DC Power Supply from ATX power supply
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- čas přidán 17. 01. 2014
- Here is a quick video on how I turned an old ATX computer power supply in to a nice DC power supply that gives 3 v, 5 v, and 12 v at good current ( 10 amp and more) plus other voltages (23 v and 15v) at about 500 mA .
I've made several of these and I always find new uses. I usualy get the ATX power supplies for free. I look at it as a re-cycling project to keep electronics out of landfill.
You can see that I added a ammeter and a variable resistor to measure and control the amount of current I am using.
I use the DC power supply to charge Li ion batteries scavenged from laptop power packs.
I usually find of the 9 a or 12 cells, there may be 2 or 3 that are no good, but the rest are OK. I use these good cells to re-power cordless drill and flashlights. They are much better than the Ni Cd cells, hold more charge and do not self discharge when stored and do not have the so-called memory effect of Ni Cd cells.. - Věda a technologie
You're a legend... thanks for sorting the colours for us, without waffling. REALLY appreciate your time and effort on this!
Very useful informative video.
As you say, the ATX modules can be obtained very cheaply from a scrap PC tower cabinet.
Nobody needs to be without a working bench DC power supply for their projects.
Thanks for sharing your thoughts and perspectives. I appreciate your unique designs.
Very much appreciate you taking the time for this teaching demonstration.
Very nice explanation.. thank you.. This is the first time that I understood a little bit more regarding the -12v and its use. I didn't fully grasp the concept before.. I will look into a bit more on this but a Light came on thanks to you. thanks again.
Clear and Best explanation ever!!!!!! Thumbs up!!! !
you are lucky to have sooo many power supply units
Really useful information with talk-though, so much better than the common music video with minimal information.
Great video, thank you!
This is very interested . I will try this
very nice work ..... thanks
After some back and forth with some people, I decided to make another video explaining the various voltage combinations that you can get from the ATX power supply
Do a You Tube SEARCH on
VOLTAGE COMBINATIONS FROM ATX POWER SUPPLY
I tried to paste in the URL directly to that video, but Google doesn't let me paste into this text box
czcams.com/video/iahc1puHUxs/video.html
Excelente amigo
THANK YOU MUCH
very nice
Thanks for the reply. The 12v rail is rated 42amps. I'm pulling 15amps and it's shutting down.
It could be that the rating is not for continuous current draw such as what you are doing to charge the batteries. I can see that internal capacitors are OK to draw that amount of current ( 42A) for a very short period of time eg when a Hard Drive starts to spun up, along with the CPU booting up.
Thank you
I enjoyed the video
Do you have any idea on how to adjust the 12V rail on the ATX power supply. My idea is to make the power supply adjustable.
KInd regards
the ``Keepers`` are called Zipties... just helping here !
Great video. You say the the 60 ohm resister is not needed but it is useful. How is it useful? Other videos say it is needed to make the voltages more accurate. Thanks
i want to use 24v from atx, but my load is also uses +5v at the same time, if i use +12v and -12v to generate 24v than the ground and -12v goes commonat the same time,, any suggestions to get 24v
well explained, god bless you
Thanks for the support. I'm still active but have fallen behind the current video technology
@@disproman Can I ask you, what are the grey and purple for?
@@MrZeriouhradi I think they are used for internal monnitoring, but I don't know for sure. In any case they are not useful for the power supply . I've never used the,m.
@@disproman thank you
Great video, very helpful, I rescued one of these from an old desktop thinking it will come in handy one day. Now I want to make a hot wire cutter for foam carving and thought this would be just the job only problem is I didn't know what all the wires were for or where to start. You've explained it perfectly.
Just one thing, what are the grey and purple wires for?
They are not used for the power supply - they are wires for sensing points on the motherboard of the computer. You can cut them off and tape the ends.
disproman .
Since post the video, I've had a number of pals ask me to make up a power supply for them -. They use it for rust removal by electrolysis or as it's sometimes called "spooging". Yes, I know it's a weird term but that's what they use.
I do this all the time now. I tend to use ones that stink of cigarette smoke as nobody wants them! Done 50 this week! Bang em out for £15 a unit!
One of the best examples of recycling. Your units will probably be in service for longer time than when they were used in the original computers.
Thank you great video,does it matter which of the black wires you join with the green?
No - doesn't matter - choose the smallest diameter wire and it will work just fine.
i want to charge my car bettery with computer power suply. But in power suply there is a yellow color wire having voltage is 12v thats ok,,, but ampere is low as about 1ampere to 2ampere only (which is not suffient to charge my car bettery). My problem is that how to increase the amperage of (yellow 12v wire) so that it charge my bettery easily.
regds,
thanks. plz reply in detail to solve my problem
Thx...I received a Astec power supply but no instructions in the box. Needed to turn it on.
To turn the power supply ON, you should join the green wire and one of the black wires.
In my power supply, I use a small switch to do that so I can turn it ON or OFF
Any small switch is OK - it caries only a few milliamps of current.
❤❤
Thank you for sharing this video. I do have a question how many amps will be in the dc5 and dc12v ( out put off the switch off each)
The name plate on yur power supply will show the maximum current that you can get from each of the voltages. This maximum is available if that voltage is the only one taking a load.
The nameplate also shows the total power available so, if you are using more than one of the voltages, then using Ohm's Law you can determine the maximum current for each of the voltages you are using.
@@disproman thank you very much. I did all what you have show on your video. And i got everything great. But the 12 v i got it 11.56v after your knowledge what i did wrong???
You have not done anything wrong.
It may be a combination of several things.
A slight error in your voltmeter - most digital voltmeters have at least 0.5V error and analog meters may have up to 1.5 V error PLUS
a slight error in the internal voltage reference of your power supply ( could be 0.2 V ) and you'll see less than 12V.
Almost every application that uses 12V for its power, will tolerate at least 1 V higher or lower - many can tolerate 2V above the nominal 12V power. Many applications will be OK even with 10V.
If you need very precise voltages, then what I suggest is that you can get a voltage reference chip that will calibrate your voltmeter. Something like
'www.maximintegrated.com/en/products/analog/voltage-references/REF01.html/tb_tab1
You can then calibrate your voltmeter, and see the effect of the lower voltage on your application.
Yu might also use another ATX power supply and see if there is 12 V on the yellow wire outputs.
As a last comment, try out the lower voltage and see if your application works OK, if it does, then - GREAT !
@@disproman thank you for those explanation. It was very helpful
can you tell me when you bundled up all the 12v,5v, and 3 volt wires is this to get more amperage ? or why was this done?
Yes, I wanted to get all the power that the supply can deliver.
In most applications this is not needed but for example, when I'm using electrolysis to de-rust tools etc, it needs up to 15 A on the 12V output.
And yes, it is some extra effort to make all those wires fit together, but when I need the power, it sure is nice to have.
I only need to do this once, and after that I've got plenty of power to use.
So if your application doesn't need the full power, you can get away with connecting fewer wires together..
My friend your idea is awesome let me ask you a question do you think that can run and inverter from 12 volts to 110 volt inverter
Yes it is POSSIBLE, but it is a bit strange - if you have 110V input to the power supply why are you then connecting to an inverter.
But if your input is 220 V then I can see that the inverter might be useful to get 110V .
This could also be done with a step down transformer ( 220 to 110 V). But the power that you
want might make the transformer more expensive
I want like a higher voltage, if that makes sense. It claims input of 100-120 to output of 200-220. How is it 5v, and 12v cables now?
Most ATX power supplies are designed to work on either 110 V or 220V.
The is a small red switch on the back of the power supply.
BUT . . . do NOT try to operate a 110V setting of the switch with 220V - it will destroy the power supply.
If you need higher voltages, there are boost circuit packages that will let you get higher voltages
Here is an example
www.creatroninc.com/product/4-35v-3a-adjustable-step-up-regulator/
Try taking the resistor off completely.
The green connected to any one of the black SHOULD turn it on.
If that doesn't happen, it usually means that the power supply is no good.
I assume there is no other ON OFF switch on the power supply.
what if mine powers on and shuts off immediately
That usually means that there is an internal overload and frankly the best strategy is to get another power supply.
You can open it up ( making sure that the 110V AC is not connected) and see if there something physically evident - but usually it's one of the components. It's not worthwhile to see if you can find and fix it at that point
I have 3 identical power supplys. The 12v rails on them are rated at 8 amps. one thing I noticed is if shorting green and grey or black without cutting the clips off the PSU would power on. Once I started cutting off the clips and grouping the wires the PSUs would power on and die immediately. After many hours of messing around I found out that shorting green and ground AND brown and grey makes them power on as normal. I was hoping you could offer some explanation.
I suggest that you only use the green and black wires to turn the PSU on. That's what the computer motherboard uses to wake up the PSU.
How much current does each of the yellow 12v wires handle? Must you bundle them all together like that?
I have not measured the current on each yellow wire separately.
I bundle them together simply because I want the maximum capacity from the power supply .
I expect that in some low current applications of the power supply, you could use one or two of the yellow wires.
The wires are 16 Guage which is nominally rated at about 3 A - but that is a MAXIMUM. At that current the wire WILL heat up.
I personally do not like it when wires start to get warm - it's usually a sign of trouble.
nice explanation ! i found a few old computers at the city landfill,took out the power supplies and got them all working as bench tops. Now i was wondering if i put the 3 volts and the 12 volts together if i could successfully use it to charge a car battery .probably going to try it this week. any thoughts.
+vic mon
To charge a 12V car battery, you'll need about 14 - 15 V.
The only way to get that is to use the -12V and +3V connections.
The challenge though is the the -12V is limited to about 1/2 Amp ( 500mA) so it might
take a while to get a full charge. But it should work if the battery is not totally discharged.
If you connect the +3 and + 12, you'll get 9 volts - the difference between 3 V and 12V.
You'll need about 14V to actually charge a 12V car battery.
You can get a MINUS 12V from the BLUE wire - but it's only good for about 0.5 Amp or so.
To charge the battery, use the -12V BLUE and the PLUS 3 ORANGE to get a 15V difference. IF your car battery is not well charged to begin with, your ATX power supply will be overloaded and will shut down.
To prevent this, you'll have to put in some amount of resistance ( 2-4 ohms) to keep the current below 0.5 A. The resistor must be able to handle at least 5 watts.
I have a DC pump that I use for pumping oil. do you think I could use a computer power supply to run it? I figured since it hooks up to my 12v battery that it might work with the 12v power supply. it uses 13.5 amp. I have an old AT power supply that I want to try. it has an external on/off switch with a white, blue, brown and of course black for ground. wire harness has Black (ground), Yellow (12V), Red (5V), Orange (Power Good), Blue (-12V) and White (-5V) I believe. does this sound correct? do I need to put in resistors for an AT power supply? ty for your assistance. 🙂
Your power supply will be working close to its limit. The in-rush starting current might over load the ATX. It depends on your particular unit.
If it does over load try the 5.5 V output
The over load does not damage the ATX - it simply goes to sleep.
How would you connect a digital volt/amp meter so it would read the voltage and amps output of the 4 different voltages outputs (3, 5, 12, -12), without moving the digital volt/amp wire from each voltage output post?
Hope that was clear enough on my question
Well, first, you KNOW the voltage for each of the wires - the internal circuits are quite precise for that, so no need to measure them.
As for measuring the current (amps) you'll have to have an ammeter for each of the outputs - here I assume that you are feeding power from more than one of the outputs.
However, if you only use one of the outputs at a time, then, simply connect the ammeter in series with the output you are using.
You can see in the video, that I have a number of binding posts and I have labelled them so I know what voltage I am using. The wires I connect then go to the ammeter on the front panel. But I only use one voltage at a time.
When connecting the green and black wires to keep the power supply running, my power supply turns on for approx. 2 seconds and turns off. What would cause this?
Make sure that none of the other wires are touching each other.
A short circuit usually causes the power supply to shut down.
That's one of the nice things about these power supplies - if there is an overload , it shuts down rather than destroying itself.
Alternatively, the power supply has an internal defect or short circuit.
Take the supply out of its metal box, and gently cleaning off the dust and crud with a soft brush ( of course unplug from the 110V first)
If that doesn't fix it, then it's likely it is no good - cannibalize it for the parts and re-cycle the rest..
There IS one green wire coming out of my Dell mm720 PS leading to the largest harness that has a mess of other black, red, orange, white and purple wires. How does one know which black wire to join with the green to turn in on? Would it be one of the black ones in that harness? There are 9 other black wires in that harness, which is clearly the main harness that attaches to the motherboard. The rest of the bundles coming out are 4 and 5 wire harnesses labeled p2, p3, p4, p5 and p6. (the main harness is labeled p1)
You can choose ANY of the black wires. They all terminate inside the power supply at the same point ( electrically) .
I typically choose the smallest one since there is very little current ( milliamps) when you turn on the power supply.
I also use ALL of the black wires as my 0 V so that I can get the maximum current with ay of the voltages.
i see that you have the blue lead/ neg 12v so that you can get higher/different voltages in combinations. i am building my first atx bench psu, and don't quite understand the concept. i thought +12v and neg 12v would cancel out. i can kinda see the volt difference of 23v with 0v creating the lack of normal addition, but i'm not getting what two leads/banana posts are in play. is it the positive /red lead on the +12v and the neg 12v as the neg/black black lead causing the 23v difference where zero is a place value, and the neg 12v post becomes the common/neg/ground?? and then all the other combinations are based on this same concept?
good video though, if my last couple of thoughts/questions are on the right path then this is the first video that helped me get to that point. thanks
that's strange when i type /-12v youtube draws a line through everything after the negative symbol...
Well, Partick, you are sort of the right track.
The +12 and the -12 do not cancel each other .
So, it is possible to get many other voltages by choosing other combinations.
For example ( staying with the OV +3.3V + 5V and the + 12V )
you can get a 7V - the difference between the +5 and the + 12.
Or you can get a 1.7V difference between the +3.3 and the +5
SO now you can see the difference between the +12 and the -12 is 24
Or you could get 17V ( the difference between -12 and +5)
The best way to visualize this is to draw a vertical line. Put a mark in the middle of the line which is the 0V. Above the line mark the + voltages and below the line mark the -voltages. You can then see all of the combinations as the DIFFERENCE between any of two marks.
The only restriction is ow much current you can get - for example, the 24V ( that is the -12 and +12 combination) is limited to the current available from the -12.
This is usually about 0.5A
Great explaination, thanks. I got the difference in volt =total vokt now.
But HOW do I combine the negative 12 and X volt (mechanically, say I've got a red probe banana jack in one hand and black probe banana jack in the other)
Or
Do i just tie a jumper rail from the +3.3v/+5/+12v to the negative 12v Then plug in the banana jacks》 red +, black -
Hmmmm - I wish I could add a picture here - it would be worth 1000 words.
Give me a day or two and I will post another video showing the set up.
+disproman you rock!!!!!
Just want to make sure I'm getting this right you put each color as one wire each & then do the same to the black wire & use each color as the + & the back as the - to get the power you want from each of the color wires?
Yes - I group each colour together, as an example, for the +12 V , I group all of the yellow wires together, and solder them to one terminal. This means that all of the current available on the yellow wires (+12V) is available to my application.
I also group all of the black wires together and make one terminal for the 0V reference - that's a bit of a pain, because there are so many of them, but I find it is worth the work to do it.
I used a 450 watt PC supply to power my 20 watt ham radio transceiver. I noticed on this power supply that there were 4 separate groups of black wires...so, i used one wire out of each little group of black wires and soldered the ends of them together to connect them to the output for my rig and wrapped the unused black wires and folded them back out of the way. It seemed to be a convenient way to use all 4 groups of black wires without having such a large external bundle of wire to deal with. One problem is that it only gives me 11.6 volts to the buck/boost device i need to give me the 13.7 volt input needed for the transceiver. Is there a way to up the voltage by a modification to the power supply board. Thanks for the info, it eliminated having to use a battery and charger when set up in the shack.
Unfortunately, the power supply is designed to provide 12V and is used to power the motherboard - it is not an automotive application.. It usually is within about 0.2 V . You might need to verify the calibration of your voltmeter - there are neat voltage reference chips for that.
steelcityelectronics.com/2015/11/11/analog-devices-ad587-10v-reference/
The so-called 12V automotive is really 13.4 to 13.8 V or could be as high as 14.5 - 14.7 V DC. Those voltages are not available form the standard outputs of the ATX power supply.
I suspect that every power supply manufacturer has their own innard design and proprietary approach so any modification would be unique to each design. So long as they comply with the output voltages ( and a few other parameters) no one cares how they do it. I have not mucked around inside the ATX's that I have.
Now if your transceiver is a 20W, and assuming about 15% efficiency, that implies that you need about 150W, or about 12-15 Amps at 12V.
You might be wise to use all of the black wires - I know that it is a pain to do that , but it will certainly ensure that you are getting all the power that is available from the ATX.
@@disproman ? I was under the impression ( read- assumption) that, as the black wires are all ground, there wouldn't be any benefit to hooking 2 or more together. I applied this assumption to all the wires, i..e- hooking 2 yellows together and 2 blacks would not give you more 12v amps, you'd just have more wire clumped uo with the same output.
But if I understand what you said- doubling up the grounds will increase or at least ensure that the max amperage from the power supply is available??
* And if so, is there anything to gain from doubling up the hot wires or is it strictly ground wire magic? Thanks for the info ive already gotten here btw
Each of the individual wires are relatively small guage wire eg 18 guage, which are rated for a maximum current of about 1 amp.
If you draw more than that, eg 20 amps on the 3.3 V connection, then the wire will overheat and maybe start melt its plastic insulation if you only use one of the wires.
When I made this version of the ATX power supply I was doing things like electrochemical rust removal, where I would draw the full current at 12V.
So I took the time to use ALL of the wires. Yes it took some more effort but then I HAD the full potential of the power supply available to any use.
May I know what you used to solder all the wires together? A problem I face was there were too many wires to solder to a single binding post.
I faced the same problem - especially for the black wires . There are a lot of them..
Here's what I did -
For each colour of wire, eg black , I cut them all to the same length.
I then stripped the insulation off about 1.5 in or about 4 cm.
I then twisted the bare ends all together. For the black wires I made 2 "bundles" of wires.
I then soldered the twisted bare ends for each colour wire into 1 "glob"
You might have to use a bigger soldering iron for this. I also usually put some flux on the wires to help
get the solder to flow.
I them made up a strip of metal - could be from a tin can, or some thin galvanized sheet iron, about 1 in long
( 3 cm) with 2 holes - one at each end.
I then soldered the soldered wire bundle into one of the holes.
I used the second hole to connect to my terminal.
If you look at about 3:30 of the video you'll see the soldering and the metal strips - in the video I had some thin copper sheet , but the metal from a tin can ( not aluminum) will work OK too.
It might seems like a lot of work but I found it's well worth the time because you'll only do it once.
Thanks! That's a really detailed reply. I appreciate the fact that you took time off to do that.
I have tried to make this work, but do not get any voltage from any wire except the purple. I have connected the green to black with no results. I tried hooking a 10ohm resistor between red and black. Still nothing ! This is a new PSU. Any ideas?
Assuming that your power supply is not "dead on arrival", about the only reason that I can think of, at the moment, is that somewhere, there is an overload ( not a short circuit) on the power supply.
An overload usually makes the power supply "go to sleep".
The remedy is to clear the over load, unplug the power supply from 110V power, wait several minutes, then plug in again. The power supply will not be "on" yet.
You then should be able to get the power supply to start up, by connecting green to black.
A short circuit will cause the internal fuse to blow. To replace the fuse, you'll need to remove the power supply from its case.
I have a new power supply I want to run a car stereo off the 12V only. Can I just tape off all the other extra wires or do I need to put resistors on them? Also what are the purple and grey wires?
You can simply use the 12V wires ( yellow and black) and tape off the other voltages.
You don't have to use a resistor since your power supply is a newer one ( the older ones i.e. 1990's needed it for stability).
You should make sure that you power supply and the radio have some venting - if they are in a sealed box, they'll probably overheat. The exhaust fan on the power supply should be OK to draw in cooling air for both radio and power supply.
Sweet, thanks for the quick response
I scavenged a laptop battery yesterday, I'll try to charge it as it is first. I wonder for how long that would take with 12.5 volt, 30 amps.... Do you take yours apart and charge the individual cells? If you put all the yellow wires together, do you get more amps out of it?
You can try to charge the laptop pack as is - but if there are dead cells inside, the ones that are still OK, will not get charged.
The usual reason that people give their laptop packs away is that there are dead cells inside and the whole pack won't charge up.
That's why I take the pack apart ( carefully)
You can try to do it - BUT . . BUT BE CAREFUL ABOUT HOW MUCH CURRENT YOU ARE USING.
The recent examples of battery packs burning up shows what can happen when you charge the pack with too much current.
I'd stick with charging current of 0.5 to 0.7 Amps - may take more time but it won't burn up.
To get the maximum current off the yellow ( 12V) wires, you HAVE to use them all .. If you only use say, 1 or 2 Amps, on your experiemnts,. then using one or two wires will be OK.
For 30A - you've gotta use them all.
How to conect a psu to a laptop with out adjustments on the psu?Which wires and colours are need to power a laptop?!
Unfortunately, the DC connections to laptops, are proprietary to each manufacturer. And even within a family of laptops from the same supplier there are major differences.
This is quite unlike the standard for ATX power supplies that was agreed to over 20 years ago.
It is possible to figure it out however.
You would have to determine from the battery of the specific laptop, what output connections on the power connector have what voltage. You can them see if the voltages correspond to the voltages available on the ATX PSU.
But note that there are connections for temperature sensing, that measure the internal temperature of the battery pack as well as DC voltages. SO you would have to figure that out as well.
In addition you will have to have a proprietary connector that would let you attach the ATX PSU to the laptop power input.
That kind of project will involve some creative hacking. I personally have not seen anyone do it.
-12 blue + red 5v
my friend thank you for the response
The reason why is because right now I have a battery charger charging 6 batteries I use the inverter a husky 750 watt which I powering my TV satellite modem Wi-Fi an Xbox in one room and 5 fans around the whole house and That's All day long I've been running like that for the last 3 months and your idea looks more practical electrical pole then a battery charger but it's the amps that worried what would you think what do you recommend
I still do not understand why you do not power the equipment directly from the 110V power.
If you only have power for some of the time, then power the equipment directly, AND charge your battery. Then when the power goes off, you have a fully charged battery.
Doing it the way you do now, will decrease the life of the battery.
A fully charged 12 V lead acid battery should have between 13.7 and 14.2 V .
Are you in Puerto Rico ? Do you NEED all 5 fans to be running at the same time? They are probably the biggest load on your battery. All of the other stuff together probably uses less than 1 of the fans.
Sir,
Did you used all the wires (like all the black wires and all the red wires) and connected them together?
Yes, I used all the wires of each colour.
I removed about 1 1/2 in ( about 35 mm) of the insulation , twisted the bare wires together and soldered them into one big "lump" of wire. That was I get the full benefit of the power supply.
You'll need a good soldering gun to get them all done together.
I know that some people don't use all of the wires of each colour.
But there are some uses of the power supply that draw 8 - 10 A ( eg electrolysis for rust removal, flood lights from car headlights etc)
+disproman wow nice information I get here :D thanks man, I was thinking to use just one of each other but you have changed my plans :D
Very cool, but where did you get the resister(seeing as how it doesn't look new out of the package).
I had it left over from previous projects about 10 years ago.
You can get them at Sayal Electronics, or an electronics surplus place.
In most power supplies the resistor is not needed, but some of them DO need it to stabilize the output.
Try making the thing without the resistor and see if it works .
Thank you.
So i tried this but failed. I got a 725w psu. its a single 12v rail with a Max output of 42amps. When i put a 15amp load the voltage drops to below 8v then shuts down. I'm using it to charge some 7.4 lithium batteries. I don't know why it's dropping and not staying at a constant 12v. I did every thing in your video plus had a +3.3v sensing wire that i connected to one +3.3v wire and a gray vs wire connected to a ground wire. I did that only because on it was like that on the mainplug
If you are getting that kind of voltage drop , that is down to 8 v on the 12 v output, you are overloading it quite a bit. The power supply is doing what it should - it shuts down before things internally burn up. Putting that much current into a Lithium ion battery isn't a good thing. You might try limiting the current with a resistor in series with the battery.
The resistor can be in the range of 3 ohms, but it will have to handle the current. I made one from some nichrome wire using a DVM ser to R to figure out the resistance. The resistor will get quite hot. I also suggest that you use a DC ammeter to measure the current you are taking from the power supply ( if you aren't dong that already). Making a DC ammeter from an analog meter movement is straightforward.
I usually limit the lithium ion batterys that I recycle from laptop battery packs to about 0.1C where C is the capacity in mAhrs eg C=1800mAhr, charge at 180 mA
I found that the Battery University to be an excellent source of information
batteryuniversity.com/learn/article/charging_lithium_ion_batteries
Great Video! What combination of wires do you use for electrolysis? I will be doing a cast iron table saw top, so what do you recommend?
I use the 12V supply fro electrolytic rust removal.
Most supplies should have enough capacity to do the job..
I usually see about 5 to 6 Amps of current. On your job, there will be higher current . A smaller power supply simply means that it will take longer to remove the rust.
The trick with the rust removal, is to periodically stop the process, and clean off the crud on the sacrificial electrodes. Sometimes, I wash off the black stuff on the object as well.
I also found that having many sacrificial electrodes that a placed so they are in direct "line of sight" with the object helps a lot.
The worst part of the job is the final cleaning - the black coating has to be scrubbed off, under running water then dried quickly so it doesn't re-rust.
Thanks, I figured so. Just want to confirm. Would it be possible for you to post a schematic of the two power supplies in your video? I would appreciate it.
I do not have any decent video editing s/w so I'd have to make a new video and post a link to it. I'll be out in the bush for the next week or so - Internet-less.
Would you be willing to do a drawing schematic and send through email?
I'd prefer to make the new video so everyone can see it.
Might take a bit longer but worth the wait -
What black wire is needed to wire up with the green wire? Just any black wire from the bunch? Nobody ever explains which specific single black wire pairs with the green wire. Thanks.
Any one of the black wires will work.
That's because the all black wires are connected to the same terminal inside the power supply box.
The same applies to the other colour wires.
That's also the reason that I group them all together by colour. I usually select the smallest (thinnest) black one to connect with the green one because there is almost no current going through it.
So, why are there so many of these black ( and other colour) wires ? They are needed at various connections to the motherboard, hard drives, accessories etc etc in the computer.
Great question and answer. That was also my question.
I have tried to experiment but when I touch with battery's terminals it's fan non-stop running with out connecting with AC power.let me know what happened and how to resolve.
I think what is happening is that your battery is back-feeding the fan . It will drain your battery if you leave it connected this way.
I recommend that you always power up the power supply BEFORE you make any connections to a battery or other device.
And you will notice from the video that I have a built-in ammeter to measure the current to make sure that the power supply is providing power .
dude!!!
And are all the black wires necessary? Is it possible to narrow it down into 1?
Yes, you can certainly use only one black wire, but significantly reduces te amount of power that will be able to draw from the power supply.
Most supplies can make 250 to 400 watts, but with only one black wire, that will be limited to 20 - 25 watts.
More black wires = more power available
@@disproman oh, well thanks for the reply. I just felt that putting multiple wires together just because they share the same color was a little ridiculous and could be dangerous.
do I have to use the blue for my remote for my car radio or not
Reply
The blue provides a neg 12 V with a limitation of about 200-400 mA. measured to the black wire.
I think your remote needs plus 12 V , so simply use one of the yellow wires to get plus 12 V
Make it out of the bush? Waiting for the video?
I think you missed mentioning what the Grey and Blue wires are for. Thanks.
The blue wire is for a -12V , and gives you 24 V power, but at at a very much reduced current - less than 1/2 Amp, compared to the other voltages which provide 10's of Amps of power.
The grey lead is not used in the power supply hack.
This was covered in some of the discussion but is well worth repeating.
Can I use ORANGE +YELLOW to get 15V for charging a battery?
No, that will not work.
Please look at the video I made to try to answer such questions.
Do a You Tube search on
VOLTAGE COMBINATIONS FROM ATX POWER SUPPLY
( You Tube doesn't let me paste the URL address into my reply - dang !)
You cannot use Orange plus Yellow to get 15 V.
BUT,,but . .. you can get 15 V by connecting Orange and Blue.
The Blue is negative 12 V and the Orange is positive 3.3 V , so together they make about 15 V PLEASE remember that you'll have only about 0.5 A available to charge the battery. The charging current is limited by the current available on the Blue (-12V) wire.
The nameplate on your power supply will give you the exact current available on the Blue wire.
@@disproman
Thanks!
I was drawing blanks at the time.. Iknow better!
I ended up using the voltage difference between the -12V and the +3V to get aprox. 14V and SUCCESSFULLY charged my car battery !
Hi, please let me know the use of PG wire
Can you tell me the colour of the wire
How is power on this power supply??
Witch wire use in jump please model PDP117P compaq
I do not understand the question.
The black wires are 0V , the yellow wires are plus 12V, the red wires at plus 5V
and the orange wires are plus 3.3V .
Is your question about another kind of power supply, that is not an ATX type power supply?
@@disproman dear want on the power supply.how i can on this supply supply model is PDP117P compaq
@@fkbaloch7418 I think I understand your question.. But unfortunately, I am not familiar with the power supply for the PDP 117P computer. I do not think that it is a standard configuration and that it is proprietary to Comaq.
However, you can explore the DC outputs of the power supply if you have a voltmeter and are careful to make measurements safely. It probably has output voltages in the range of 12- 24 VDC.
It would have been nice to say what all of the wires do. This seven minutes has not been explained in a methodical way.
I have a grey, purple and brown wire floating about, is this OK?
Those wires are not used when the power supply is converted to a bench power supply. They provide other voltages and control signals to the mother board. I cut them back and tape the ends to make sure they don't contact anything.
What if you don't have a green wire, I have a Dell model number PS-5201-1D power supply from a 1998 Dell. Thanks
+Don Hard
Hmmm, that's quite unusual.
All of the ATX type power supplies that I've worked on or seen , all have a green wire. It's the connection of the motherboard to "wake up" the power supply And I somehow remember that the ATX standard for the colour code is universal i.e. applies to all vendors. The Dell power supplies that I've used also have a green wire.
So, I'm kinda stuck about what to suggest.
I suppose that you could try connecting one black wire to any of the wires that are not yellow ( 12V) red (5V) , orange (3.3v), blue ( -12V) or white (-5V).
The ony thing that will happen is that the power supply will shut down if there is a fault. If that happens, simply unplug the power supply from the socket, wait 10 seconds and plug it in again ( and don't do that one again) .
+disproman Hello, Here is what I got blue, yellow, white, orange, gray, red, black, blue/white and purple.
I can send a pictures if you would like. Thanks from Don P.S. I did try black with purple and black with gray it come on for about two seconds then would shut down. any idea what to do to keep it running thanks again.
+Don Hard
I understand all of the colours you list except the blue/white.
Try connecting the blue/white to a black wire- any black wire.
+disproman Hello, Try that and it did not work. Also I did try black with purple and black with gray it came on for about two seconds then with those two but would shut down then I would unhook them and tried again and it did the same thing come on for two seconds and shut down. Also there are three blue/white wires. If you would like I can do a YouTude video and give you the CZcams address it is on so you can check it out. Thanks again from Don.
+Don Hard
OK on your testing.
Without being a smart a** about it, maybe the path of least resistance is to find another power supply - your nearest computer shop probably has a pile of them in the back. Or simply ask around who might have an old computer that you can cannibalize.
But , hmmmmm, this one is intriguing. Somehow the motherboard has to signal the power supply to turn on.
I assume that there is not other external switch on the power supply - some of them have that.
Here's the color codes
en.wikipedia.org/wiki/Power_supply_unit_%28computer%29
This source warns that some Dell power supplies between 1996 and 2000 do not use the standard color codes.
web2.murraystate.edu/andy.batts/ps/powersupply.htm
Have your taken to cover off the power supply - do a sniff test - a burnt smell or a peanut butter smell means that something has self destructed.
it could be that this power supply is defective -I've assumed it is OK, but maybe that's not right.
How can I get a 9 volt output???
Yes, you can get close to 9 V.
You can get 8.7 V by choosing the + 3.3V as your negative and the + 12 V as your positive.
It is the difference between the voltages that matters.
So, as another example, you can choose the + 5V as your positive and the +3.3 V as your negative and you'll get 1.7 V - can be used to charge a NiCad battery.
Have a look at the comment below about various voltage combinations ( you'll have to do a google search as I suggested because I cannot paste the link into the comment text box.
Can i get a bit more info on how made the current controller. must be simple, but i'm dumb. Thank you, for any help from anyone
Are you referring to the current controller in the unit with the Ammeter?
If yes, then all it is , is a variable resistor, that can handle about 0.7A. It is wire wound and I bought it at a surplus electronics store. You simply connect the variable resistor in series with the positive connection. That lets you vary the current that you allow - limited to the 0.7A. If you need more current, then you just bypass the variable resistor completely.
The current controller is simply a wire wound variable resistor in series with one of the leads - eg the plus.
thank you
should i use one yellow wire and one black wire from my computer power suppy to power my car radio
Yes, the yellow is plus 12V and the black is Ground ( or 0 V).
@@disproman okay but do i use one in the wires instead of using all bc i believe it will exceed the amps of the radio
The radio when it is playing an FM station draws milliamps. But when you are playing a CD at full blast you'll be drawing Amps. So, it depends how you are planing to use the car radio.
In any case, I usually connect ALL the yellow wires and ALL the black wires so that way I can use the ATX power supply for anything.
@@disproman are you sure its safe to connect all the wires? Like it wont blow the radio?
NOPE - it supplies 12 V regardless of how many of the yellow wires are joined together.
With more wires the 12V part of the power supply can provide more current ( Amps).
The radio will blow up if you connect it to a higher voltage .
With a 12 V connection to the radio the current will vary from milliAmps ( when it's turned on but not playing anything) to many Amps when you play the radio full blast with lots of base notes (boom boom boom) .
If you overload the power supply it simply stops working - it doesn't "blow".
You simply un plug the connection to the radio, unplug the 110V wall plug - wait 10 seconds then plus the 110V in again and you're OK to go to connect the radio
How much ampire we will get??
You can look on the name plate of the power supply and it will show how many Amps you can get for each voltage, for example the 3.3 V might provide 22 Amps.
But please understand that you will get this maximum current with no other loads on any of the other voltages.
But you can use the voltage outputs simultaneously, if you draw less that the maximum current.
In the event that you draw to much current, the power supply will shut down, but is undamaged. Simply pull the plug, and reduce the current draw and you are back i business.
i have 250W power supply. i connect black and green wire together but it didn't turns ON.when i connect and disconnect then it go ON and OFF. what i do???
What that usually means, is that there is an internal fault inside the power supply .
It is attempting to turn ON, and when it does, it sees an overload caused by an internal problem and then shuts down.
There is no easy way to fix this problem unfortunately, and the best solution is to get another power supply.
They are quite cheap ( free in most cases)
disproman its turn ON when i connect green and red instead of black(ground) wire . but its not giving proper 12,3.3,5 volts.
You can thry this:
Unplug the power supply from the wall and wait 30 seconds ( actually all you really need is 6 seconds) and make sure none of the wires are touching each other.
Then connect the Black and Green. If the fans starts turning ad then stops, it means that there is an internal problem in the power supply.
If the power supply is good then the fan will keep turning. - when the fan is turning, hte power supply is ON.
Otherwise, try another power suppluy.
disproman ok thanks. tell me one more thing is that: may i use yellow+red for more than 12 volts? means when i need 12+ volts then what i do? is it right way to joint together yellow and red wires?
No - joining the yellow and red will make the power supply stop.
Please see this video
czcams.com/video/iahc1puHUxs/video.html
It describes how the wire colours work and what voltage combinations can be obtained. from te power supply.
But please understand that the voltages over 12 V are very limited on how much current they can produce ( about 0.5A or less) .So yes, it IS possible but there are limitations. .
Waht are the purple and gray wires?
Not exactly sure, but I think they are used for LEDs and data sensing. For sure they do not have any use for supply of any of the voltages.
I found that the purple wire = "standby" and gray = "power good."
I accidentally touched green to yellow now it doesn't power up. How difficult to fix is this?
Bad news - I think you have zapped the power supply - remember that the yellow wire is 12V and the green wire is a signal logic wire that operates at much lower voltage. To repair the power supply you'd likely have to replace one of the integrated circuits.
You should be more careful in future.
@@disproman thanks
Who is this? Kumar?
does anyone know where to salvage a power resistor under 10 ohm,200watt, from old elec appliance
About the only source I know for such a resistor is a length of nichrome wire ( usually 22 Guage) that has a resistance of 1 om per ft. But dissipating 200 watts will make the thing glow red hot.
You might be able to make up a number of such nichrome wire resistors in parallel so that each one only has to handle say , not more than 30 watts.
I suspect that a resistor over 50 watts usually is fan cooled.
Come to think of it, a plug-in 1500 Watt room heater would be about about 7.5 ohms - they usually have a fan and the wiring to handle the current.
thanks,let me explain what im trying to do this might sound weird ; i made whats refered to a "nano bucket", you wrap copper wire around a 5 gl pail ,about 90 turns, you put a solution in the pail ( water vinegar salt citric acid ) apply power and put your foot inside for 30 min. The idea is to extract toxins in your leg to take the load off your kidneys. its used to heal. The power supply i used blew, it was 16v 3amp, not enough. The guy who instructed me used a power pack from a lab top which supplied 5 amps and he got results. before i attempt this again i measured the ohms of the coil pail and got .5 ohms almost a short so i want to protect the new power supply by adding some more resistance while maintaining enough power to create a sufficient field to activate solution.
Sure , it's weird, but life as we know it is weird every day.
To get 5 A from the 12 V source of the ATX power supply ( that's well withing its capability) you'd need about 2.4 ohms. The resistor would be dissipating about 50-60 watts.
So, if you could find a 12 V automotive light bulb that is about 40-50 watts ( like an old non-halogen headlight) you should be able to draw roughly 5 A from the ATX power supply. An auto junk yard is your best bet.
I would get more than one headlight and that way you could connect them in series to get less current or in parallel to get more current. Even better if you got a headlight that had low beam and high beam in one bulb, it would give you even more scope to fool around with the series / parallel connections.
BTW if you overload the ATX power supply, it simply stops. You then remove the load, unplug from the 110V wall plug, for 6 - 10 seconds, reconnect the 110V and you're back "on the air"
my new power supply is the atx , so use another load to protect the power supply other tan a resitor good idea ,i will try thankyou
hello
j'ai testé 15v court circuit pourquoi ?
I tested a short circuit 15v why?
I do not understand your question. Did you mean that you short circuited the 15V combination?
I have found that IF yu short circuit any of the outputs the power supply stops but is not dead. You simply remove the short circuit, unplug the power supply from the wall for 15 seconds , plug it back in and it starts OK.
M
+disproman
hi
when I plug the blue + orange I get 15v.
when I connect a fan or other I have a short circuit.
it works with 12v + 120v fuse , but not work 15v :(
Remember that you only get about 0.3 to 0.5A from the blue wire. I think what is happening is that you are overloading the blue -12V supply and the power supply quits.
The other voltages - 3.3V, 5V and +12V have much more power available 15 to 30 A.
If you look on the nameplate of the power supply you will see how much you can get from the -12V supply.
M
+disproman
I 12V 19A. If I understand correctly, I have not enough power, Power returned to 😵 secure mode, the only way to use the 15v source is to buy a more powerful power supply. Thank you very much for your advice.
About the only way that I know how to easily get a lot more current at 15V , is to use a microwave oven transformer, cut out the high voltage secondary winding, and rewind a new secondary with much heavier wire.
The primary on those microwave oven transformers is usually 125 turns. To get 15 V DC I would suggest 20 turns of 12 Gauge enameled wire. This will give your about 17V AC and allowing for a 1-2 V drop in a rectifier bridge, you'll get 15V DC.
The transformer can be from an old microwave oven (free) the #12 wire would be about $8 - $10 and the rectifier is about $2. That would give you at least 20 A.
sure i'm not, however mine power supply running won't
If the power supply does not turn on - you can tell because the fan will start to spin - then your power supply is not good. Get another power supply - they are cheap or free
THAT IS REALLY REALLY NICE SELL THOSE I NEED SOMETHING LIKE THAT FOR A AFX SLOT CAR TRACK FOR l.e.d.s
how come mine is reading 14 volts instead of 12 volts?
Are you measuring the voltage between the yellow wire and the black wire?
That is the 12 V connection. Check that first, before doing anything more.
@@disproman yes, sir. yellow and black wires. ok. I used two different multi tester. one is reading 14 volts the other is 13.12 volts
@@apollomorelos727
I have admit, I have never seen this on any power supply that I have made. I have made at least 35 or 40 power supplies.
So, what to check next?
Since you have quite a big difference between the 2 volt meters ( more than 5%) , it tells me that maybe the problem is with the meters. Usually the accuracy on an ordinary digital voltmeter is better than 1% error. The error on analog meters is much worse. I still use analog meters, but not when I need accurate readings.
You'll have to check the accuracy of your meters. What are the voltage readings on the other wires? eg red / black , and orange /black
@@disproman I was looking around the internet and I found this guy in a forum asking the same question why his computer power supply is putting out 14.6 volts instead of 12v
@@apollomorelos727 OK , so you watched some You Tube stuff, but did you measure the other two voltages and what were the results ? ? It could be that your power supply does not comply with the ATX specification. In any event, does your application care about having precisely 12V ?
Or can it tolerate over or under voltage?
There is nothing sacred about 12V except that you need to have it for a computer to work properly.Other applications are not nearly as sensitive.
500 mAh ! that sucks! What can you use that for? If its soaking 150 Watts to create DC volts its consumes to much energy for the little return! What's the point?
I think you mis-understand how this power supply works.
The higher voltages eg 23 V and 15V are limited by the -12V (blue) wire.
When the power supply is providing the 500mA, then it is NOT consuming 150W. At worst it consumes about 15W. It is very efficient.
There are plenty of uses for the 23V and 15V supplies - eg charging Lithium battery packs.
@@disproman Well with that kind of amperage I would have no trouble charging a car battery or even using it to crank it over then! Is that correct?
To crank a car engine, your starter will draw a peak current of over 100 Amps or about 1.200 Watts.
That's way more than the ATX power supply can provide, so, NO, you cannot crank a car engine with an ATX power supply
4:46 , where can you get a PSU FOR FREE?!?!?!
I usually go to a corner computer shop that's been there for years.
They usually have them stacked in the corner or in the basement. even if i I have to pay something, it's never more than a couple of dollars. These shops are usually run by a fellow from China making his new life in Canada servicing computers - I find it hard not to give the guy some money - just so that he stays in business.
I also get them from the electronic scrap bins uses for re-cycling electronics. I usually take the whole computer, , then take out the power supply, and return the rest to the scrap bin.
I also ask friends and contacts to give me their old computers. In return for that, I've made up the power supply for them and have also guaranteed the destruction of the hard drive.
In addition to the 3R's of a green economy, I add RE-PURPOSE -
sooo, besides for friends, where can I get it for free?
Yevette Xoxo I found ten in skip bin other day
speak up!
i want to charge my car bettery with computer power suply. But in power suply there is a yellow color wire having voltage is 12v thats ok,,, but ampere is low as about 1ampere to 2ampere only (which is not suffient to charge my car bettery). My problem is that how to increase the amperage of (yellow 12v wire) so that it charge my bettery easily.
regds,
thanks. plz reply in detail to solve my problem