Simple Cheap High Current Power Supply From A Microwave Oven Transformer
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- Опубліковано 21 жов 2024
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My bad in the vid I said take a turn out - I meant put a turn in - more turns higher volts lower amps - less turns lower volts higher amps - sorry
OK, I found and subscribed to your channel because I saw one of your video thumbnails, and actually thought you were my estranged uncle, I've heard of twins, separated at birth, but I'm saying he's got a out 6 yrs on you,but for the un aware,you guys could really pass as the same! VERY funny, we are from alexandria N.H. he's not familiar with youtube,UA-cam, I showed him! He's a engineer genius, can't move around much in his house because of all the Bridgeports/ lathes/ importants that have been retained for projects. I admire what you do and have learned so much from you. This funny twist has brought my uncle and I much closer, and I'm learning from him also. Thanks for all you do.( he was even wearing one of his many favorite blue collar shirts( light blue,of course) when he saw your video,he doesn't wear much else) hilarious!
When I worked on TVs about 20years ago I had a set come in with a weak crt those old boosters we used on old tube sets wouldn't work on a solid state TV because in a SS tv the filament voltage comes off of a winding on the flyback trans which made it a high freq. voltage I think it was 15750 khz. One day I was looking at the schematic of a RCA set and thought why couldn't I add a few windings on the fly back to increase the filament voltage. I found out 1 turn of wire around the core was about 1volt I usually used some 20gauge telephone wire! That worked perfect 3turns in series with the original filament winding gave about 8 volts on the filament of the crt and a lot brighter picture. Never had one come back. Oh yeah you had make sure when you connected the new winding in series with the filament voltage that you had the polarity correct. Fun memories!
I have a whole stack of the MOTS stashed away, it is very inspirational to see this.
now I am jealous lol
This is that kind of experiment every tinkerer must do at least once in his lifetime. Thumbs Up mate.
lol - for sure mate
Very cool. Now if only dead microwaves were more commonly in the rubbish around where I was.
For anyone wanting to build one of these, you have 2 things to watch out for when it comes to your output voltage:
1 - With those bridge rectifiers you end up with 2 inline diodes at your output, so subtract a volt or so (0,6 - 0,7V per diode). That's not that problematic at 12V, but could be if you wanted to make a low voltage for a single cell device.
2 - When you measure the voltage output from your bridge rectifier, it's an averaged voltage (RMS incidentally). Being rectified AC, the waveform is choppy, with peaks at 16,9V for a 12V AC waveform (multiply the RMS value by 1,414 [the square root of 2])
Hopefully I'm not taking anything away from a future video here, Rob.
lol - no it's good mate - I am glad you posted the help - it's part of what I like about the channel - how much folks help
Absolute inspiration. I liked your suggestion to set up the 240V side first with full insulation, etc. then I thought, to enclose the 240V side that will also act as mounting for the transformer. The other thing you may want to do is to make 2 x 6V windings that you can then configure to 6V at (higher current) or 12V and with the option of using it as a centre tapped to reduce the number of rectifiers in the 12V configuration.
I like that mate - I went for utter simplicity but a centre tap pig tail would be super simple too and give options - nice one - cheers
Awesome again, the money saving science expert 👍 put an extra turn in to increase the voltage as Robert states in his full scroll down description 😉
thank you for bothering to read that mate - I have had several comments already for that slip of the tongue - it was late and I din't fancy redoing that part of the vid so I put it in there - most folks - of course - haven't read it lol
Spectacular. Truly. I've watched so many builds for a dc power supply and yours is fantastic. Your videos helps me more that any other on the internet. Thank you
Really interesting project giving someone's junk a new life. I look forward to seeing it in use in the next project.
Thank you for taking things apart and recycled materials reused to make an invention like a sherlock homes and MacGyver...
Appreciate your efforts in explaining what and how. Really cool
Thank you for posting this 'electrifying ' video, it was very inspiring and has me motivated to build 1 myself and get all charged up in the process 🙂
Back when I was a teen, a long, long time ago, CB radio was all the rage. I built a 12v power supply by re-winding an old tube power supply with heavier gauge wire for high current low voltage. It worked great although was a tad low. Should have put another turn or tow on it. I'm going to keep an eye at my recycling center for old microwaves in the future.
awsome mate - cheers for the post
I did one of these for a project and it’s nice to have a very robust 12v supply at my bench. I did include a little smoothing on the output with an electrolytic capacitor. I also did a similar one with an adjustable momentary circuit to spot weld nickel tabs on 18650 cells. I keep a spare transformer in case I need to work up a different voltage. I was thinking of a secondary winding with two or three tap outs on the next one. You can get high amperage rectifiers easily on eBay.
awesome mate - thanks for sharing
Entertaining and informative; love his cheerful demeanor.
It's a joy to see this enthusiasm.
After so much I've seen and heard about rewinding MOTs, this must be the most refreshing thing you can get as a demo, so I can only praise your relaxed way of making the real facts available to everyone and ending it for good with the usual ghosts about transformers, of whatever type.
Congratulations.
Greetings from Portugal.
cheers mate - thanks for taking the time to post
I'm sure you know this, but for anyone who doesn't, once you rectify that 12v AC, you'll end up with about 17 volts DC, because AC is measured on the mean (RMS) - not the peak like DC.
To determine what your final DC voltage will be, you need to divide your new transformer output by .707, so 12 ÷ .707 = 16.97 volts.
It may not matter in your particular setup, but for someone expecting 12 VDC, they might be puzzled... 😁👍
Ture talk no lies long time i anit hear bout peak to peak...now on his project we could use a 12volts voltage regulator an a 2n3055 n get that 12volts more stable...more electronic to add to better the power supply
You remind me of an uncle I have. lol I learned so much stuff from him when I was growing up. yeah !
cheers mate
Telecom here in the US uses -48 volts to power everything. You can get a little bit of a tingle from that on occasion. Especially if you are a wee bit nervous and sweating up a storm. You do have to be a little careful because of the 10,000 amp battery backup.
And then there is the ring voltage which can give you a bit more of a "tingle"... :)
I am going to have to build a playlist just on microwave transformer uses.
I love all of these projects. What's great is you may have most everything you need lying around. If not one of your neighbors probably put one out by the road.
I should do that too - the uses of MOT's just grew lol
Excelsior! Outstanding mate! Enjoy every video and you are an inspiration to me and the world!
Wow, thank you mate
@@ThinkingandTinkering what kind of bridge rectifier do i need to use to make a 24v power supply
I just love the logic you posses Sir. Reusing a microwave transformer is just the best bang for the buck ever invented for sure. I have made a few and am confused when people ask me of how I made a power supply or how much it costs. Keep up the great work and am looking forward to your finished products. Good day and peace too Robert. VF
for sure mate and cheers
@@ThinkingandTinkering Keep on making great videos Robert for us all to enjoy online. Stay virus free also.
The 12Vac RMS when full wave rectifed will give you 0.90 X 12 V rms = 10.8 V D.C. average minus the full wave diode drops of about 1.0 volt each at high current ( two diodes conduct on alternate halfs cycles). So you get a full wave rectified or dirty D.C. output of 8.8 Volts average. The peak voltage of that full wave rectified or dirty D.C. will be 12 x 1.41 minus two diodes drops ( 1.0 V each at load) or about 15.0V. If connected to a 12V lead acid battery, the battery will act as a filter to smooth the dirty d.c. I suggest if you do connect to a lead acid battery you put a a 55w 12V halogen globe in series as a current limiter. They are very low resistance at low voltage across them but limit current should your load short circuit.
Barry Moore excellent advice!
nice one mate - thank you
@@ThinkingandTinkering halogen globes can be put in parallel for more current too. It's cheap insurance against a fire from a short circuit. It's not a new idea to use a globe as a current limiter. My Hornby train transformer in my childhood had one behind a red plastic cover. When the toy train derailed and shorted across the rails it glowed bright red. Loved those days ... lots of derailments.
Can we see a proof of concept test with the Chain mail and pool of salty water please? Go on...you know you want to! :o) xx
lol - you are right - I am tempted lol
Full chain mail would be Faraday cage
Hi Robert,
Just subscribed. The bit about holding the positive and negative on a 12V supply was my primary takeaway. I’ve recently moved aboard a 34’ yacht and I’m trying to get to grips with the 12V supply internally. Living in a 12V world seems very different. (I’m a biologist so electricity terrifies me 😂😂😂).
thanks for the sub mate - and good luck with your yacht - i'm just a tad jealous
Robert Murray-Smith I’m moving from Belfast to Cornwall so you’re welcome to pop down and laugh at my wiring! 😂
And drink my booze stash!
Loved your video. You are very charismatic! Love the way you present things. Thanks for sharing.
Glad you enjoyed it!
Just received my variac today now I have a project other than my heating mantle.
Thank You sir!
cool mate - cheers
I rewound a microwave oven transformer a few years ago. I have yet to get more parts I need...and design. I made mine for a high current 6 and 12 volt battery charger; made two secondary coils using proper transformer wire gauge 10. Got some wire from a shop that rebuilds electric motors. I don't recall exactly what the final voltages were but should be at least 7 and 14 volts, for losses and to push power into batteries when near fully charged.
I still have not decided or found a very simple high current capable circuit design, but I want to be able to control the current, limit it. I want to have full manual control to handle all types and conditions and situations and sizes of 6 and 12 volt batteries. I need to be able to monitor both the voltage and current. I plan to fuse the DC side at max 30 amp. The transformer is able to handle more, but I do not need more when I can limit the current.
For two examples: 1/ Charging a very large heavy equipment battery that is low, can pull a lot of current, which is why they make very large battery chargers for this. A 30 amp charger can do the job by limiting the current and charging more slowly; increasing the current bit by bit to keep the charge voltage about 1 volt above the batteries voltage.
2/ Attempting to restore a badly scaled and shorting battery, by trickle charging, by limiting the current, and very gradually increasing the current as the sulfur scaling dissolves....hopefully.
"Smart" chargers can't handle all situations. I want a fully capable charger, and me be the smart part....hopefully ;-)
I have been looking at some pre made circuits people are using but they are low current and look flimsy. I have been achieving current limiting control with store bought basic transformer battery chargers, by adding inline various automotive light bulbs.
I will order a high current bridge rectifier ASAP, and get this project back on my work bench...schedule lol
A decent charger IMO, also needs to cut off when the battery is charged, when the smart part, gets distracted. A timer could work as well.
101 projects needing to be done, can't do them all, what to choose, what to let go for now?
You continue to impress mate! Thank you, these are amazingly useful. Much appreciated!! 👍
LO,
MY RETIREMENT HOBBY IS WORKING WITH TRANSFORMERS, AND WASHING MACHINE MOTORS.
YOUR TEACHING method is top notch.
I NEED A LITTLE MORE DETAIL ON PARTS SO THAT I CAN PURCHASE PARTS SAFELY.
TO MAKE A BRIDGE RECTIFIER, I NEED TO KNOW, IS THERE A PARTICULAR DIODE AND WHAT DO I SOLDER THEM TO.
PLEASE HELP.
REGARDS
PETER.
What can I run from this power pack?.
Regards
PETER
Another good place for massive transformers are old fashioned UPS boxes (uninterruptible power supplies - for computers/servers). Lots of them get thrown away by IT departments. Easy to snag them, and disassemble. Sometimes the only thing wrong is a bad battery, but the replacement is more expensive / time consuming than a new one - which is also more efficient.
good pointer mate - thanks for that
dang.. it seems like when I get an idea of doing something and come to a thinking point you always seem to hit the nail on the head.. I needed a 12 volt dc power supply with 30 amps.. I was just starting to think of a way to do it and boom! "there ya go" I just love love the road less traveled.. so many things lay there unrealized there.. I just wish the haters could realize what you are doing.. they could be so much more complete as a whole if they had some adventurous spirit to them to see what you are doing here... As always Rob.. thanks again... carry on!
Or use an atx computer power supply with 30a on the 12V rail. It is regulated and you get it dead cheap.
@@JonnyDeRico Yup jonas that is a good one also.. but I have tried that I actually made my first bench power supply out of one.. but they have to work to hard for 30 amps and I am trying to keep the heat down a bit.. But thanks for the idea.. it is a good one for sure... I still have the old bench supply mod.. I use it for running my cb base unit and charging my cell phone..
Unless its about fiddling around with a MOT, an ATX-supply from the junk bin is the sensible solution, like jonas pointed out. If need be, you can get rather beefy server-power-supplies (> 1kW) extremely cheap on ebay.
tinkmarshino: use a car battery, voltage is a bit higher but doesn’t need a rectifier and piece of wood. Still need thick wires but if you have jumper cables you’re good to go. Will need to charge it of course.
Cheers mate - and folks are dead right - you can get power supplies from all kinds of places - from buying one to reusing other equipment and even just a battery - but as you see - that's not the point lol
The size of wire you used, in USA, would that be equal to 12 or 10 gauge wire ??? The way you described the wire seem to be what we call Romex. Used in house wiring. It has a bare copper ground and one wire coating in white and one coating in black and all 3 are jacketed in a plastic sheath. If this is what you used, did you leave the fiberglass inserts in the transformer core? And did you just loop the wire or did you bend 90 degree turns.?
a rectifier used in a car alternator would work too, ideal for high current low voltage
Riding mower engines as well and they are easy to get off
You have given me a new love of all things electrical, love all your videos
cheers mate
Great guy - I love the way he explains ... thanks dude!
I would use a pc power supply myself. The 12 v rail always is about 20 amps., I believe. More amps in psu's from the 90s. I have a few of these big trafos myself. I try to steer clear from mains even though I know with a few precautions you are safe. But it is damn interesting making your own hydrogen!
for sure mate - and nice advice - cheers
Hi Robert, and thanks for the informative video. My only concern is the chuck key sticking out of the lathe chuck behind you. Just as dangerous as electricity if not removed before applying power... 😐
Nice to see practical advice in action. And I caught the "memo" that you meant ADD a turn to the secondary. You had me going there.
Now my own project issue is I have a nice 6A transformer with 110VAC > 40-0-40 secondary. Following that is a 10A bridge rectifier so it's wired full wave. So far, so good; it reads 40VDC on the two rails, compared to the center tap. But when I add in some smoothing capacitors - 4700 uf, the DC reads 60V. Too high for me by 5 to 10 Volts, because of the 55VDC input spec. limit of the adjustable buck converter it's meant to supply.
What's a suitable way to cut down 5 to 10 volts and still have a supply of 50 volts up to 5 Amps for my project? Power Resistor? String of 10A diodes that I have plenty of?
Very simple and very good explained. As you said: Don't be afrait of 12 Volts; 240 Volts is a differnt story. BUT: Be careful with high amps vs. diameter of wires! They may become hot if they are too small. I made my donkee bridge to say: Roughly 10 amps per square millimeter - than you are on save side. So with 50 amps 6 mm sqare is ok.
But you can take (I think) an ordinary cable 3 x 1,5 mm2 and run the single wires parallel. You have than 4,5 mm2 - just enough to take 50 amps. (A little bit over the above "donkee bridge, but for short cable up to 4 m should be ok)
for sure mate - you must check the ratings - but that is all over the net and the do change for installation method but in free air the rating for 4-6mm cya should be fine for this amp draw
@@ThinkingandTinkering Just to nitpick, is wire stuffed into a transformer and then enclosed in a shielded box actually free air? I would expect some derating in that use case.
Super excellent idea great use of recycling and great power supply that is one of my next upgrades thanks
glad you like it - cheers
Watch all thrown out busted microwaves disappear. Ironically the one thing that can't really go wrong is the big transformer lump.Great video again.supurb
cheers mate
If people do not have an MOT, or are nervous of messing with mains electricity, you could use a 12V car battery for the electrolysis experiment.
Make sure you include a suitable fuse in circuit :-)
Indeed - a diesel car battery is particularly good, ^oo^
nice one mate
This guy is amazing, like really amazing. Thank you so much for doing all these videos.
Nice video! Dry skin has megohm resistance but the electrolytes inside are highly conductive. Cuts in hand could put 100 mA across the heart from a 12vdc source and put the heart into fibrillation. Better to err on the side of caution.
you are right mate - you really should avoid standing in a bathtub dressed in chainmail if working with this - I joke obviously - thanks for the tip mate
server power supplies can be had cheaply 12 volts at anywhere between approximately 40 to 120 amps
Another relatively cheap source for high current power supplies are second hand server power supplies, it takes some legwork to find a reasonable source, but they can be really nice. I have one that can deliver 12V 53A with no problems at all... the hardest thing is doing some googling to figure out how to turn the supply on outside the server chassis, and to be honest it won't take you too long to find that info
awesome advice mate - cheers
As long as I dont dress myself in chain mail and stand in a pool of salty water. LOL! Your presenting skills are awesome mate. Just awesome!
lol - cheers mate lol
Nice project - the MOT will draw maybe 5A of magnetising current and over 100W of power even with no secondary load, so take care it might get hot, especially if you put it in a box. Its because 1 volt per turn is too much for a small area core like this, it is done to save money on manufacturing the ovens.
You didn't say or show but, what did you take out, the primary or secondary wire to replace it with your own? It looks like you took out the secondary?
Alternative , to find high current transformer ...
In computer ups .
In inverter.
Computer ATX ( as complete supply )
ATX supply will work great. Keep in mind if powering any circuit involving RF or high speed switching you'l need to put a filter on the output to protect the supply from back emf.
Fantastic video and a great explanation , , Question though Could you charge a car battery with that and how many watts does it put out , , roughly how long would it take ,also what would you use it to power out of interest and thanks in advance
Good day Robert. love your vids, and don't miss any of them. Have a request. Can you please do a vid on using a Micro Oven Transformer for a House generator. Or perhaps tell me what else I need, apart from the Transformer, to do the Generator. Many Thanks. Wayne. Alberton. Johannesburg. South Africa.
Just aquired a transformer for a spot welder project.Question. can I use carbon rods from a lantern battery as the weld probes if not what's best material? As ever great instruction videos.Thanks
i wanted to build a supply like that but for non-series confiurations (more amps, less voltage) but at that point the voltage drop from the rectifiers gets horendously inefficient (the beefy ones are usually also for high voltage, thus diodes in series). you should revisit this but make some kind of active rectifier circuit using mosfets or something. (for like 8 volt 200 amp molten salt electrolysis) for now i'll stick to chineese led power supplies.
Sorry if this has been answered, but for these results, is 10awg wire about the same size? And about how many feet. Also looking for 12 volts. Thanks for the information, love these projects. Any recommendations for some cheap gloves with a bit of protection also. Thanks!
This is fantastic! I tried get some rust out of my VW T25 fuel tank using electrolysis but it's a very large item and takes 60L of my electrolyte mix. I used a 12 volt 2amp power supply but that's not cutting it. I walked around the corner and found a discarded microwave on the street. Quick question: there are aluminium blocks between the primary and secondary coils. Do I put those blocks back in when I rewind the secondary coil?
Over here in the US we call that big gray wire 10 - 2 with a ground!
true enough mate - cheers
It would be interesting to hook up an o'scope to that to see how clean of a 12VDC was generated...
For anyone who would prefer avoiding the mains wiring side of this, might I suggest a 2nd hand server power supply as an alternative. As I type this, a HP 506822-101 750 watt, 12v 62.5a power supply would cost about £8.50 shipped from ebay - probably less than the cost of a decent rectifier bridge if bought new.
true enough - some people would rather recycle things though mate
Your videos are delightful.
@Robert Murray-Smith I wonder if something like tis would work to recharge my battery bank for my solar system. It's a 12v system wit around 10 deep cycle batteries? I find that I need round 80 amps to have any kind of charge for the size of the bank we have. Do you think this would work?
I’m going make a Brown’s gas go cart. Which will simultaneously grill a pop tart.
If you want an alternative cheap 12v DC power supply check eBay for refurbished or 2nd hand HP server power supplies. They can handle from 35 Amps to over 100 Amps for between 8 - 20 GBP which might even cost less than one high current rectifier bridge if you have to buy one.
Oh apparently first comment too!
awesome mate - thanks for that
@@ThinkingandTinkeringYou need to short a couple jumpers to switch it on - info on YT shows how or hit me up if you need help!
I think you will find, a 1.2v battery has the potential to be lethal (cause cardiac arrest) if you bypass the resistance of your skin, which breaks down at different voltages allowing current to flow, this will also depend on the type of skin you have and where the current flows. Never touch battery terminals if you have cuts on your fingers, or if you are stupid enough to have fresh piercings on your fingers.
Hey Rob Sir, great power supply gives an answer to my question, lovely informative video, Yes some people are scared of 12V coz they get a heart attack if at all they hear the Whizz n buzzing sound of electricity 😅😅😂😂😂😂😂🌹🌹🌹🌹
There is a lot of aluminum clad 10guage cheaper wire on Ebay, are there any complications with using this wire as opposed to the copper? I am trying to make a 12volt to 120 volt inverter. I am having difficulty finding any solid answers by doing a search. Thanks.
Loving the English approach rather than the ott American channels. Newcastle upon Tyne here
lol - we are more reserved lol
Robert Murray-Smith not sure about reserved more a genuine person and not some fake wannabe
I have a 1,350 watt microwave that I will be scrapping .... at 120 volts feeding in , I will safely have 11.25 amps available at the primary side ....... I have 10 gauge solid 2.7 mm thick copper .....I want about 25 to 35 amps to run 200 watt ham radios....So this is a great way to have a power supply on the cheap... I will do 3 turns to see what it puts out , then I can do the math
I heard you say that you wanted 12 volts , but ended up with 11 volts , taking a turn off will drop you to about 10 volts , then you minus 2.5 volts for the voltage loss that the bridge rectifier will steal and you will end up with 7.5 volts ...... You might have had 13 volts but said 11 volts ??
Oopsie , I just read your description box for the slip of the tongue ....... I will leave the comment as is though , because it has some possibly worthy words in it ..... Thanks Boo........
Could you start a car with this like a jump starter if you had thicker wires from it?
U are very knowledgeable sir! I enjoy your videos quite a lot!
thank you mate and thanks for taking the time to say so
FYI... You should be careful with having an extension cord on a spool like that. It doesn't allow the heat the dissipate. A few years ago, I was at this fundraising carnival for some organization and one of the booths had a large popcorn making machine. Since there was no power outlet within reach of the power cord that was on the machine, he had a long extension cord on a spool and only unrolled enough of it to reach the nearest outlet. That left quite a bit of cord still on the spool. It didn't take too long after he started up the popcorn machine for the cord the get warm enough for the plastic insulation to melt and the wires to short together resulting in a large mass of plastic and wires fused together after it cooled off. I don't know what the wattage of that machine was though -- probably at least 1500W. Since we use 110V here instead of the 220V you use, the amperage would have been twice for the same wattage. Still, its something people should be aware of -- unless they LIKE the smell of melting plastic insulation... :)
thanks for taking the time to write mate
Mw is very useful other then kitchen use . We can melt glass very pure way
for sure mate
Thoughts on why I worried about it, Father was changing a battery on a truck and he got stuck to it for a moment. Now that I see you touching them, well he must have been holding a hotline that something was pulling from. Thanks for the un-fusion!
for certain he was mate - what quite often happens is the terminals get bridge by the spanner folks are using to disconnect the lugs - that's why a lot of spanners for this job come with an isolated grip - it just prevents jumping the terminals with a lump of conductor
@7:44
Robert: "This side... certainly don't be afraid of it. THIS side of it..." (points to mains)
Me: "Be afraid... be VERY afraid." 😝
Even though I work with it, I've never gotten over my fear of mains supply side and don't think I ever will. This harkens back to my theater days when I did stage lighting, where all the banging around the equipment went through ultimately meant that at SOME point, you WOULD experience a shock while handling equipment. And I eventually did, twice.
At this age, I'm perfectly OK with being afraid of it, but I do agree that you should never let the fear stop you. Courage isn't the absence of fear but action in spite of it.
I really don't think you need be afraid of anything mate - cautious, aware, sensible - for sure - afraid - never - I have been shocked too and I used to work on 10,000V lines while they were live
sorry for the non technical group, what the heck are we doing here, making cheap power but you plugged it into the mains, what am i missing, whats the business after the transformer about just briefly could someone explain
I know that a cars alternator only uses 3 diodes to rectify voltage. Do you recommend 4 diodes because of the higher voltage and amperage?
you are awesome sir, love every video thanks.
Shield AND put a fuse or other overcurrent protection on that primary coil!
Another good donor for a 12v ps is a old pc. They will usually have one good for a minimum of 20a.
The PVC insulated wire you used for the secondary is rated for 85 degrees C max, and is totally unsuitable for a transformer. You should have used enamelled copper wire of appropriate diameter (or multiple parallel windings).
Also that flat pack bridge rectifier is very unlikely to be rated for 70 amps! That package is normally suited for maybe 8 to 10 amps continuous, even with good heatsinking. If you stated the part number people could check your specs and calcs. 🙂
Correct ❤I wonder why he did 🤔 say about this fact
The real current limit is the amp rating of the mains circuit you connect the primary to.
If one is planning on integrating this 12v rectified dc power supply with the HHO generator, then I suggest including a PI (capacitor inductor capacitor) filter to smooth out the rectified pulsed DC.
Pulsed DC has a lower RMS voltage than than its peek voltage. While pulsed DC will work. It spends a significant fraction of a half cycle lower than the voltage needed for electrolysis. Then the voltage rises to the peek quickly bypassing the ideal voltage and each over voltage × amp draw = additional waste heat. Using a smoothing PI filter helps hold the voltage much more steady so you can produce hydrogen and oxygen at your ideal voltage much more of the time during each half cycle with less overvolting.
cheers mate
Thanks for addressing this. I was going to ask if this was somehow unnecessary for this application, but you've answered that, and explained why it's important.
Can you (or someone) please tell me what capacitors and inductor I should use for this project (types, values, ratings etc.), or perhaps how this is determined?
Thank you!
I made one of these its output measure's DC volts 12.8v but when I attach it to my design HHO generator with pulsed (12v 40 amp relay) the voltage reading changes to 18v Dc what is the explanation is my HHO generator generating output?
I didn’t get how the wire was added to the transformer, is the transformer left intact but with the extra wire wound through it?
Tested at 11.2V. Wouldn't you need to ADD one turn to bring it UP to 12V?
Use magnetic over current plunger cutoff switch instead of one time usable fuse
nice one mate cheers
What is that?
@@LEO-xo9cz Electromagnetic coil with high current wire when current reach to desire value , generated magnetic fields will pull the spring attached metal "switch " simple to make using wire iron and spring
@@omsingharjit So it's basically a relay.
@@LEO-xo9cz A circuit breaker :) most Circuit breakers have a thermal and magnetic circuit
PC power supply?
I just want to ask who has re-worked a PC power-suply or any other switching supply to adjustable voltage and current limitation?
They are even rated for their efficacy class, and you can find them from any junk yard.
In future, I would like to dive into „steered rectifiers“ frim Power-MOSFETS, because we can cut down the voltage drop of the diodes they replace. Probably need a potential free DC DC module for the gate potential, that surpasses the +, but any cheap one or recycled from old boards will do.
Even AD’s iCoupler have some mA to spare on the other side - 2.5kV isolated.
Don't you need to multiply it by sqrt(2) to get the peak DC voltage? 12v ac rectified will give you about 17v DC.
Yep, the RMS
Edit: my bad, it's not sqrt(2). It's the inverse of sqrt(2), so for 12V, it'd be round about 8.5V minus any drop from the rectifier
What if i put a powerful led light on it, one that can draw more amps, exceeding the bridge rectifiers amperage. Would the bridge rectifier burn out? Or would it hold strong at the bridge rectifiers amperage limit? Also, you say be careful with ac. So if i touch the secondary coil while the primary coil is plugged into 120v ac. Im dead right? I can never wrap my mind around what shocks me and what protects me. Or how to entirely be protected while also touching it or... idk. I wish i understood it.
After removing the secondary coil I tested the primary using 240V. After 30 mins. the temperature had risen to just under 100C. That's no load whatsoever. The primary uses around 70Watts no load, this may not sound much but it's all going into that small primary. The only real answer is to add more turns to the primary but that's messing about with mains Volts, unless you really know what you are doing make sure your will is up to date. It did seem to stabilise at around 100C but what happens when the secondary is used I have not yet tested. 'China Syndrome' ? - 'Frying Tonight' ?
Is it possible to get opposite result? Placing 12V battery to the end and connecting with secondary, turning 12VDC to 240 VAC from primary transformer?
Nice. Also, would it make sense to get some seriously rated connectors that go to the rectifier? If someone is going to be pulling 40-60 AMP's are 12vac, any chance they would heat up enough to melt a straight soldered connection? Pro-tip- lots of people will smash flat some copper pipe to use as lug/connectors on battery banks.
nice one. mate - me too by the way
Soo... are you going to demonstrate it in action?
Hello Robert,
can you make a video on glass battery?
sure
You should not use an extension cord on a reel like that for anything that draws a lot of power. It will overheat and I've actually seen the cords melt (with smoke and sparks flying soon thereafter)...
Wish I would have known this long ago, been using computer power supply's for years to power 12v & 5v goodies.
it's cheap and simple mate - it is for certain reusing a pc power supply gives you a much more stable and efficient supply - but sometimes that doesn't matter so much and cost and simplicity do - it all depends on what you want really
Do you remove the center connecting wire and the plates in between
I know people have been calling you a massive resistance, but don't let it get to you! You're better than that!
;'))
lol - nice one mate lol
Brilliant. I've got a couple of those lying around that I was going to use for Liechtenstein burning. Now I'm thinking of making an AC/DC supply for Etching, Plating and Anodising.
Could you do a video on something like that?
How can I add voltage and current controls with a display?
For the record a neon sign transformer is much safer and more effective at wood burning. I'd advise following your current plan to make a high current supply instead of burning wood with the microwave transformer. Oh, and for old neon sign transformer, get a old transformer type one, not a new one with open circuit detection as those won't work for it.
@@theLuigiFan0007Productions What is different about the neon?
@@LEO-xo9cz A microwave transformer outputs 2.3kV at around 400-800mA. A neon sign transformer has got a much higher voltage (about 3.5X) and much lower maximum possible current output, around 10-30mA in most cases. It's far less likely to instantly kill you in the case of a mishap and you get shocked. It's also better ar burning the wood as the voltage helps it get across better and the lower current helps preserve the finer details in the marks.