@@brainiac75 There’s no problem when watching your video since I subscribed to you years ago way before I subscribe to him. Also never comes into my mind that your video is a “lesser” quality compared to him.
@@brainiac75 You each excel in your niche! It's like comparing fast food restaurants. Despite often serving similar foods, they each have their own way of doing things that makes them better compared to others. I enjoy all my favorite creators' videos, all for different reasons.
Heating 300g of water by 10°C requires 12 600J of energy. The second microwave taking a full minute to do this means that its effective power is only 210W.
Probably, the smoothing oil capacitor is defective. The lower output matches the difference between the power output with the full DC voltage, and the pulsed but not smoothed voltage...
most modern microwaves have a sticker inside the door somewhere saying that u should put a spoon into the cup if u are heating water, because water on its own doesnt absorb much power, i usually only need like 1-2 minutes to get a cup to boil with a spoon in it, without one it takes way longer
@@dirtypure2023No, he's right. A spoon isn't sharp enough to cause issues. The problem is flash boiling (or however it's called in English, in German it's Siedeverzug). A spoon will help with that so that you won't end up with boiling hot water on your skin. But that's the reason they recommend it not the increased transferred power.
I bought an inverter powered microwave in 2018. It was just like the ovens used at work for many years and I considered it very reliable. 1200 Watt. Very happy with it. In 2022 I bought a group of magnetic strips that are screwed to a cabinet or other suitable support and are used for holding knives, forks, etc. One very useful place was the side of the oven. It holds very well without any screws. Everything was fine until I needed to cook a roast for over 2 hours. Suddenly the oven interior was filled with electrical component smelling smoke and the oven suddenly went dark. Pulling off the cover I found that the inverter transformer was within an inch of the side of the case. The windings were thoroughly cooked. Suspecting the magnetic field caused the high frequency inverter to saturate (I designed power supplies among other things before retiring.) I bought another identical oven. I monitored the power while heating water and approached the oven side with the same magnet strip. Sure enough, the power went up over the oven rating about 15%. The electronics must have been robust enough to survive short cooking times but overheated and smoked on long sessions. Lesson learned.
I was involved in the design of a powered loudspeaker (still am) with a SMPS and similar issue. The woofer magnet was causing the SMPS primary transformer to go into saturation, you're basically pulling the operating point of the core up the BH curve. Simple fix was simply to swap the polarity of the magnet and reverse the drive to the voicecoill and problem solved. You probably just had the misfortune of the knife magnets pulling the core in the direction of the DC bias operating point resulting in the AC excursions possibly going well into saturation in one direction.
Interesting! I guess high frequency transformers are more sensitive, because they use ferrite cores instead of the typical iron cores in low frequency ones. Ferrite can't be magnetized as much before it saturate, compared to iron. This is not much of a problem for a SMPS - as the operating frequency is so high that not much inductance on the primary winding is needed and thus, few turns (the much higher losses an iron core would have at these frequencies, due to eddy currents, would be much more of a problem). But when it comes to external magnetic fields, this means it takes less to cause a significant "offset" in core magnetization (causing the core to saturate each half cycle when the mangetic field from the magnet aligns with the one from the magnetizarion current in the primary winding - causing huge current spikes). Also, SMPS transformers are much smaller, so it also takes a smaller magnetic field to saturate a significant part of the core (not by the means of magnetic flux density of the field, but the area/volume of it) - thus it takes a smaller magnet to do damage. That extra 15% power draw was probably mostly the increased losses in the transformer - which caused it to slowly bake until it got an insulation failure causing an internal short circuit - which in turn caused the transistors in the inverter bridge to blow up.
@@Speeder84XL not always ferrites, it’s pretty common to used powdered metal (iron, aluminum, nickel, silicon blends etc) cores as well. They’re basically one giant distributed gap but with better HF performance because the granules are so small. They of course have lower mu than ferrites and should be less susceptible but are nevertheless susceptible. A large permanent magnet will likely saturate or nearly saturate the core so badly that the winding inductance falls precipitously because you’re operating in the flattened asymptotic part of the BH curve. mu = B/H if the slope of the line falls to zero so does mu and so your winding basically looks like an air core inductor more or less. This saturation issue is part of why DC offset in mains can wreck havoc with linear psu’s that use typical iron laminate transformer cores, not much current will create enuf DC bias to saturate the core. Depending on the winding resistance it’s not hard to get there esp with so many turns the magnetization force gets very high very fast.
@@JamesReedy Yes, but those iron powder cores and other similar are mostly used for just inductors, as they have a lot of leak inductance and gives poor coupling between primary and secondary when used as a trasformer (because as you said, they are like one giant distributed gap). For inductors in buck/boost converters and smoothing inductors (LC filters to reduce noise/ripple, current spikes) or similar, they are perfect though - as they can handle more before saturation and still increase the inductance a lot compared to air core coils, with low losses at high frequencies. As he wrote it was the transformer that got burnt out, it most likely had a ferrite core or a material with similar properties. I have cheap china heat gun where the power can be set at "full" or "half" - for the half power setting, there is just a diode blocking one half wave. This creates a DC offset on the line because of the assymmetrical voltage drop. If using that on half power setting, any 50 Hz transformers connected to the same line start to make a lot of noise caused by the current spikes as it saturates at each half wave that aligns with the DC component.
The magnet inside of a magnetron is actually rather weak and is so out of necessity. The magnet has a field pattern that fits inside. It is to get the electrons to bounce back and forth inside the cavity. Kind of like photons in the mirror box of a laser.
Try measuring the actual powerconsumption of the microwaves. Have sadly noticed that a lot of modern appliances simply lie about their actual power (like a food processor claiming 1600W but never reaching even 1400W).
I remember the start of that nonsense, instead of going with the normal RMS power, they started advertising peak to peak power, to get a higher number to report, while still churning out the same effective average power...
Pretty sure the ratings are meant to be a maximum and it will increase the more torque is required to process the food. Also will vary depending on input voltage. So no, they aren't necessarily lying.
ha! We had a SHARP microwave bought in Germany when I was a kid. Parents bought it in like '93. It was used almost daily and we had to replace it only in 2017. The light stopped working a long time ago, the rotating glass saucer broke 2 times (had to be replaced) but that microwave just kept going for over two decades. It even had a grill/broiler. I miss it.
Same here 97' sharp R series with grill. It is working till now daily used ~2 times per day without even one element replaced. Daimond star for the panzer quality Even "autocook" still working perfect.
I have an R series Sharp from 2005 and aside from the light giving out it's been a very durable unit. I've even run it straight from a generator several times and no issues. I love the unit and I'll be sad when it eventually dies.
I still can't believe this channel isnt very famous yet, this guy put a lot of dedication on every single video, honestly its a bit sad that science channels are that famous. I also think that if you also did more experiments with electricity it would be great
Thanks. I might be too safe and educate too much in my videos ;) I do have some electronics related video planned. Involves special lasers, high-powered PA amplifiers etc. But have patience as always ;)
@@brainiac75 Educate too much? No, it is spot on. That is how you do your content and it is absolutely great. Without the education, some videos do not make much sense. So keep that going. Great job and video.
heres an explanation for the resetting issue, its likely the switching power supply that powers the control board randomly cutting off because of the saturated core of the trasformer. the chips are powered off of a third winding on the transformer and starts with a resistor that charges the capacitor the chip is powered off of, it may be that its just saturated enough for the chip to stop running but the resistor is barely keeping it running. if it stops running, the resistor charges the capacitor up again due to the chip being in standby and drawing less current. the capacitor is charged up above the minimum voltage the chip requires to start because of a small delay(the amount of time the chip takes to start up). once the chip starts, it draws more power and the capacitor starts to discharge. at some point, its gonna discharge enough for the chip to shut down and the cycle repeats. its sort of like when the diode responsible for charging the capacitor fails and the chip is only running off of the resistor. in that case, you would have a power output that turns on for a few hundred milliseconds and turn off again. a second later, it turns on for a short time again. this effect is often called the "hiccup" failure and is why you often see lights flashing like that.
Saturated cores can act weird to begin with, far beyond any bias effect, as the entire hysteresis curve gets thrown off by the core being magnetically saturated. Inverters especially would be sensitive to that effect, as they'd never come close to operating in saturation to begin with. Line transformer based can operate closer to saturation, as that would help regulate the output of the transformer. I've worked with a handful of different classes of transformers over the decades, from saturation resistant types, various RF types, power transformer types, HF switching for SMDS/inverter systems and saturable reactors. For the most part, the math behind most is fairly straightforward. It's not as if it involved calculus with a half dozen elements.
Transformer-based microwave ovens are pretty nasty loads when they start. Most consumer-grade timers won't survive many cycles before their tiny relay rated for purely resistive loads like lamps and heaters fails.
Definitely not recommended for the inexperienced ;) Luckily, distance is your friend with magnetism (and radioactivity). As long as the magnet is at some distance from thick metal, the forces can be managed. The magnet is not stronger than what it can act upon. Thanks for watching!
With the horizontal magnetron, I think I would have tried the magnet, on top, but standing on edge, so that its fringes would pass through the magnetron in either aiding or reverse direction.
Yeah, got pinched a couple of times with mine. But, great for some experiments and also for general utility, such as clamping ferromagnetic objects in place that you don't really care if they get magnetized (although, degaussing them is simple enough too). Next projects, pick up some old microwaves for the power supplies... Might keep a magnetron for the beryllium oxide based insulator as well. Useful for a radiation reflector and general purpose insulator. Also toxic as hell, so care would be the watchword.
Thanks. There's no reason to trust the terrible timer on the microwave as you could instead use a timer on your phone and either switch off the power or open the door when the timer expires. Keep the phone away the magnet, though.
Relevant sponsors are much more better than the shady ones most UA-camrs use. And styropyro proved that non-ionizing radiation can be quite fun when run at very high intensities.
Placing the glass in the middle means it stays stationary, and because microwaves have peaks and troughs, it's pretty likely that your new microwave oven just generates waves in a way that causes the center to heat up less. You can search for hot spots by just placing a chocolate bar inside and seeing what spots melt/get burnt, and you can remove the rotating platform altogether.
But it's not stationary as plate inside rotate. Glass should be big and tall enough to be catching wave spot on it and be hit from different sides during heating.
Yes, it is one of the suspicions I mention in text. Will have to try to locate the hotspots in the two ovens. The old one might have an undesired hotspot at the center of the plate, while the new one was designed to avoid this food-burning spot. I do note that the old one has very flat sides inside, while the new one has more 'facets' on the inside. Thanks for watching and the suggestion!
@@paranoiia8 Yeah, but it's not moving in space. It's just rotating around it's own axis. The rotating plate is there to move whatever you put inside in space, because that's when the object gets exposed to various points of intensity.
I think it'd be cool to use a thermochromic paint or something to map the hot/cold spots inside the microwave then put the magnet next to it to see how the field messes with the waveform
Easily got my thumbs up! Was no stupid music, narrated by a real person and not ai, a lot of detail making it interesting to follow along, and just a down-to-earth video. Thanks for sharing !
I very much appreciate you not literally disassembling the microwave (other than the cover to identify the parts) very cool video as always, great work! Also, that geiger counter is absolutely gold
Thanks :) I don't like how people are taking magnetrons apart to salvage the 'strong' magnets inside them. They are very cheaply available as ferrite ring magnets for small speakers. And not strong... The magnetron is worth much more in working condition :D Yep, I love the RadiaCode dosimeter/spectrometer (can be used as a Geiger counter as well).
Congratulations to your experiments, very much straight forward. When playing with microwave ovens I placed a diode and a µA meter at some point of the door-slit where the microwaves can be detected to get an immediate reading for the power. (Any other slit can be made and closed afterwards.) I checked the power while changing the supply voltage with a variable transformer to measure the field distribution inside.
You could try a modern inverter powered microwave. Then you wouldn't have to worry about the transformer. Dont know if the cost can be justified though.
Inverters still use a transformer, just that it's not driven at mains frequency. They're slightly more energy efficient, use a smaller core in the transformer and less copper in the windings, which are the main reasons manufacturers went with them, not the efficiency, less expensive materials.
If you are worry about the transformer being too close to your test, take it out, make the cables longer and let it work outside the microwave. I guess you can do the same for all the other components like the capacitor and motherboard, leaving only the magnetron inside to be abused.
I am always amazed at the sheer strength of those magnets. Just watching how you have to take so much care and mechanical manipulation to work with them blows my mind.
Repeatability isn't just about the time, there are nodes and anti-nodes in the microwave so unless you place the cup precisely that's another reason you could see variances in the heating of the water.
I know this is the first comment, but from your last video where magnets meet a plasma globe, I’m sure the magnet interferes with the transformer’s ability to do it’s job and cause the microwave to struggle!
Yes, no doubt that the transformer is affected too. But not that much - at least in the case of the old one. Notice the limited drop in output in the 'right polarity'-test. It would not work that well with a saturated transformer core. With that said, a future improvement could be to separate the magnetron from all other components by long wires. A little daunting though... Thanks for the early watch and comment, AluminumOxide!
@@brainiac75 I didnt watch the video yet,but one huge safety issue i see here: Magnetrons operate with a voltage of 3kV. Nornally when the magnetic field inside the magnetron is present, the electrons will circle around the center. So when they get near the outer copper ring, they only have a tangential curve to it, and dont smash into it. However when you encounter that magnetoc field with your magnet, the elecrons will crash into the copper with an energy of 3keV This should be enough to generate some low energy Röntgen radiation,as the spectrum starts at 125eV. Normally Röntgen radiation is created with 30KV, but still 3kV might be enough for a harmful amount of radiation
@@larslindgren3846 You are right. I just searched for the Apsorption koefficient of copper at 3keV. It turns out to be 6700 cm^(-1) So the thick copper body of the magnetron will already block it completely. For iron it is a little bit lower, but still high enough. So you are right it will not exit the microwave.
You probably just disabled the power on relay with your strong magnetic field. You could try a simpler manual microwave oven (the ones you rotate the button an set a mechanical timer), they dont have electronics.
As far as I remember, the magnetron structure consists of a number of cavities and the frequency depends on the speed an electron beam travels past the cavities. The magnetic field is what causes the beam to rotate. You can deflect the beam sideways causing the beam to miss the cavities entirely, or you can possibly change the resulting frequency, de-tuning out of the wave guide, causing change in coupled energy.
Maybe gutting out transformer and electronic putting it on the side so just magnetron is in original place, and then try it? It will need some work as you would need to extend some wires and probably also remove control panels(so pretty much damaging microwave enough to not be able to put it together again)... Not sure if it's worth but... Maybe...
The giant magnets scare me almost as much as mains and high voltages. I have so much ferrous stuff about my work areas it would require clearing a huge area and I'm sure there would be random metal filings and weld beads that would be missed. Interesting video, mate :)
I mean, less hassle. The simpler the better. Like involving power meters, etc. He usually reviews with more sophisticated techniques if there's enough demand. He more looks for OBVIOUS things though - ones that don't require excessive shenanigans.
I'm sure that microwave has a switch mode power supply for the electronics. These contain transformers or at least inductors. If properly dimensioned in operation the inductors are close to but not at magentic saturation. If you add a magnetic field from the outside they will be closer to saturation and no longer work as inductor/transformer (or rather they behave like an inductor without core, which has a much lower inductance). Essentially you stopped the inductor's/transformer's ability to store or transfer the intended power.
I own several neodymium magnets of 30mm x 10mm and in a single moment of inattention I managed to give myself a blood blister when two of them snapped together. Brainiac's monster magnet terrifies me.
Thank you! I need to go into more details about how a magnetron works, but this video is long enough as is. And magnetrons are not that easy to understand and explain in a simple way :/
If you apply the magnets directly to the magnetron only on top or only on bottom you can bias the internal magnetic field and cause the electrons to only ever make ~1 loop. In normal operation they make many and so having lost energy each loop, they become different frequencies. So by biasing one pole with a strong external magnet you can improve the spectral purity of the magnetron output.
I got a bit flabergasted when I saw the caption mentioning the Monster magnet vs server video dated 2016. It's crazy to realize how long I have enjoyed the videos. Time flies 🚁
The field strength in microwave ovens is uneven, there are spots with higher and lower strength, due to interference caused by the microwaves bouncing around the chamber. That's why they have a rotating plate. It is possible that the new microwave has a very weak spot right in the middle, which negates the effect of the plate's rotation if you put something right on the middle of it.
When you removed the magnet at 4:57, the cooling fan in my computer shut off (kind of creepy that it happened at the exact moment the magnet was removed)
It makes me smile that you have a crazily impressive neo magnet - but seem to lack a £1 digital timer to make accurate timing of the old analogue microwave - or even a kitchen clock with a second hand!
Will the microwave work? I think it depends if you align your super magnetic field with the magnetic field in the microwave. If they oppose each other, then no!
The magnet was likely affecting the output power of the standby power supply in the microwave, causing it to drop out and reset, as well as behave audibly when trying to pull in the relay, if it's a switchmode supply
Older microwave ovens are much better than new ones. You get more power from the magnetron. Yes, the analog timer isn't perfect. But we aren't cooking gourmet food here 😂.
Interesting experiment! Can you place the magnet on top of the water (from the outside of course) and see if the additional magnetic field inside the heating region can create a cyclotron and further enhance the energy coupling to the water?
This video made me realize time is the only numerical measurement that's the same everywhere. No metric time its minutes hours, days etc. yet physical measurements are different With the expectation of electricity I think a different system for power could be dangerous if someone didn't convert it correctly thankfully it's using the same system.
I think you should take some fabric like ripstop codura of similar and sew a cover with handles for this magnet. (Or ropes with knots, so you don't put hand inside of handle) It will make nadling it WAY easier. This kinds of fabric will handle few hundred kilograms of force, so it will survive. And there are plastic needles that you can use for the last stitches to saw it shut, or use paracord to tie it, or a boat load of velcro :P I would even think of adding 2-3 strips of thick foam so in the unlikely event of finger getting where they should not, magnet will be lifted from the surface a bit (it should be a difference between healing and loosing fingers.
Take apart the magnetron. Replace both ceramic magnets with your ultra high powered magnets. See if it boils water faster. All these experiments should be done outside of the microwave. Use 2 momentary push button switches in series outside of the room to turn it on. If one switch fails closed circuit there is a second switch keeping the circuit open.
I think putting the water in the center of the microwave may be undermining the rotating plate.The wave formations in a microwave have hotspots and the plate spinning allows the thing thats being heated to rotate through hot and cool spots evenly for more consistent heating.
You could always just bypass that relay and use an external timer, However I would also remove the transformer and run it externally, about a meter away from your magnet, as it would most likely just saturate with that intense field and just blow a fuse. Your only problem is getting some high voltage rated wire, however considering all the other kit you have, no real challenge.
Very few things scare me in this world but they are in order being high up, electricity, large compressed springs, very large mangets, deep water, dark open space
Reguarding differences in temp and differences in old and new ovens. i doubt the watts per liter is actually making a significant difference. My reasoning is that even though there is greater volume in the new, it simply means the microwave energy might bounce around more before being absorbed by the cup of water. I think the differences in power is likely more to do with the transformers as you pointed out. You could probably swap the transformers easily. At least temporarilly move the trabsforner to prevent saturating its core material.
I always thought my parents were exaggerating when they said "They don't build them like they used too". I'm finally realizing that maybe our parents actually know what they are talking about.
At the old microwave you can "Skip" the timer if you setit to a long time and switch the microwave with an external power switch manually. So you get 1min runtime always.
You need one of those magnetic films you can see the magnetic flux lines and see how it's impacting the microwave, the microwave might be working like a Faraday cage aswell
It’s a good thing he’s wearing slippery socks on very smooth surfaces while putting tons of energy into pulling magnets from metal while on a table! Nothing can go wrong there!
The new microwave resetting is probably due to the small transformer for the timer saturating Possible improvements: Offset the glass on the rotating table from the center so that it can sweep thru hot and cold spots of radiation in the microwave Turn on the old microwave and switch its power at the socket to get exactly 1 minute
Been a subscriber of your channel for years and love your experiments. Where do you get strong neodymium magnets from please & how do you know what the various magnet codes mean? Best wishes from here in the UK.
I pushed my Radiacode 103 to its limit recently with an old Chirana X-ray tube. It maxed out at 1mSv/h with over 3 million CPM. If you’re wondering I have a remotely operated switch, so I don’t have to be anywhere near it when it’s running.
putting the magnet on the side with the transformer will just definitely smash the casing and probably cause a short somewhere, nevermind turning off the transformer :D
We had a Kitchen Aid microwave that started misbehaving in a very weird way. Sometimes instead of heating food up, it bizarrely actually made the food colder. Can't wrap my head on how that is possible. You could always tell when it wasn't working properly as it made a different sound.
@@Basement-Science Tell that to the food that got colder. The food was room temperature before putting it into the micro but ws colder when I took it out.
I love when after I watch from styropyro new video about microwaves this video pops out in my recommendations
Nice coincidence. Hope my video is OK after watching one of his quality videos :D
@@brainiac75 There’s no problem when watching your video since I subscribed to you years ago way before I subscribe to him. Also never comes into my mind that your video is a “lesser” quality compared to him.
@@brainiac75they're equally awesome, you're like our European styropyro
@@brainiac75 You each excel in your niche!
It's like comparing fast food restaurants. Despite often serving similar foods, they each have their own way of doing things that makes them better compared to others.
I enjoy all my favorite creators' videos, all for different reasons.
SAME
Heating 300g of water by 10°C requires 12 600J of energy. The second microwave taking a full minute to do this means that its effective power is only 210W.
Probably the smoothing capacitor is defective.
Probably, the smoothing oil capacitor is defective. The lower output matches the difference between the power output with the full DC voltage, and the pulsed but not smoothed voltage...
most modern microwaves have a sticker inside the door somewhere saying that u should put a spoon into the cup if u are heating water, because water on its own doesnt absorb much power, i usually only need like 1-2 minutes to get a cup to boil with a spoon in it, without one it takes way longer
@@BadMax02_VR No one listen to this lol. Don't put metal in a microwave!
@@dirtypure2023No, he's right. A spoon isn't sharp enough to cause issues. The problem is flash boiling (or however it's called in English, in German it's Siedeverzug). A spoon will help with that so that you won't end up with boiling hot water on your skin.
But that's the reason they recommend it not the increased transferred power.
I bought an inverter powered microwave in 2018. It was just like the ovens used at work for many years and I considered it very reliable. 1200 Watt. Very happy with it. In 2022 I bought a group of magnetic strips that are screwed to a cabinet or other suitable support and are used for holding knives, forks, etc. One very useful place was the side of the oven. It holds very well without any screws. Everything was fine until I needed to cook a roast for over 2 hours. Suddenly the oven interior was filled with electrical component smelling smoke and the oven suddenly went dark. Pulling off the cover I found that the inverter transformer was within an inch of the side of the case. The windings were thoroughly cooked. Suspecting the magnetic field caused the high frequency inverter to saturate (I designed power supplies among other things before retiring.) I bought another identical oven. I monitored the power while heating water and approached the oven side with the same magnet strip. Sure enough, the power went up over the oven rating about 15%. The electronics must have been robust enough to survive short cooking times but overheated and smoked on long sessions. Lesson learned.
I was involved in the design of a powered loudspeaker (still am) with a SMPS and similar issue. The woofer magnet was causing the SMPS primary transformer to go into saturation, you're basically pulling the operating point of the core up the BH curve. Simple fix was simply to swap the polarity of the magnet and reverse the drive to the voicecoill and problem solved. You probably just had the misfortune of the knife magnets pulling the core in the direction of the DC bias operating point resulting in the AC excursions possibly going well into saturation in one direction.
Interesting!
I guess high frequency transformers are more sensitive, because they use ferrite cores instead of the typical iron cores in low frequency ones. Ferrite can't be magnetized as much before it saturate, compared to iron. This is not much of a problem for a SMPS - as the operating frequency is so high that not much inductance on the primary winding is needed and thus, few turns (the much higher losses an iron core would have at these frequencies, due to eddy currents, would be much more of a problem). But when it comes to external magnetic fields, this means it takes less to cause a significant "offset" in core magnetization (causing the core to saturate each half cycle when the mangetic field from the magnet aligns with the one from the magnetizarion current in the primary winding - causing huge current spikes).
Also, SMPS transformers are much smaller, so it also takes a smaller magnetic field to saturate a significant part of the core (not by the means of magnetic flux density of the field, but the area/volume of it) - thus it takes a smaller magnet to do damage.
That extra 15% power draw was probably mostly the increased losses in the transformer - which caused it to slowly bake until it got an insulation failure causing an internal short circuit - which in turn caused the transistors in the inverter bridge to blow up.
@@Speeder84XL not always ferrites, it’s pretty common to used powdered metal (iron, aluminum, nickel, silicon blends etc) cores as well. They’re basically one giant distributed gap but with better HF performance because the granules are so small. They of course have lower mu than ferrites and should be less susceptible but are nevertheless susceptible.
A large permanent magnet will likely saturate or nearly saturate the core so badly that the winding inductance falls precipitously because you’re operating in the flattened asymptotic part of the BH curve. mu = B/H if the slope of the line falls to zero so does mu and so your winding basically looks like an air core inductor more or less.
This saturation issue is part of why DC offset in mains can wreck havoc with linear psu’s that use typical iron laminate transformer cores, not much current will create enuf DC bias to saturate the core. Depending on the winding resistance it’s not hard to get there esp with so many turns the magnetization force gets very high very fast.
@@JamesReedy Yes, but those iron powder cores and other similar are mostly used for just inductors, as they have a lot of leak inductance and gives poor coupling between primary and secondary when used as a trasformer (because as you said, they are like one giant distributed gap). For inductors in buck/boost converters and smoothing inductors (LC filters to reduce noise/ripple, current spikes) or similar, they are perfect though - as they can handle more before saturation and still increase the inductance a lot compared to air core coils, with low losses at high frequencies.
As he wrote it was the transformer that got burnt out, it most likely had a ferrite core or a material with similar properties.
I have cheap china heat gun where the power can be set at "full" or "half" - for the half power setting, there is just a diode blocking one half wave. This creates a DC offset on the line because of the assymmetrical voltage drop.
If using that on half power setting, any 50 Hz transformers connected to the same line start to make a lot of noise caused by the current spikes as it saturates at each half wave that aligns with the DC component.
What you have there is a coincidence.
If you collaborated with your magnets and styropyro’s 20kw microwave, that would be nuts 😂
Monster magnet meets MACROwave
You'd need an even more monster magnet! Maybe an electromagnet powered by Styro's bank of car batteries.
@@gcewing dont give them ideas
The magnet inside of a magnetron is actually rather weak and is so out of necessity.
The magnet has a field pattern that fits inside.
It is to get the electrons to bounce back and forth inside the cavity.
Kind of like photons in the mirror box of a laser.
Try measuring the actual powerconsumption of the microwaves. Have sadly noticed that a lot of modern appliances simply lie about their actual power (like a food processor claiming 1600W but never reaching even 1400W).
a classic example of "take the government to the bin because all they're doing is nomming money"
I remember the start of that nonsense, instead of going with the normal RMS power, they started advertising peak to peak power, to get a higher number to report, while still churning out the same effective average power...
@@spvillano That's the worst with consumer grade anything
For safety of your electric installation, it is better this way than the other.
Pretty sure the ratings are meant to be a maximum and it will increase the more torque is required to process the food. Also will vary depending on input voltage. So no, they aren't necessarily lying.
ha! We had a SHARP microwave bought in Germany when I was a kid. Parents bought it in like '93. It was used almost daily and we had to replace it only in 2017. The light stopped working a long time ago, the rotating glass saucer broke 2 times (had to be replaced) but that microwave just kept going for over two decades. It even had a grill/broiler. I miss it.
Mine is nearing 20. They are really sturdy appliances.
Same here
97' sharp R series with grill. It is working till now daily used ~2 times per day without even one element replaced.
Daimond star for the panzer quality
Even "autocook" still working perfect.
I have an R series Sharp from 2005 and aside from the light giving out it's been a very durable unit. I've even run it straight from a generator several times and no issues. I love the unit and I'll be sad when it eventually dies.
Mine's a no-name brand, I bought the cheapest I could find, still going strong like 17 years later
Uploaded one minute ago, and my dinner is ready to eat.. perfect timing
17:17 Microwave the magnet ;-)
I still can't believe this channel isnt very famous yet, this guy put a lot of dedication on every single video, honestly its a bit sad that science channels are that famous. I also think that if you also did more experiments with electricity it would be great
Thanks. I might be too safe and educate too much in my videos ;) I do have some electronics related video planned. Involves special lasers, high-powered PA amplifiers etc. But have patience as always ;)
@@brainiac75 Educate too much? No, it is spot on. That is how you do your content and it is absolutely great. Without the education, some videos do not make much sense. So keep that going. Great job and video.
The science channels that are very popular are either very high on the entertainment spectrum, or they're plants like veritasium.
That's 781000 subs not 781
heres an explanation for the resetting issue, its likely the switching power supply that powers the control board randomly cutting off because of the saturated core of the trasformer. the chips are powered off of a third winding on the transformer and starts with a resistor that charges the capacitor the chip is powered off of, it may be that its just saturated enough for the chip to stop running but the resistor is barely keeping it running. if it stops running, the resistor charges the capacitor up again due to the chip being in standby and drawing less current. the capacitor is charged up above the minimum voltage the chip requires to start because of a small delay(the amount of time the chip takes to start up). once the chip starts, it draws more power and the capacitor starts to discharge. at some point, its gonna discharge enough for the chip to shut down and the cycle repeats. its sort of like when the diode responsible for charging the capacitor fails and the chip is only running off of the resistor. in that case, you would have a power output that turns on for a few hundred milliseconds and turn off again. a second later, it turns on for a short time again. this effect is often called the "hiccup" failure and is why you often see lights flashing like that.
Saturated cores can act weird to begin with, far beyond any bias effect, as the entire hysteresis curve gets thrown off by the core being magnetically saturated. Inverters especially would be sensitive to that effect, as they'd never come close to operating in saturation to begin with. Line transformer based can operate closer to saturation, as that would help regulate the output of the transformer.
I've worked with a handful of different classes of transformers over the decades, from saturation resistant types, various RF types, power transformer types, HF switching for SMDS/inverter systems and saturable reactors. For the most part, the math behind most is fairly straightforward. It's not as if it involved calculus with a half dozen elements.
This is not how it works at all, and they never use the main transformer to power the electronic board.
@AeroGraphica you can see the switch mode power supply below the relay at 16:18
Could try using the analog microwave with an on/off power strip and use a timer for 60 seconds.
Right? Or if he wants it automated, a smart plug and set a timer in the app.
Or simply use a stopwatch (on a phone) and switch off digitally (using human finger).
Transformer-based microwave ovens are pretty nasty loads when they start. Most consumer-grade timers won't survive many cycles before their tiny relay rated for purely resistive loads like lamps and heaters fails.
yes
@@teardowndan5364 just use a relay to power the high voltage part
picking up the monster magnet from the top of the microwave looked scary... if that thing had tipped to a side it would've crushed your fingers
😱
Definitely not recommended for the inexperienced ;) Luckily, distance is your friend with magnetism (and radioactivity). As long as the magnet is at some distance from thick metal, the forces can be managed. The magnet is not stronger than what it can act upon. Thanks for watching!
@@brainiac75 I've long said, the inverse square law is my frenemy. ;)
@@brainiac75 Thank Isaac Newton for his inverse square law!
Your magnet pulled the door, safety switches into the off position. Lol
Would be more fun if you were to trip the "monitor" switch while the microwave is running. A bang and a dead microwave would result.
Thanks!
Thank you @mehamrdio6173 Glad you liked the video enough for a Super Thanks! More magnet videos to come :)
With the horizontal magnetron, I think I would have tried the magnet, on top, but standing on edge, so that its fringes would pass through the magnetron in either aiding or reverse direction.
Luckily your safety socks prevented your toes from being injured while separating the magnet from the microwave.
Handling a magnet this strong is so scary 😰
Yeah, got pinched a couple of times with mine. But, great for some experiments and also for general utility, such as clamping ferromagnetic objects in place that you don't really care if they get magnetized (although, degaussing them is simple enough too).
Next projects, pick up some old microwaves for the power supplies... Might keep a magnetron for the beryllium oxide based insulator as well. Useful for a radiation reflector and general purpose insulator. Also toxic as hell, so care would be the watchword.
Thanks. There's no reason to trust the terrible timer on the microwave as you could instead use a timer on your phone and either switch off the power or open the door when the timer expires. Keep the phone away the magnet, though.
Relevant sponsors are much more better than the shady ones most UA-camrs use.
And styropyro proved that non-ionizing radiation can be quite fun when run at very high intensities.
Placing the glass in the middle means it stays stationary, and because microwaves have peaks and troughs, it's pretty likely that your new microwave oven just generates waves in a way that causes the center to heat up less. You can search for hot spots by just placing a chocolate bar inside and seeing what spots melt/get burnt, and you can remove the rotating platform altogether.
But it's not stationary as plate inside rotate. Glass should be big and tall enough to be catching wave spot on it and be hit from different sides during heating.
Yes, it is one of the suspicions I mention in text. Will have to try to locate the hotspots in the two ovens. The old one might have an undesired hotspot at the center of the plate, while the new one was designed to avoid this food-burning spot. I do note that the old one has very flat sides inside, while the new one has more 'facets' on the inside. Thanks for watching and the suggestion!
@@paranoiia8 Yeah, but it's not moving in space. It's just rotating around it's own axis. The rotating plate is there to move whatever you put inside in space, because that's when the object gets exposed to various points of intensity.
Usually manufacturers recommend placing items as close to the edge of the rotating plate as possible, precisely for that reason.
the magnet holding the relay open was my first thought also.
even before seeing that part of the video😊
Test week in university for me, microwave obsession week for youtube! Magnetrons are truly fascinating and amazing
Good luck on your exams! We all know that you will do amazingly!
I think it'd be cool to use a thermochromic paint or something to map the hot/cold spots inside the microwave then put the magnet next to it to see how the field messes with the waveform
Easily got my thumbs up! Was no stupid music, narrated by a real person and not ai, a lot of detail making it interesting to follow along, and just a down-to-earth video. Thanks for sharing !
Thanks - I came across this whilst trying to fix my microwave, I've now moved my kitchen giant monster neodymiums and its working just fine. Top Tip!
I very much appreciate you not literally disassembling the microwave (other than the cover to identify the parts) very cool video as always, great work! Also, that geiger counter is absolutely gold
Thanks :) I don't like how people are taking magnetrons apart to salvage the 'strong' magnets inside them. They are very cheaply available as ferrite ring magnets for small speakers. And not strong... The magnetron is worth much more in working condition :D Yep, I love the RadiaCode dosimeter/spectrometer (can be used as a Geiger counter as well).
I love it when a professional channel meets a professional sponsor
Congratulations to your experiments, very much straight forward.
When playing with microwave ovens I placed a diode and a µA meter at some point of the door-slit where the microwaves can be detected to get an immediate reading for the power. (Any other slit can be made and closed afterwards.) I checked the power while changing the supply voltage with a variable transformer to measure the field distribution inside.
You could try a modern inverter powered microwave. Then you wouldn't have to worry about the transformer. Dont know if the cost can be justified though.
I've seen $80 inverter microwaves.
The weight reduction vs traditional magnetic, makes up the parts cost difference, with shipping weight reduction
On the plus side, these tests proved he _shouldn't_ need to rely on The Magic Of Buying Two Of Them...
Inverters still use a transformer, just that it's not driven at mains frequency. They're slightly more energy efficient, use a smaller core in the transformer and less copper in the windings, which are the main reasons manufacturers went with them, not the efficiency, less expensive materials.
@@WackoMcGoose technology connections
good sugestion
Big fan
One of the best UA-cam channel
Thank you very much! Perhaps also one the oldest, still active channels in this category :D
Great sponsor! Relevant, informative, and engaging - I watched through the whole thing 👌
If you are worry about the transformer being too close to your test, take it out, make the cables longer and let it work outside the microwave. I guess you can do the same for all the other components like the capacitor and motherboard, leaving only the magnetron inside to be abused.
I am always amazed at the sheer strength of those magnets. Just watching how you have to take so much care and mechanical manipulation to work with them blows my mind.
Another Brainiac video! Glad to see you back!
The fact that this guy still has both hands is magnificent
Repeatability isn't just about the time, there are nodes and anti-nodes in the microwave so unless you place the cup precisely that's another reason you could see variances in the heating of the water.
So what's your arm workout routine?
Brainiac: well I place and remove my monster magnet on top of my microwave, 4 reps seems to be enough.
I've upvoted because of the great literal effort moving the magnet in and out. You deserve it. I also commented so pappa algorithm rewards your vid.
I know this is the first comment, but from your last video where magnets meet a plasma globe, I’m sure the magnet interferes with the transformer’s ability to do it’s job and cause the microwave to struggle!
Yes, no doubt that the transformer is affected too. But not that much - at least in the case of the old one. Notice the limited drop in output in the 'right polarity'-test. It would not work that well with a saturated transformer core. With that said, a future improvement could be to separate the magnetron from all other components by long wires. A little daunting though... Thanks for the early watch and comment, AluminumOxide!
@@brainiac75 It would be interesting to see how this experiment affects the amount of current the microwave is drawing.
@@brainiac75
I didnt watch the video yet,but one huge safety issue i see here:
Magnetrons operate with a voltage of 3kV.
Nornally when the magnetic field inside the magnetron is present, the electrons will circle around the center.
So when they get near the outer copper ring, they only have a tangential curve to it, and dont smash into it.
However when you encounter that magnetoc field with your magnet, the elecrons will crash into the copper with an energy of 3keV
This should be enough to generate some low energy Röntgen radiation,as the spectrum starts at 125eV.
Normally Röntgen radiation is created with 30KV, but still 3kV might be enough for a harmful amount of radiation
@@neutronenstern. 3keV is dangerous but will not go through thin sheath metal. In this setup there are at least 2 layers.
@@larslindgren3846
You are right.
I just searched for the Apsorption koefficient of copper at 3keV.
It turns out to be 6700 cm^(-1)
So the thick copper body of the magnetron will already block it completely.
For iron it is a little bit lower, but still high enough.
So you are right it will not exit the microwave.
You could just turn analog microwave on, use any digital timer, and turn microwave off manually after minute to get much more precise timing.
You probably just disabled the power on relay with your strong magnetic field.
You could try a simpler manual microwave oven (the ones you rotate the button an set a mechanical timer), they dont have electronics.
As far as I remember, the magnetron structure consists of a number of cavities and the frequency depends on the speed an electron beam travels past the cavities. The magnetic field is what causes the beam to rotate. You can deflect the beam sideways causing the beam to miss the cavities entirely, or you can possibly change the resulting frequency, de-tuning out of the wave guide, causing change in coupled energy.
Maybe gutting out transformer and electronic putting it on the side so just magnetron is in original place, and then try it? It will need some work as you would need to extend some wires and probably also remove control panels(so pretty much damaging microwave enough to not be able to put it together again)... Not sure if it's worth but... Maybe...
I'm not sure he's experienced and comfortable enough with high voltage electricity (or even mains) to recommend this.
The giant magnets scare me almost as much as mains and high voltages. I have so much ferrous stuff about my work areas it would require clearing a huge area and I'm sure there would be random metal filings and weld beads that would be missed. Interesting video, mate :)
1:43 You were using the manual dial to time it, instead of a stopwatch or something? Why? =D
I mean, less hassle. The simpler the better. Like involving power meters, etc. He usually reviews with more sophisticated techniques if there's enough demand. He more looks for OBVIOUS things though - ones that don't require excessive shenanigans.
Really fun to see how a monster magnet interacts with the chefs of Olive Garden.
I'm sure that microwave has a switch mode power supply for the electronics. These contain transformers or at least inductors. If properly dimensioned in operation the inductors are close to but not at magentic saturation. If you add a magnetic field from the outside they will be closer to saturation and no longer work as inductor/transformer (or rather they behave like an inductor without core, which has a much lower inductance). Essentially you stopped the inductor's/transformer's ability to store or transfer the intended power.
Even a mains frequency based power supply transformer can be saturated by such a magnet.
I own several neodymium magnets of 30mm x 10mm and in a single moment of inattention I managed to give myself a blood blister when two of them snapped together. Brainiac's monster magnet terrifies me.
Marvelous, mesmerizing montage, masterfully made!
Styropyro would be scared of this
lol
Well, he doesn't come across as cautious to me ;) Thanks for watching!
I dont know, his most recent microwave is a bit over the top.
A perfectly matched colab waiting to happen!
Styropyro will microwave the magnet.
Love your videos and explanations
Thank you! I need to go into more details about how a magnetron works, but this video is long enough as is. And magnetrons are not that easy to understand and explain in a simple way :/
If you apply the magnets directly to the magnetron only on top or only on bottom you can bias the internal magnetic field and cause the electrons to only ever make ~1 loop. In normal operation they make many and so having lost energy each loop, they become different frequencies. So by biasing one pole with a strong external magnet you can improve the spectral purity of the magnetron output.
I thought this video was going to be about placing the magnet inside the microwave and switching on...
I got a bit flabergasted when I saw the caption mentioning the Monster magnet vs server video dated 2016. It's crazy to realize how long I have enjoyed the videos. Time flies 🚁
The field strength in microwave ovens is uneven, there are spots with higher and lower strength, due to interference caused by the microwaves bouncing around the chamber. That's why they have a rotating plate. It is possible that the new microwave has a very weak spot right in the middle, which negates the effect of the plate's rotation if you put something right on the middle of it.
When you removed the magnet at 4:57, the cooling fan in my computer shut off (kind of creepy that it happened at the exact moment the magnet was removed)
Pirostrio just made a 20,000 watt microwave. It was scary impressive, just like those neodymium magnets you use!
He used a HV line transformer from a power pole 🤣🤣
The day all 6 of your warning triangles are used will be scary.
It would've been a good addition to have a power meter plugged in to see if the extra magnet increases the power the microwave takes in
It makes me smile that you have a crazily impressive neo magnet - but seem to lack a £1 digital timer to make accurate timing of the old analogue microwave - or even a kitchen clock with a second hand!
Will the microwave work? I think it depends if you align your super magnetic field with the magnetic field in the microwave. If they oppose each other, then no!
The magnet was likely affecting the output power of the standby power supply in the microwave, causing it to drop out and reset, as well as behave audibly when trying to pull in the relay, if it's a switchmode supply
Older microwave ovens are much better than new ones.
You get more power from the magnetron. Yes, the analog timer isn't perfect. But we aren't cooking gourmet food here 😂.
Having gotten my finger stuck between two relatively small neodymium magnets from a HDD, I don't even want to imagine what these huge ones would do.
Interesting experiment! Can you place the magnet on top of the water (from the outside of course) and see if the additional magnetic field inside the heating region can create a cyclotron and further enhance the energy coupling to the water?
I love the "Video Tip". It reminded me so much of the Editor's Notes in any given American comic book.
This video made me realize time is the only numerical measurement that's the same everywhere. No metric time its minutes hours, days etc. yet physical measurements are different
With the expectation of electricity I think a different system for power could be dangerous if someone didn't convert it correctly thankfully it's using the same system.
I hadn't realized until now that the monster magnet is almost 30 pounds. That thing truly is ridiculous.
Styro and Brainiac releasing videos in succession
HUZZAH
I think you should take some fabric like ripstop codura of similar and sew a cover with handles for this magnet. (Or ropes with knots, so you don't put hand inside of handle)
It will make nadling it WAY easier.
This kinds of fabric will handle few hundred kilograms of force, so it will survive. And there are plastic needles that you can use for the last stitches to saw it shut, or use paracord to tie it, or a boat load of velcro :P
I would even think of adding 2-3 strips of thick foam so in the unlikely event of finger getting where they should not, magnet will be lifted from the surface a bit (it should be a difference between healing and loosing fingers.
Take apart the magnetron. Replace both ceramic magnets with your ultra high powered magnets. See if it boils water faster. All these experiments should be done outside of the microwave. Use 2 momentary push button switches in series outside of the room to turn it on. If one switch fails closed circuit there is a second switch keeping the circuit open.
I think putting the water in the center of the microwave may be undermining the rotating plate.The wave formations in a microwave have hotspots and the plate spinning allows the thing thats being heated to rotate through hot and cool spots evenly for more consistent heating.
PS : putting your spaghetti in a doughnut shape will allow it to heat evenly without the cold spot in the center.
My conclusion is that if someone tries to cook you in a microwave, having two giant neodymium magnets in your pockets might help.
You could always just bypass that relay and use an external timer,
However I would also remove the transformer and run it externally, about a meter away from your magnet, as it would most likely just saturate with that intense field and just blow a fuse. Your only problem is getting some high voltage rated wire, however considering all the other kit you have, no real challenge.
Try bridging the relay with some wires, solder them, connect them to a high voltage rated switch and manually trigger the relay that way
I saw you lifting the magnet barefoot and thought “that’s unsafe! You need to be wearing steel toed boots!” 😅
You have a lot more guts than I do! I'd never screw with a microwave producing transmitter like this!
Very few things scare me in this world but they are in order being high up, electricity, large compressed springs, very large mangets, deep water, dark open space
Reguarding differences in temp and differences in old and new ovens. i doubt the watts per liter is actually making a significant difference. My reasoning is that even though there is greater volume in the new, it simply means the microwave energy might bounce around more before being absorbed by the cup of water. I think the differences in power is likely more to do with the transformers as you pointed out. You could probably swap the transformers easily. At least temporarilly move the trabsforner to prevent saturating its core material.
I always thought my parents were exaggerating when they said "They don't build them like they used too".
I'm finally realizing that maybe our parents actually know what they are talking about.
At the old microwave you can "Skip" the timer if you setit to a long time and switch the microwave with an external power switch manually. So you get 1min runtime always.
Magnet deadlift, that's scary!
You need one of those magnetic films you can see the magnetic flux lines and see how it's impacting the microwave, the microwave might be working like a Faraday cage aswell
It’s a good thing he’s wearing slippery socks on very smooth surfaces while putting tons of energy into pulling magnets from metal while on a table! Nothing can go wrong there!
Cesium-infused mushrooms? Yum!
The way that magnet is compressing …. That is some grab!
The new microwave resetting is probably due to the small transformer for the timer saturating
Possible improvements:
Offset the glass on the rotating table from the center so that it can sweep thru hot and cold spots of radiation in the microwave
Turn on the old microwave and switch its power at the socket to get exactly 1 minute
New safety precaution: Don't watch whilst you eat, because you might choke on your food when laughing...
nothing as good as doing magnet experiments in socks
Been a subscriber of your channel for years and love your experiments. Where do you get strong neodymium magnets from please & how do you know what the various magnet codes mean? Best wishes from here in the UK.
would have been interesting to see if the ovens took the same amount of electrical power with the magnets applied.
You could use a stopwatch and switch it off at the mains to to get acurite timing over the dial timer.
wow I underestimated the amount of effort to take the big magnet off a large appliance.
I pushed my Radiacode 103 to its limit recently with an old Chirana X-ray tube. It maxed out at 1mSv/h with over 3 million CPM. If you’re wondering I have a remotely operated switch, so I don’t have to be anywhere near it when it’s running.
putting the magnet on the side with the transformer will just definitely smash the casing and probably cause a short somewhere, nevermind turning off the transformer :D
you forgot another warning on the beginning of the video that playing with your wife's microwave will get you punished.
We had a Kitchen Aid microwave that started misbehaving in a very weird way. Sometimes instead of heating food up, it bizarrely actually made the food colder. Can't wrap my head on how that is possible. You could always tell when it wasn't working properly as it made a different sound.
thats literally impossible my dude.
@@Basement-Science Maybe he accidentally discovered a new phenomenon.
@@Basement-Science Tell that to the food that got colder. The food was room temperature before putting it into the micro but ws colder when I took it out.
@@chuckthetekkie and you determined that how? And where was it colder? what even was it?
The monster magnet series is my favourite, perhaps Air-conditioner or Refrigerator?