Convert PC PSU into bench power supply - Page 1
Forum section: electronics / projects

author: Andryu
author_rank: Newbie
timestamp: June 09, 2025, 09:33:55 am
content: Hello, I want to convert my old PSU into a nice bench power supply.I found this video on youtubehttps://www.youtube.com/watch?v=eEs8nVUB72k,which I found really insightful so I decided to build a similar one.My goal is to have:1 banana plugfor the 3.3Volts (5 orage cables available)1 banana plugfor the 5Volts (8 red cables available)1 banana plugfor the 12Volts (7 yellow cables available)1 banana plugfor variable output split from the 12Volts (using a buck-boost converter)1 banana plugfor GND1 usb type Cfor fast charging1 LCD amp/volt meterfor the variable plugPotentiometer knobsfor the variable plug for Volts and AmpsMy PSU specs can be seen in the attached image.---After asking a lot chat GPT and contemplating how much I want to spend and how much power I should get. I decided do something I read on a comment and that is to use 2 cheap back-boost converters in parallel in order to get more of the PSU's potential at a price that makes sense.My issue is that my electronics knowledge is at a hobby level and thus I am unable to discern the BS from the truth of chat GTP.If someone with proper knowledge can please check my plan and parts bellow and let me know if there is any BS, I would appreciate it a lot.PLAN:Take 5 out of the 7 yellow wires from my PSU and connect them into a THICK wire. (PSU 12V is rated at 310W MAX)Do the same with black wires.Split the thick wires to the input of 2 identical back-boost converters (100W MAX each)Add a schottky diode (20SQ045 20A 45V) on each positive output of the convertersConnect the outputs of the converters to 2 banana plugs, 1 for GND and 1 for (+)Use 2 stereo potentiometers to replace the volt and amp pots on the converters (200kΩ each)Add a Digital Car Voltmeter Ammeter (50A 100V) + a shunt. (No idea how I'll connect it, I'll see if it has a manual when I buy it otherwise search for one on the internet)Connect 2 yellow wires + 2 black wires to a USB C decoy board for chargingConnect the rest of the black wires to a banana plug, connect the red wires to another banana plug, connect the orange wires to another banana plug.Contemplating whether I should split the 12V thick cable to 3rd cable which will directly connect to a banana plug for direct 12v and not the variable one. IDK if this splitting is too much.PARTS:Buck-Boost converter ->link5-30V to 1.25-30V 8A 100WSchottky Diode ->link20SQ045 20A 45VStereo Pots ->link200K OhmType-C decoy board ->linkRandom one I foundBanana plugs ->linkRated 30V-60V/Max 19ADigital meter ->link100V 50AShunt ->link50A 75mV 0.5ClassAny help, tips, opinion will be deeply appreciated.PS: Let me know if you need more details from me.

author: bostonman
author_rank: Super Contributor
timestamp: June 09, 2025, 11:12:17 am
content: This may not be safe.A bench power supply has current limiting. With this unit you're not protecting yourself and the circuits from excessive current.

author: nctnico
author_rank: Super Contributor
timestamp: June 09, 2025, 01:45:41 pm
content: Don't do it. There are good budget options from Korad to have a decent (linear) bench PSU. If you need lots of power, then the adjustable switching PSUs from Gophert or Rek are a good choice. You might want to replace the binding posts on any of my suggestions though.

author: nonius_
author_rank: Contributor
timestamp: June 09, 2025, 02:26:34 pm
content: QuoteHm. I've converted about a dozen AT PC-PSU's to variable voltage (2.5-28Vdc), variable current (0-10A) power supplies. Wasn't that hard. All supplies were based on the TL494 (=KA7900). The trick to add (adjustable) current-limiting to the circuit was to add a short bit of sensing wire in the transformer's ground return, and use one of the unusued comparators in the TL494. Worked a treat. If you want to know more about this method, search 'Oztules PC PSU conversion', you'll probably end up on the old forum fieldlines.comBut reading the original question of OP, I suspect this kind of modification is a bit beyond his skill-level at the moment.I've used those modificied PC PSU's for many projects: lab power supplies, capacitor-discharge spotwelder (to recharge the 1.56F capacitor bank), in a CNC-controller, etc. Some were converted to a 15-50V dc and 50-350Vdc supplies.I must admit that, on occasion, some conversions weren't entirely succesful, with bits of exploding semiconductor flying all over the place.... Anyway, it is possible to modify these PSU's to adjustable voltage and adjustable current-limiting. Would I do it again these days? Probably not....

author: SteveThackery
author_rank: Super Contributor
timestamp: June 09, 2025, 02:56:36 pm
content: You can buy adapters specifically for this purpose. Some of them are fused and have an on-off switch. I've used them - they work perfectly. I'll see if I can find a link.EDIT: here we go:https://m.banggood.com/ATX-Power-Computer-Supply-Adapter-Board-Module-24-Pin-5A-USB-Interface-for-Computer-Desktop-Electrical-Accesories-p-1983774.html

author: madires
author_rank: Super Contributor
timestamp: June 09, 2025, 03:47:31 pm
content: Did ChatGPT also tell you that an ATX PSU's ground is connected to earth/PE? And why that could be possibly a bad idea for a bench PSU?

author: Andryu
author_rank: Newbie
timestamp: June 10, 2025, 01:20:19 am
content: Quote from: bostonman on June 09, 2025, 11:12:17 amQuote from: SteveThackery on June 09, 2025, 02:56:36 pmOK, it seems to be a good idea to fuse each rail of the PSU. Chat GPT suggested 25A car fuse for the 12V rail, 20A car fuse for the 5V rail and 30A car fuse for the 3.3V rail. Will this be okay or do you guys recommend something different?Quote from: nctnico on June 09, 2025, 01:45:41 pmI am mostly doing this for learning and to feel good since I always wanted to convert a PC PSU. Realisticly I probably don't need a bench PSU. My use cases are somewhat limited as I mention further bellow. Also thank you for the recommendations I will keep them in mind for the futureQuote from: nonius_ on June 09, 2025, 02:26:34 pmQuote from: madires on June 09, 2025, 03:47:31 pmYou guys gave me a headache xD. I think messing with the PSU circuitry is way above my skill level and probably overkill for this project hence the use of cheap back-boost converter. Also isolating the GND is too expensive or hard for me and probably overkill as well for this project. IK chat gpt is bad which is why I posted here but it's convenient AF for noobs.I plan to use this PSU only on household devices (cheap battery devices) like toys, cheap DC RC motors, laser pointers, cheap flash lights etc.Thanks to you guys I've added some rules for using it:1. don't use it with more than 1 device at a time2. don't use it with expensive devices3. use the USB TYPE C to charge only smartphones and tablets4. be careful not to ground a device connected to the PSU. I should place it on non-conductive surfaces and touch it only if I am 100% not grounded.I also plan to power breadboards with simple circuits and maybe more complex ones in the future, is this use case ok or should I use batteries instead?---I understand that it will have a high risk of frying a device, that it is not meant for a PC PSU, but is there also a high risk of frying the PSU itself even with the added car fuses? Is there anything else I can easily or cheaply do for added safety or even rules to follow?As I understand my plan should work but with a big asterisk on safety, correct?---Thank very much for your knowledge guys and enlightening my noob *ssPS Sorry if I misunderstood anything as my elctronics knowledge and understanding is very poor

author: bostonman
author_rank: Super Contributor
timestamp: June 10, 2025, 02:08:38 am
content: If you're new to electronics and want to experiment, don't tinker with such lethal power.

author: Smokey
author_rank: Super Contributor
timestamp: June 10, 2025, 02:21:29 am
content: Quote from: nonius_ on June 09, 2025, 02:26:34 pmwhat enclosure/rack is that?

author: BadeBhaiya
author_rank: Regular Contributor
timestamp: June 10, 2025, 06:30:11 am
content: I say go for it. Its a fun educational project and you get usable equipment out of it. ATX power supplies are cheap and relatively safe. Just make sure its earthed properly and you're good to go.I too have wanted to build something similar but for the time being, I just use 18650 cells to make whatever voltage I need

author: UnijunctionTransistor
author_rank: Frequent Contributor
timestamp: June 10, 2025, 12:02:24 pm
content: My recommendation?Put more than a single banana plug for the ground connection.If you plan to draw several amps from one of the high current outputs, an Anderson powerpole connector would be useful.

author: bostonman
author_rank: Super Contributor
timestamp: June 10, 2025, 12:34:55 pm
content: I'm still uncertain why the support to work with such lethal currents for someone new to electronics.The voltage is low, but you have lethal high current potentials along with a mix of positive and negative voltages.Too many wires which may cause confusion. Next minute something is wired wrong or something is touched by accident, and the person will get a bad shock.

author: madires
author_rank: Super Contributor
timestamp: June 10, 2025, 01:29:20 pm
content: Quote from: Andryu on June 10, 2025, 01:20:19 amNope, it just means that any DUT's ground is connected to earth/PE via the ATX PSU. It doesn't make the DUT dangerous.(DUT: Device Under Test)

author: bostonman
author_rank: Super Contributor
timestamp: June 10, 2025, 01:37:37 pm
content: My point was simply: the more wires, the more potential to connect something wrong.It's just my advice that if the OP is starting in electronics, start with simple stuff until the basics are learned; then move up to larger stuff.

author: Andryu
author_rank: Newbie
timestamp: June 10, 2025, 01:43:16 pm
content: Quote from: bostonman on June 10, 2025, 12:34:55 pmI am not new to electronics. I can test and replace every component on a PSU safely without issues, thankfully my 2 brain cells can do that. My issue is that my knowledge in electronics theory and physics is so basic that's not even worth mentioning but not non existent. I have enough confidence to safely do this project and that's also the reason I don't want to mess with the ATX PSU circuit itself but only with the output of it. Also I didn't straight out jump on the project, I watched youtube videos, googled around and asked for advice on discord and on this forum which fortunately got me plenty valuable knowledge to make this project better and safer.

author: blackdog
author_rank: Frequent Contributor
timestamp: June 10, 2025, 01:50:13 pm
content: Hi Smokey,The case is olmost for shure from the brand Schroff from Germany.https://www.nvent.com/nl-nl/schroff/products/desktop-casesKind regards,Bram

author: bostonman
author_rank: Super Contributor
timestamp: June 10, 2025, 02:03:10 pm
content: QuoteMy opinion was an opinion based on being safe.You can learn electronics, especially power supplies, much easier and safer. You're basically trying to learn about electricity by climbing up a telephone pole to check how it's wired.

author: Andryu
author_rank: Newbie
timestamp: June 10, 2025, 08:37:31 pm
content: Quote from: bostonman on June 10, 2025, 02:03:10 pmI heard you the first time and thanked you for it. At this point it's becoming annoying, please move on and let me climb my telephone pole in peace.

author: bostonman
author_rank: Super Contributor
timestamp: June 10, 2025, 09:56:10 pm
content: QuoteSeeing as how you only have four posts, I assume you're unfamiliar with this forum implying you're new here.People on here take extensive personal time to answer questions for complete strangers. It's something I appreciate, and, unfortunately, find myself more often than not unable to answer a question due to not knowing the answer; or it's already been answered. If anything, I want to contribute more to this forum because of al the generous contributors on here (and I'll give a shout out to Lemon64 too).Your comment was uncalled for. I took the time to place emphasis on the safety aspect of your project and you respond with an ignorant reply. You seemed adamant to take on a task that I, along with a few others (nctnico was one of them), suggested not to do.Maybe as you use this forum a bit longer, you too will have respect for the time others take to provide answers and realize you got sarcastic with a person who took the time to show concern for your safety.I've read threads where people want to float their scope and numerous users on here repeat over and over the safety issues. I was following suit by placing emphasis on the safety aspect of it and making sure I was in no way part of contributing to the possibility of you injuring yourself.QuoteBy all means, climb the telephone pole and touch the wires because you watched YouTube videos and know how to be safe. If you can, please post an image of the Engineering degree you earned from YouTube University because I'm sure it's worth more than those (including myself) who earned Engineering degrees from accredited colleges/universities; or have extensive experience (which I've found in my years to sometimes be more valuable than a degree).

author: SteveThackery
author_rank: Super Contributor
timestamp: June 11, 2025, 10:13:32 am
content: Quote from: madires on June 09, 2025, 03:47:31 pmChatGPT? Don't know what you are on about. I went to Banggood, because I've bought the linked item before. Good point about the earth connection, though - thanks for pointing it out.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: June 11, 2025, 12:27:49 pm
content: Oh my, this guy is crossing the wires (07:40) He clearly has not seen GhostbustersAlso, you can buy littleconverter PCB's on Ali / Eaby / China direct with an AT power supply connector, fuses and screw (or other) terminals. There are different models available.

author: madires
author_rank: Super Contributor
timestamp: June 11, 2025, 12:50:59 pm
content: Quote from: SteveThackery on June 11, 2025, 10:13:32 amSorry, my comment was meant for the OP. But I'm glad I could help.

author: SteveThackery
author_rank: Super Contributor
timestamp: June 11, 2025, 06:58:38 pm
content: Quote from: Doctorandus_P on June 11, 2025, 12:27:49 pmTry reading the thread. I linked to one way back in post 4. And there's a picture!

author: marco58
author_rank: Newbie
timestamp: June 12, 2025, 10:01:46 am
content: Dear OP,I don't want to be rude, but I cannot avoid some considerations.As some others members already said, perhaps you do not have necessary skills, now.Please trust more our help (and not GPT or youtube) and study some basic theory.If you need asking GPT about fuse choice, when you do have nominal values of your PSU, I must think you do not know (or are too lazy to think yourself) how current and power relates.Your PSU value mention voltage, current and total power (I suggest take these values with a grain of salt: these are intended for PC load and are referered to instantaneuos peak load, I presume. If not plain "advertisment data") so you have all needed information.I hope you know how fuse are generally specified. Nominal current is the current that can be sustained indefinetily without burning. Burning current is much higher and can be also twice the nominal and intervention time is also somewhat long.Fuses are ok to protect wiring cables, but electronic stuff is another story.I don't know if car fuses are different, but use GPT to find a real datasheet and check current and time intervention.You think to use 2 buck-boost converter in parallel, I suppose with schottky diodes and stereo pot.I think this is not a good idea.Stereo pot tracking between sections is poor and a so voltage outputs do not match well (and also resistance / voltage ratio may differ from unit to unit due to other components tolerances).Also schottky diodes have tolerances.So a little voltage difference may cause one only converter to supply all requested current until it overloads and I don't how a 5 euros converter may react to misuse.Generally speaking power supplies can be paralled only if stated by constructor and with the specified info.Hope this helpciaomarco

author: MariuszD
author_rank: Regular Contributor
timestamp: June 12, 2025, 11:30:33 am
content: Quote from: bostonman on June 10, 2025, 12:34:55 pmLooks like you don't know what is the difference between potentials and currents. There is no such thing as "lethal high current potentials" There is no chance of being electrocuted by 24V.By scaring with a non-existent threat, you divert attention from important issues.A power supply with high current and low voltage (3.3V 30A) can melt a long thin wire (eg AWG 24) if a short circuit occurs.The power supply has internal protection. The fuses at the output are meant to protect the wires and connectors (eg USB), not the power supply. The thin wire will melt before the protection in the power supply activates.QuoteA linear power supply with adjustable voltage and current limiting is the best for this purpose. If your circuit has errors but you connect it to a power supply with the limit set correctly, the power supply will protect your circuit.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: June 12, 2025, 12:56:03 pm
content: Quote from: SteveThackery on June 11, 2025, 06:58:38 pmI should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.I should read posts better and with more attention before I place an unthoughtful followup.Gosh, doing that 100x on the PC is much quicker then on paper.

author: bostonman
author_rank: Super Contributor
timestamp: June 12, 2025, 01:35:36 pm
content: QuoteWet your hands and touch 24V wires that are on a power supply able to supply high current. I don't know what will happen, but do you really want to find out? Personally I think you'll get a good shock, maybe stick to it. Or open your car hood, wet your fingers, touch metal, and touch the positive of the battery with the other hand.If you do it and we don't see an update from you, well, guess we got our answer.If I remember, from safety training at an old job, 24V DC - 26V DC was considered the maximum allowed to work alone in a room. Any more and we were to have someone present in case of an accident.

author: MariuszD
author_rank: Regular Contributor
timestamp: June 12, 2025, 04:44:52 pm
content: Quote from: bostonman on June 12, 2025, 01:35:36 pmI tried with 30V and wet hands. I don't feel anything. I knew what the result of this experiment would be before I did it. Electricity is not as scary as you think. 30VDC is considered safe even in wet conditions.Quote from: bostonman on June 12, 2025, 01:35:36 pmYou've watched too many movies.Quote from: bostonman on June 12, 2025, 01:35:36 pmGoogle for safe voltage you will find 120VDC.https://en.wikipedia.org/wiki/Extra-low_voltage

author: bostonman
author_rank: Super Contributor
timestamp: June 13, 2025, 02:11:58 am
content: Then why touching a 9-volt battery to your tongue result in a shock?It's only 9V DC and the tongue is moist; same conditions as wetting your hands. I would have expected 30V to give you a jolt.

author: MariuszD
author_rank: Regular Contributor
timestamp: June 13, 2025, 08:50:56 am
content: Quote from: bostonman on June 13, 2025, 02:11:58 amNot the same. You have skin on your fingers but not on your tongue. Stratum corneum is a good insulator at low voltages.When warning OP about danger, write only what you know, not what you expect.

author: bostonman
author_rank: Super Contributor
timestamp: June 13, 2025, 11:57:11 am
content: QuoteAccidents occur because people are careless and think they know. You're working with electricity, nothing should be overlooked.Current kills.Just because the 30V didn't break the insulation on your skin doesn't mean it can't happen in the right conditions.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: June 13, 2025, 11:01:45 pm
content: Some 30 years ago my brother was welding (AC MMA) in a not so easy accessible area. On a hot summer day sweaty bare chest and lying on his back on a stack of (grounded) steel tubes he accidentally dropped the welding torch on his chest. Later he told it was very unpleasent, but he did survie obviously.

author: MariuszD
author_rank: Regular Contributor
timestamp: June 14, 2025, 07:33:23 am
content: Quote from: bostonman on June 13, 2025, 11:57:11 amYou can't be cautious all the time and watch out for everything. Such an overload of information will cause you to miss something important. You yourself gave an example of this; you are writing about an electrocution that won't happen, diverting attention from the risk of a fire.Google for "molex to sata fire" In low voltage high resistance circuit over-current protection will not work. Fire sustained by an electric arc can burn for long timeAll my accidents occurred when I was very tired. I knew what the risk was, but I had to finish the work, and at some point, I did something I would never do consciously. I'm not just talking about accidents with 230V voltage, but also with sharp tools. After day of hard work and sleepless night, a kitchen knife becomes dangerous.Quote from: bostonman on June 13, 2025, 11:57:11 amIt can't happen at 30V. It can happen with 230V. It will happen at 1000V.

author: bostonman
author_rank: Super Contributor
timestamp: June 14, 2025, 01:36:26 pm
content: How about a very wet car battery. I know it’s not 100v and only 12v, but still. You get stuck to that and you’re in trouble.

author: bostonman
author_rank: Super Contributor
timestamp: June 15, 2025, 02:59:25 pm
content: QuoteAfter some reading, yes, I'm finding DC voltages to be much higher than I thought, but also, I found the above. It goes on to state that if a person has a cut or the probes go into the skin, then it can be lethal. Also, I didn't find anything about the skin being any different than the skin on the tongue except it's (obviously) much more moist than dry skin on the hand providing less resistance.To elaborate on my point in all this. I wasn't necessarily suggesting working with the power supply can kill. In a roundabout way, I was suggesting that if the OP wants to learn more about power supplies, building a simple linear one may provide more knowledge than working with something that has high current capabilities. If the OP needs 5V and 12V for a project, then it makes perfect sense. If trying to learn about electronics, much simpler and safer methods exist.