything just to take the board out lol.
48 people got electrocuted and missed the like button
+Reason 2 Die Gamer hahahahah
+Efthimis kritikos 72+!
Efthimis kritikos this was two months ago :P
+Reason 2 Die Gamer it's 91+ now
Robert Slackware OH WOW! imma try this but which ones. the high or low voltage?
I've built one similar to this before. What I would add is either a couple of smaller pots in series for micro adjustments or put precision multi turn pots in place of these for a finer control. You could also go a bigger input power supply as the regulator can handle up to 130W. Also, add a shake proof washer to that earth lead on the chassis - you never want that coming off for safety.
These days it's so easy and quicker to make power supplies than it's ever been.
It can handle 130W but only for a limited time, without added heat dissipation. The long-term output power is stated at 80W.
I built a variant of this power supply 6 years ago as well as a smaller one of a different design about a year later. Six years on & both bench power supplies are still going strong with my using this variant just this evening to help build another electronics project.
A couple things - 1) you should include a fuse in the ac primary circuit and, 2) place the binding posts 0.75” apart so you can use a dual binding post connector.
LETS GETS STARTEDS!
From the scrap department of my work i was once able to retrieve a whole stack of 45 volt / 70 amps (3.2kW) lab power supplies. Both voltage and amps stepless adjustable. They can work on both single phase as wel 3-phase input :-) You can start a car on them with ease. Though they are a bit bulky for little electronics projects. Delta Elektronika SM 45-70 :-)
cool, do you sell these?
Best Power Supply I ever made. I also added a Constant Voltage, Constant Current Output (12V 3A). Thank you Great Scott for the idea!
U should use a 12v 15a ac-dc converter. Because you can't reach the maximum power 180w with the 5a one.
True.. Have you make this project yet? I'm thinking of using a 12V 10A DC. What do you think? Thank you
Can we use laptop power adapter for ac to DC conversion I’ve 20v 7a one
it was hard to watch you screwing in the first two wires c'mon just grab the blue connector not the board.
Thankyou for the 'cup of water' tip - I'm building a power supply, and today's testing will include redistor current dump.
Your advice probably saved my workbench. ❤
Thanks, made a slightly different one that puts out 3A. Been wanting to make one for a while. Now I've got one for a fraction of the cost and is easily upgradable.
there is a method where you can use a computer PSu and control its various outputs with variable resistors, eg 12v can be 10 or 17v
+GreatScott! Where did you get the outside case for this build. I haven't been able to find one.
Very nice tutorial, i saw it a while ago, and i decided to make it myself. Bought all the components, put everything toguether and... surprise!!! once I take the voltage past 13 volts, the volt-amp meter just shuts down, while i hear an annoying buzzing... I spent a few hours trying to redo the setup, trying to find any stupid mistake I may made, and then I thought about the fact that the volt/amp display shows that the power supply and the mesurements should be isolated.... so i put a general purpouse diode between the 12V/5A power supply and the positive connection to the volt/ampmeter and everything seems to be working now. The buzzing sound is still there, i still need to test the power supply with some load on it, but it works. I just put this here just in case someone happends to be in the same situation as me. Great video tutorial Scott!!!
thank you Scot about a idea! Today I finished a project after a 2 months of waiting a parts from ebay :D . I changed some parts. I ordered a 10A 12V LED driver as a LTC3780 can provide at least a 7-8A of current. Also to provide higher precision of adjusments I added in series 20k pot before 200k pot and added 50k pot before 500k pot, so now I have coarse and fine adjustments. Also I added a 12V ventilator for cooling and switch for turning on DC (more to turn of i emergency case)
+Connor Bisby Give me your e-mail, I can send you some schematics. I have no idea how to attach it to arduino - i'm quite retarded in programming
+Jam Jamamam I want to do this project. It works 100%?
+Alexander Ruiz Yes, i made it couple weeks ago and tested with some DC projects (electrolysis, electrolysis etching, charging batteries etc.). Only downside is chineese volt/amp meter - it lies up to 0,7V, so you have to double check voltage with multimeter (if precise value is necessary). Otherwise it's great.
+Jam Jamamam
I have a switching power supply of 32V and 2.5A. Using the LTC 3780, could more or less regulation 0.7-30v a 2.5A current limit?
+Alexander Ruiz yes, it should be possible
it would be very useful if one could show a way on how to control the output voltage via the PWM signal of an Arduino (maybe a convert the PWM signal to analog with a RC-Lowpass and feed it to potentiometer location??)
I recently done this for an industrial application. A low pass filter then use an Op Amp as a follower/buffer to get an analog out. However the analog voltage output will vary from 0 to whatever the supply voltage is....
زس
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Be careful, without a good understanding of the actual specific circuit and also access to the proper schematic you might easily find yourself causing more problems than the worth of it like sending the psu into an uncontrolled oscillation state and causing it to burn out. Search the web for Arduino based PWM controlled psu or such like. There are plenty of Arduino-based example circuits for such a capability.
Rule #1 DON'T assume anything because it makes an ASS of U before ME.
If you want to control this setup with an Arduino, then you will be better off combining the Arduino with a dual digital potentiometer chip to act as a replacement for the two original potentiometers.
You could build or buy a resistor ladder (like an R2R DAC). That would let you control the exact resistance seen by the buck/boost converter. It surely using the pot as a voltage divider to an opamp's input. I don't know if it would be the inverting or non inverting input, but that doesn't matter for our case. You could simply wire up a pot to the board as Scott shows here, dial in exact voltages you want it to work at, disconnect the pot from the board and measure the resistance value of the POT. Now you design and build your ladder, possibly with unequal rungs, to get the precise outputs you desire. You'll want several trimmers in there probably so you can make fine adjustments to get it as exact as you can when you built it. Then by turning on/off certain GPIO pins, you can select exact voltage/amperage settings. Because the precision of the multi-turn POT is very good, and the resolution of your ladder probably won't be, selecting arbitrary settings will depend in the number of GPIO pins you use (the bit resolution of your DAC in this case). I would suggest at least 12 bits of precision as a bare minimum. That would give you 4096 different settings, or another way to look at it, steps of 0.005V (24 volt range)/2.4mA (10 amp range) on your output. It would be hard to get exact values for your application like this (say, exactly 100 mA, or 175 mA), unless you used an uneven rung design. Maybe the first 4 bits chooses a range, and the next 6 choose among exact voltages, and the last 2 move the adjustment up or down by 1% or something for fine precision. I don't know. You'll need to be creative on this, since there likely isn't an exact chip built that will do precisely what you want. That's why you're doing it custom, right?
"this can kill you..........so anyway lets just plug it in!"
I can't even tell you how many times I have taken 110VAC, straight up electrocuted. One time I was replacing an old ladies 3 exterior lights. Her front porch, her side porch along her driveway and her back porch light. I got zapped on the first one. Usually, I can replace a light without turning off any breakers. As long as you are careful, not a problem. On the side porch I went ahead and turned off the breaker. I still received a shock. So on the back porch I flipped the breaker off and disconnected the power supply. I still got shocked for the third time. It was at this point that I came to the realization that the womans aluminum siding was shorted to ground. The entire exterior of her house was hot and ready to discharge to ground. That was why I kept getting shocked. Now, I am no slouch when it comes to electronics. I was an Avionics Electronics Technician in the Marine Corp. And I worked on the AV-8C Harrier jump jet. I even took 220VAC from my right hand straight to my arm pit. I was checking for 220Volts with my Simpson volt meter. My camo sleeves were rolled up and I had my arm pit resting on the coaxial cables for the ANALR-45 radar warning system, 5 cables with metal shielding on the exterior to vent any stray voltages directly to ground so as not to interfere with the radar systems. This was on the flight line at Marine Corp. Air Station Yuma, AZ. It was hot and sweaty, and just as I saw my voltmeter jump to 220Volts, my sweaty right hand slid right down the meter lead and made contact with my hand. I was locked in a death grip as my body tensed up. Luckily, I was able to overcome it in milliseconds, but not before receiving a very serious shock. Thank God the connection was from my hand straight to my armpit. Had I been grounded to any other part of my body, that current/amps would have travelled through my whole body, perhaps even stopping my heart. I still felt the shock all throughout my body, but that was just stray volts wandering through my body seeking ground. Luckily my armpit was making contact with at least 3 of those 5 coaxial cables, giving the electricity many options to return to ground rather than travel throughout my body seeking ground.
Thank you very much for this video. I just built my version of this power supply. Very reliable and powerful. I added a PC cooling fan to my enclosure to ensure everything stays cool. I'll try to post a video soon. Thank you so much!
I prefer linear psu for a lab supply because of the noise
i think that would probably miss the point here. How much would a linear lab psu with these specs cost, diy or otherwise?
@@iikkakonola the video one costos like 30 dólar at least..
@@davidfelipecastroarias8137 I meat that linear psu would cost a ton more than switching power supply. The one built here is switching, and really causes a lot of noise when operated. Linear psu:s are expensive lab quality equipment.
I thought the comment was like if this video was about Audi and someone said I like bugatti a lot better.
@@iikkakonola not really, im talking about other videos of the same, they are a bit cheaper, since the use old psu just modify ing a resistor for a potentiometer u can get a variable one, though its true I havent seen withe the same use if its possible to control current
What gauge wire?
I don't know
@@mmmm768same
wow your english has improved tremendously in a just few years gut gemacht
Love the accent on the "Because I'm such a genius" comment. Great video and a very useful project. I think that I saw a display on eBay that would handle the current.
4:06 *BECAUSE I'M SUCH A GENIUS*
Should your mains connections be soldered, or would it be a better idea to have crimp terminals? I thought generally crimp terminals were preferable, to avoid high temperatures causing connections to break.
stoduk crimping is a good idea
If you need a low current output it's easy to provide an extra + terminal post supplied by a 1k resistor from the normal one.
Crazy how much the price gone down for a ready made power supply. Even a really good one is easy to buy.
Where did you get that enclosure though??
Check this out, very cheap with free shipping cost
(www.aliexpress.com/item/200-175-70mm-Waterproof-Plastic-Enclosure-Project-Box-Instrument-Desk-Case-Shell-With-Handle-For-Electronics/32715590944.html?spm=2114.13010608.0.0.Imm5oj
Mine has delivered safely.. :-)
Ichdar Hsb wow this is amazing! Thanks for sharing this. Now I have everything needed!
thanks!!!!
It is currently less than $9usd at www.banggood.com/Portable-Power-Plastic-Shell-Instrument-Case-Plastic-Chassis-Desktop-Pack-p-1067526.html
You might not want to use it, since the material of this enclosure is made from Polystyrol and does not tollerate much heat. If you ever have any problem, this thing might start burning easily. Better stay away from this Polystyrol case! At 50°C it already gets weak. At 70°C it gets kind of soft. At 80°C it can start melting. Glass Temperature is only about 100°C. And Polystyrol is known to melt into drops that start burning on their own. --- Just put this casing into direct sunlight on a hot summer day, attach a heavy electronic load to it and go for a walk. Do not worry to miss anything, the police will call you anyways after your house was burned down.
Instead you better get something that does not burn so easily!
7:00 " this [Blue] wire represents the positive voltage, and the red wire ground" What-the?? I ain't no expert but I think its the other way around! ;) but regardless, great video!
I really enjoy the way you present your videos. Clear, concise instructions with little to no fluff... as well as just the right amount of humor to keep things interesting! Thumbs up, bud, keep up the good work!
+Kelly Corbridge Thanks you very much.
Hi greatscott! I know this video is very old but I rewatch your videos every now and then because they are informative. Maybe you can do another project like this, maybe an upgraded version because Im really interested in power supplies specially the variable ones.
Would it be possible to use a 12v 5a laptop charger instead of the power supply?
Tyler Anthony yep
I used a Uther netbox
Nice, but i probably would have used a more powerful supply, 12V 10A. Not because I need 10 amps but because I know those chinese power supplies very well and they tend to fail if you use them to their full rating without taking a look inside of them and improving the heatsinking, some solder connections, and sometimes change some questionable capacitors.
If you want a really strong power supply, you could sneak into a hydroelectric damn. If that’s not doable, there should be a little lot in your neighborhood that has all the transformers. All you gotta do is climb the fence and attach whatever cords or wires to it and it will power it super good. Mega power ⚡️ ⚡️ ⚡️ 😊😊😊
@@MrRusty-fm4gb LMFAO
For $70 (on amazon) you can get a 0-30V, 10A power supply, it's about twice the cost of yours, but also gives about twice the amperage, and has an integrated cooling fan (that only kicks in when it needs to). -- Beware though, the Chinese one I got is a bit cheap; mine showed up and I thought the display was bad, I opened it up and noticed that two of the connector plugs were just loose. So I re-tightened them, and now it works like a champ.
Instead of the LTC3780, you can use DPS3012. It has the display and adjustment knob pre-built so you go through less trouble of building the enclosure. It also has higher output current rating, and is only US$34, which costs less than the LTC3780 with separate voltage/current display module and pots/knobs. Use an old computer power supply for the 12V supply and you have a dirt cheat lab power supply that can meet most of your needs.
Thank you whoever you are i couldnt find the stupid display for less than 20€ anywhere
awesome video bud.
can you make a video on how turn an atx power supply to variable bench-top power supply.. thx
Same circuit, but use the atx power supply. Find out the pin layout.
So how do you not die when doing this stuff... like what to avoid doing?
Don't touch mains voltage. That's it.
Thanks. Also, think make a videos about how to make a count down clock with small or large 7 segment displays, and possibly try to do it without an audrino or anything similar to that? (Maybe an audrino for Bluetooth connection or something like that).
Also it would be super awesome if you would include the overall cost of all the supplies in your descriptions. It would help us all know if we can afford to make that particular project.
Thanks, all your videos are super awesome 👍🏿, keep up the awesome work!!!
I have accidentally touched mains like 15 times when i was young. Not pleasant, but i'm still here. You can feel your muscles vibrate violently at 50hz. It was only the live wire though. If you also touch neutral at the same time it will be a bit rougher.
Richard van Pukkem yes, it feels like getting pin and needle if i dont move
It really depends on what mains voltage is in your area. 220-240v can kill you, depending on the path it takes through your body. 120v is far less likely, unless you have heart ailments or something different about you than the average person.
120v still hurts a little, but it's more annoying than anything.
But don't kid yourself. Either of these voltages can stop your heart.
If you don't want to deal with high voltage AC wires, there are power supplies which have a plug just like the one on the back panel, except directly onto the power supply.
These are usually put into servers, so you gotta trick it into thinking that certain contacts are connected by shorting it with a resistor (all external and low voltage work). Plenty of tutorials online.
Wish me luck! I'm gonna give it a shot! The only differences I'm doing are: handmade wooded box, old Xbox 360 power supply(has 12v, 14a output), and adding 2 5v usb ports to it for lights, fume extractors, ect.
Thanks for your great work!
Why didn't you use a VAmp meter that showed more than 3 Amps?
awesomefacepalm im making this one soon, mine can do 10 amp
How to build a power supply: Take a power supply and put it in a case. That's this video in a nutshell.
+ronettreker Don't forget the DC-DC converter and the voltage and current display and the potentiometers and the main switch and.........
+GreatScott! You didn't understand my comment. The Variable Power supply is represented by the 12 power supply and the DC to DC converter. The rest of the parts are just for a convenient form factor. Not even the volt+curent meter is necessary as you could have just mounted two banana sockets in parallel with the binding post and plug a multimeter. What I'm saing is that you focused too much on the package and not on the power supply itself. What's the purpose of this video? Educational? Not really as there wasn't any insight on how a variable power supply works. DYI? Nope. You used pre assembled boards. Hack? No. You didn't even used any common adaptor, you could have used some laptop or pc power supply, something that your viewers might have, but instead opted for a 12V adaptor that you have to buy from an electronics store. Don't get me wrong, some of your videos look like something made by Ben Heck, this one looked more like something made by Kipkay...
It's a simple modular variable lab bench power supply that even beginners can make. I think I said that in the beginning.
+GreatScott! They can't...because they would need to have the money and access to buy those parts from an electronics store. If they had that money and avaible store then they probably wouldn't even bother building one as they could just buy a fully built one. There's a comment bellow me that even asks if it's possible to build one using a PC power supply. You could have used a laptop power supply which would have given you 19V with 4 to 5 Amps. You wouldn't have needed a step up converter as 19V is enough for a begginer. Don't get me wrong, this video is interesting to watch, but useless for a beginner.
ronettreker
Thanks for sharing your opinion. But I have a different opinion concerning this topic.
The most basic DC power supply only needs: a power cord, a container for the internal components, one voltage transformer, diodes, some capacitors for filtering, an adjustable regulator, a heat sink, outlets and I strongly recommend having a switch.
I love your sense of humor.
Variable Lab Bench Power Supply:DIY or Buy
what kind/brand of rotary tool is that? I like it, it looks high quality
Proxxon
I love you man, engineering is your passion .
I know this is an old video, but I can see only one potential problem with the build, which is that you soldered the mains wiring rather than used crimp terminals. I know some places mandate a crimp connection (Here in South Aus, we use crimp and screw terminals for 240v Mains.) Other than that, it's excellent and I do hope it gives you a lot of reliable usage.
But from where did u get the enclosure
Of this project
Exactly
Hello Scott, Good night, I wonder if this variable source can charge lithium ion batteries
Please, answer, Grateful Paul!
Ok, Thanks
At least you didn't let any smoke out!
I just made a variable DC power supply that can deliver up to 32V and
12A. It is made out of (DPS3012 Programmable Constant Voltage Current
Step-down Power Supply Module) and one 400W (36V 11A) LED strip power
supply. I am very happy with the built :)
I just need to have a nice enclosure to put everything inside.
You can try this one to built.
Of course I will share the build once I put everything in a nice enclosure. Here the shipping takes about 2 months to deliver..!!
Oh wow that's a great module. Any suggestions on what gauge of wire to use for connecting the power supply to the controller module?
I used 12 wire AWG.
Thank you!
Wtf the image of the amazon link of the description " 1x 500kΩ Potentiometer: amzn.to/1E6t89w " XD
What the fuck is that picture??
chinese vendors probably
PunakiviAddikti
yeah i know clas ohlson , because i live in finland, but it sucks. better to buy from amazon
PunakiviAddikti
juu, riippu motista jaksaako rakentaa tota
PunakiviAddikti
juu täytyy kattoo, kiitti ku kerroit :D
short question, what bench power supply do you have? (make+model)
ELV DPS5315
Thanks for your quick reaction. Is this a replacement for the one you had before? Did that one break?
he said in the video, it does not make enough amperage, so he may aswell build a new one rather than beefing up the old one!
There is a slight drawback with these kind of small volt/amp meter: the ammeter measures the current on the negative line.
If you have in the circuit (what is powered by the PSU or an oscilloscope for instance) a device connected to the earth, and if the DC 12V supply is also connected to the earth, then, in some cases, the shunt of the ammeter will brobably bee shorted via the earth.
This is harmless but the current will then not be displayed.
this is not electronics, this is crafting :)
Is there any way to make one out of a real PSU (like an old computer power supply)? I recently began *real* electronics learning, and having a variable power supply would be a nice addition.
+Said Kharboutli yes, i guess, but then you need the lcd display to handle 30A at least
+romantashev You can buy 100 amp ones for a few dollars, the inductor type. 10 bucks for a shunted meter.(~60 amps, better accuracy)
Richard Smith Mind linking it? Quickly searched through Amazon and couldn't find anything for that low of a price. Thanks.
+Said Kharboutli something like that? www.ebay.com/itm/DC-4-5-30V-0-50A-Dual-LED-Digital-Volt-meter-Ammeter-Voltage-AMP-Power-Hot-TXCL-/301775576961?hash=item464339df81:g:0OMAAOSwo0JWKHge
Shunted:
www.dx.com/p/100a-3-digit-display-panel-digital-ammeter-w-shunt-resistor-black-dc-4-30v-163498#.Vkm7HXarT1s (Don't believe the 100a claim, its closer the 60a)
Inductor:
www.dx.com/p/5-5-x-3cm-lcd-2-in-1-dual-display-3-digital-ac-voltmeter-ammeter-meter-black-ac-100-300v-235989#.Vkm6kHarT1s
Great as a learning project or for bragging rights but I rather buy a commercial version. 30V 5A sell for $40 on eBay.
Ah but see the browny points you get for building your own ^^
only works if you're gay. Building electronic devices isn't going to impress any girl.
Maybe if you build a vibrator for valentine ( ͡° ͜ʖ ͡°)
Alkéryn ( ͡° ͜ʖ ͡°)
Everyone should realize that switching power supplies and DC-DC converters put out RFI, radio frequency interference. It's not very much, but it can cause some circuits, especially audio, to pick up interference. So it's important to put a filter choke and low ESR capacitors between the converter and the output.
I HAVE WANTED/NEEDED ONE OF THESE FOR SO LONG IM SO HAPPY I CAN MAKE IT!!!!
No reason to shout, though.
I really would like to find that exact enclosure do you have a link to it
+1
Check this one out, this is the one I used for this project and a few others!
uk.rs-online.com/web/p/instrument-cases/7733274/
That exact same enclosure for anyone interested can be found on banggood.com, in fact there are two identical ones for a slightly different price. The cheapest is £7.17 the other is £7.97 (go figure) at the time of writing (Dec 7th 2016). The Banggood site allows you to choose shipping destination and currency so you can select whatever you want/prefer. The direct link to the lowest price one currently is www.banggood.com/Portable-Power-Plastic-Shell-Instrument-Case-Plastic-Chassis-Desktop-Pack-p-1067526.html?rmmds=search
Also I'd already decided myself to use the same technique and I purchased a 48v 5Amp switching supply that should adjust to 55volts to use as input to one of these: www.banggood.com/DPS5005-50V-5A-Buck-Adjustable-DC-Constant-Voltage-Power-Supply-Module-Integrated-Voltmeter-Ammeter-p-1062473.html?rmmds=search
A voltmeter, ammeter, power meter, current and voltage limit setting and colour LCD panel complete with control knob and on/off switch for £22.22 so everything will fit in one panel cutout roughly the size of just the display in this video.
Just add the output terminals. You get a proper 0-50v adjustable supply too. Total cost of 48v switch supply, psu module and case ~ £50 plus some minor parts most of which are already in my parts bins. You can't buy a commercial unit with those specs anywhere that I've found, and in addition if you want a double or triple unit it would be simple to create, needing only a marginally larger case possibly although a double unit would almost certainly fit into one. If you want 5A but don't need more than ~30volts they have quite a nice looking commercial 0-32v 0-5A bench unit here:
www.banggood.com/CPS-3205-0-32V-0-5A-Portable-Adjustable-DC-Power-Supply-110V220V-p-934530.html?rmmds=search
I plan on also having building an inductance sweep tester and zener tester in the same case especially as the latter will require 50 volts DC to cover most gen purpose zeners including power types. Hope that all proves useful.
Bob Lewis Thanks, definitely worth checking out when I get to designing my PCB
I've just ordered a case so with a bit of luck it might arrive by Christmas! I already had the SMPS and the variable Power supply module.
Ich weis man soll hier nicht deutsch schreiben aber da ich jez grad nicht die Lust habe es zu überstzen schreibe ich es jetzt so . Ich gehe stark davon aus dass du ein entweder eine abgeschlossene Ausbildung al Elektroniker hast oder dich noch in ihr befindest( wie ich ) ich bin echt begeisterst was du hier alles auf die beine stellst und deine effizienz ( was man z.B an heißkleber sehen kann ist billig und geht schnell). Ich werde mal deine Patreon Kampanie unterstützen. Aber ich habe einen kritikpunkt und zwar die verdrahtung. Bitte verwende keinen grün gelben draht mehr für ground oder plus das ist wirklich wirklich gefährlich wenn jemand anderes das gerät in die hand nimmt. Und arbeite bei earth bitte mit ringkabelschuhen oder ähnlichem da diese das ganze noch sicherer machen das wäre mir ein anliegen. Machs gut danke für deine arbeit and i see you next time ;)
Elektroniker für Betriebstechnik und Ingenieur für Elektrotechnik bin ich. Und deine Anliegen sind gerechtfertigt. Jedoch durch mein Produktionsbudget und Zeit nicht immer einhaltbar.
GreatScott!
Alles klar cool. Wo hast du dein Studium gemacht FH oder Uni
TEAREX alias. Paprika
FH
+GreatScott!
Mit der Begründung solltest du dich vielleicht an deinen eigenen Tipp halten und die Finger von Netzspannnung lassen. Budget und Zeit sind jedenfalls keine Gründe den Potentialausgleich _so_ auszuführen.
Zumal du ja selbst sagst es sei Sicherheitsrelevant...
+TEAREX alias. Paprika Vertraue keiner Verdrahtung, die du nicht selbst gemacht hast. )
im addicted to your videos!
That voice tho
lol
I would add an insulating boot around the mains inlet connections to improve safety. For example a wire or chain could be inserted into the vent slots to touch a live terminal.
There is no link for the enclosure... or did i miss something?
Enclosures can be whichever you want long as it's big enough to hold every thing.
Where is the case from?
+SlyTrickyGaming Conrad
+GreatScott! Thank you
+GreatScott! Not sure what Conrad means when it comes to the case -- is there a model/part number I can search or a web site? Thanks
+Barry Stevens Conrad is a German electronics store. Im not sure if they ship to other countries, but i found these on their website: www.conrad.de/de/Search.html?search=gss0 I hope that helps you. :)
Wasn't finding anything I liked anywhere. If they don't ship maybe I can get a part number. If all else fails I'll build something -- Thanks
your voice is always clear to understand ......
I follow your instruction but:
1. I use a 180W 12V inverter instead of the 60W you use.
2. The LTC3780 Max power is 130W, since I can't find a 130W fuse anywhere so I use the closest thing I have which is a 125W fuse, I added the 125W fuse for overpower protection.
3. I added more heat sink and a fan for more cooling because the data sheet of the LTC3780 buck/boost regulator said that you need more cooling if the power is above 80W.
I just bought a cheap lab bench power supply and adjusting the voltage is a pain in the ass.
Love the makeshift power resistor on the background at the end ahah
i dont know if its just me but i was thinking there was so much space left and that only makes the power supply so much bigger but great video and quality as always
For that kind of current it's important to have a thick and short cable for the output terminals; otherwise the voltage regulation could be noticeably off. And I would solder them too, replacing the screw terminals the same way we did with the potenciometers. I'd also avoid hot glue since it tends to 1) unglue by itself and 2) melt in the presence of heat. I also second other people's opinions about heatshrinking the AC terminals and using a better solution for the Earth protection, like making a small ring with the cable end and a little bit of solder so it wouldn't come off of the screw.
For security reasons, you should use crimped wires instead of soldered ones. Can even save some time doing it. ;)
Thank you Mr. Arnold!
1 major thing this Power supply does not have
Current limiting feature
This means if your circuit draws alot of current (like shortcircuit), then the power supply simply dont care it keeps supplying the current until your circuit explodes
My atx computer power supply died so now im going to make the power supply in this video
I built it! Destroyed the pads for the CC pot but I did it!
This is a great project and the power supply works a treat. Watch out for the UK Amazon power supply; it's much bigger than the one that features in the video (10Amp and physically larger) so there might be issues when fitting in an enclosure.
when i was building this i got AC Input part and it looked a bit odd so i tested it but because i am such a Genius i forget to unplug the plug FROM MAINS so i pluged it in and i was hold both terminals cuz forget it was plugged in and i got the shock of my life luckily the Circuit breaker cut and i lived.
I made one out of an old ethernet box that had battery charging circuit in it and it works great
Bro, hold the terminals when you torque down those screws! Had me cringing thinking the solder joints were about to snap 😂 Awesome build though!
Grounding is a very important safety feature. This properly grounded power supply, includes many bench top power supplies can also easily create very dangerouse deadly electrocutions, can destroy test equipment, and can destroy devices being powered giving the user a dangerouse false sense of security. For testing using truly isolated power supply is far safer, far less risky that will help protect you and saves your devices being powered and test equipment. This power supply is not isolated so be extreemly careful if used for trouble shooting and testing. .
4:05 I was hoping you would say "..but it is okay, I have many tables."
Hello Scott I think you missed something very simple and must in every circuit, that was the fuse.
Also as an upgrade you can also include reverse polarity, short circuit. Which I think you have already included in another video