I spent my career working with digital, now I’m jumping over to analogue for my midlife crisis. Coils... bugged the hell out of me because I just didn’t get them. After watching this video, I get it! Thank you for a very well explained and demonstrated video! 👍🏻
Inductors have been quite a mystery for me this far. Your excellent demonstrations helped a lot in understanding them better. This was likely the best practical intro to them I've seen. Keep up the great work, thanks!
Yes mate, a no nonsense, straight to the point, clearly described presentation bursting with facts in a perfectly digestible format.... This is a gold standard introduction to inductors and their properties. Perfect.
I recently started winding my own toroids for some low-power ham radio kits. It's worth mentioning that even on a high-end RF-rated toroid (e.g. type 43 ferrite) the proximity of turns can make a pretty big difference in the final inductance; if they're all bunched together, you get more inductance but lower efficiency, and if they're evenly spread out, the inductance is lower but the efficiency is higher. Not having a component tester, though, I had to come up with an alternate way to test inductances; the simplest way is to build a resonant circuit with a known-value (measured) capacitor and see what frequency it resonates at. With a decent oscilloscope, this should be a lot more accurate than a component tester.
One thing that you can also use for the winding of the inductor is "layered" enameled copper wire, it can handle more current at higher frequencies * layered enameled copper wire just means multiple enameled copper wires put side-by-side (aka in parallel) and then wrapped around the core; only electrically connected at the ends. Hope this helps!
Layers in an inductor are not paralleled wires. They are physical layers, one on top of another. This is important because the number of layers influences the AC losses in the winding due to proximity effect. Each layer _could_ be made of paralleled strands.
I've just started working on superconducting magnet coils as a technician. And asked the team leader about inductance, long story short your explanation is awesome.
Fantastic to see some real life practical examples of inductor usage. Inductors have always been a bit of a mystery to me. Love the analogy of a coiled spring.
Don’t need to overkill catch diodes. When sizing catch diodes, remember that current doesn’t increase with fly back. The inductor does what is needed to keep the previous current flowing briefly, however much voltage it takes to do that. So if your 70mA relay coil is switched off, it will continue to pass that 70mA briefly. A 1N4148 catch diode will handle that easily! And with your power inductor at 1A, a IN4001 will do the job just fine.
I work on refrigeration systems. We put vfds on the condenser motors a while back. They were blowing up motors left and right. Aside from the motors not being rated for vfds at the time (over a decade ago) they added these electric filters on the outputs of the vfds. I'm no electronics guy, but are those filters we added essentially just inductors for taking out the spikes like you mention in this video on the buck converters? The output of vfds are dc that mimic ac as far as I understand. Which isn't much.
Thank you. Very informational video. I am a complete rookie in electronics and I am just beginning to find the fun of this hobby. Thank you for your Lesson.
In RF parlance, especially in the amplifier arena, capacitors and inductors are labeled as tank blocking capacitors which pass RF current and block DC, while the plate chokes block RF current and pass DC, unless they're making up the tuned resonant tank circuit, where you want the cap to charge and discharge, and the inductor to ring, forming the flywheel effect in class B and C amplifiers. Another choke is used off the load capacitor to ground, which is for safety if the plate cap fails, connecting the HV to the tank. This, of course, blows the fuse before allowing HV into the antenna circuit. However, that choke's ringing causes HV to appear across the tuning and load cap's plates, and they have to be rated for that. In the plate power circuit of tube amps, the cap passes the anode's RF to the tank circuit while blocking HV DC, and the RF plate choke blocks the RF from entering the HV power supply. It's like using two types of check valves in a hydraulic circuit, and very similar to a diode's action.
Between the natural grown PCBs and the flyback "as a person" demonstration, you have earned my sub and like good sir. I don't often audibly laugh from youtube videos, let alone electronics related ones, but this one really got me. As a budding electronics enthusiast and (hopefully) future Electronics engineer, I hope to learn alot from this channel!
Looking at inductor's for antenna matching and came across this video. Very interesting especially about making them and the difference between the two with the same inductance. Tnx mate
You're very articulate...and make it nearly effortless for others grasp the content. I highly recommend your approach. You will make a great mathematics lecturer 👌
I would like to re-iterate a previous comment. You are so easy to understand and don't leave anything out. Which a lot of Electro tech tutors have a tendency of doing.
5:43: "Placing a diode backwards to the power source across the inductor/coil allows the flyback to flow back through the diode when power is disconnected from the inductor/coil." While the sentiment is correct, the description is not. Inductor voltage "flies back" as the result of a discontinuity of CURRENT, not "power." V = L*dI/dt, where dI/dt is theoretically infinite when the current suddenly is disconnected. Inductors will do all they can to prevent current discontinuity by the voltage suddenly flipping trying to find a place for the CURRENT to go to. That's what the diode does. No current can flow through the diode when it is biased off, but during this voltage flip, the diode is suddenly forward biased, giving the current a place to go. If you put a current probe on the diode, you would see current changing smoothly from its DC value, then ramp downward with a ramp shape that is I(t) = integral (Vdiode/L)*dt until the current goes to zero, and which point the inductor energy (1/2 * L*I^2) has been dissipated by the diode. You do a disservice to your viewers by interchanging current and power. They are completely different animals!
Fantastic display , after 30 yrs learning and still playing with automotive electronics, in my field opening up and repairing modules are not preformed any more , But I still open and find that trying to solve basic faults , which I’m successful, and surprisingly high rate of repairs work , are simple as understanding basic principles, post like the one you have shown are a excellent learning and teaching Aid , well done !!!!! Your excellent skill and passion are shown through your well explained and simplified teaching, very happy to subscribe and view all your post, Sadly my world of repair is mostly software and this greatly confuses a Tech as simple software fault can imitate a hard Eletricial issue / fault with a clients concern is brought to a dealer ship , Thus , weeding out a software fault from a ‘ hard ‘ Eletrical issue can be trying , but it is just a elimination path I take , Your post show very importantly the understanding and it’s fantastic that you’ve taken the time to do so , Thankyou and looking forward to seeing more post , keep it up ! :)
I built a 60 watt transistor stereo from Heath kit back in the day. I would bridge a 47 mf Disc capacitor across each speaker output To keep from hearing my neighbour talking on his CB radio through my speakers, It worked!
Very nice video. The simple explanation of how an inductor works by using examples of things that are far and away more complex than a simple inductor seems counterintuitive.
I had to pause to comment, "oh my god," as you smashed LED, resistor and cap, and I'm an atheist. You are a Kiwi treasure. I salute you with subscription, sir.
From the coil32 page......Another case is the inductor in the switching power supply. The commonly used ferrites have a relatively low value of saturation flux density (about 0.3 T), so in the power switching circuit the inductor is switched between the maximum value of the field when it almost gets a saturation and zero-field value, when it is demagnetized to a value of residual induction (curve [4]). As we can see the slope of the major axis of the ellipse 4 is much smaller than that of the ellipse 3. In other words, the magnetic permeability of the core in this mode is greatly reduced. The situation becomes worse if the choke core has DC bias (curve [5]). The major hysteresis loop of the real ferrite is more rectangular than on our schematic image and, in the end, the dynamic magnetic permeability of the power inductor on a ferrite ring falls to several units. As if there is no the ferrite! In the end, the inductive reactance of the inductor decreases, the current increases dramatically (which results in an even larger decrease in µ!), the key transistor heats up and burnout. The calculations of Coil32 for this choke give an absolutely wrong result. Because, we used to calculate the value of initial magnetic permeability, and in a real circuit, the permeability is two to three orders smaller. You will get the same situation if you will measure the relative permeability of the toroid by the trial winding. The solution is to use a ferrite core with the interrupted magnetic circuit. In the case of the ferrite ring, it is necessary to break it in half and then glue that two half with the non-magnetic gap. The major hysteresis loop of such a core becomes more sloping [2], the residual induction is much less [B'r], the effective magnetic permeability is also less than that of the core without a gap. However, the curve of magnetization [6] shows that the dynamic magnetic permeability of this inductor is much higher than that of similar, but with a core without a gap. It has permeability about 50..100. Coil32 also is unable to calculate this choke, since it does not take into account the non-magnetic gap. Another solution is the use of special rings for the power supply as powdered iron toroids (not ferrite). Such toroids can be found in pulse power supply units and motherboards of computers. The non-magnetic "gap" in such ring is distributed along its length. Conclusion. The Coil32 program calculates only low-current ferrite toroid coil working in low magnetic fields. For the power chokes calculation, it is necessary to use a completely different methodology.
I had the same comment that someone else made. With inductors, you increase the voltage, not the current. The maximum current is what you pass through the inductor while connected to the supply. When disconnected, the current decays, based on the resistance in the flyback circuit. The rate (aka speed of the decay) is related to the inductance/resistance time constant. The higher the resistance, the higher the voltage (and faster the decay). But again the current never exceeds the what it was passing at the instant before being disconnected. Without a flyback diode - the resistance is infinite - or whatever the rest of the connected circuit is, as parts begin to break down. A related phenomenon is that the high voltage can actually cause a spark, as the collapsing magnetic field attempts to maintain the current. When one unplugs a high inductive load - such as an iron or toaster - from the household mains, you will likely see a spark - that is the flyback voltage trying to dissipate the current.
- probably already in the comments somewhere, but I'm not going to read over 600 comments to find out: The peak current at turn-off of an inductor can *_never_* exceed the current at the instant turn-off starts. This is a fundamental property of inductance. If a relay coil operates at, say 100 mA, the current at the instant of turn-off will be 100 mA and decline from there. For small relays a 1N4148 or 1N914 or similar diode is entirely satisfactory. If the coil current exceeds half an amp then you might go to something rated at 1 amp. I've used dual transistors in surface mount packages for driving relays. One transistor is used as the switch and the other is used as a diode (collector-base; the base-emitter diode has some better properties for some applications but small reverse breakdown voltage, typ. 6 or 7 volts for common types). This makes things very compact. ~~~ That HY-2 inductor core is a Micrometals Type 52 powdered iron material, or a counterfeit thereof.
This is the best video of concepts of inductor. I really undestand when you make analogy with spring. The diference aboult capacitor and inductor is very interresting. Thank You!
Before watching this video, I had a basic understand of inductance, coils, magnetic fields, etc., but now after watching this video, I not only feel I finally understand inductance, but how it's used and dealt with! Thank you!!
Just a grammar tip to help polish the old image: Apostrophe S after a noun denotes possession. "Inductor's" implies there's something that belongs to said inductor. For plural, just drop the apostrophe. "Inductors". You also don't need to capitalize after the ampersand. Best of luck to you
Excellent explanation. I mainly deal with AC, but your clarification of DC circuits is massively helpful. Small point of contention though regarding definitions, an inductor I believe doesn't so much "resist" current so much as "impede" it. The definition and distinction I was taught is that resistance is work done that produces heat, whereas impedance doesn't. But then I guess no matter the length of copper wire you are using it will have some inherent resistance to it. Great video!
Love your presentation. I am glad that I am not the only one to notice the "black hole" in one's workshop that gobbles up all erratic kinetic objects never to be seen again. LOL. Like other commenters here, I have always been perplexed by inductors, but you make the concepts crystal clear. I guess the birds in NZ do not like PCB seeds which allows the PCBs to grow in the wild.
One important comment from an old winder: *Always* start winding the wire from the middle and wind both ends separately. This way you dont have to thread a long wire so many times. The total length of wire to thread is reduced by x4.
Excellent and extremely thorough presentation (technical content and instrument results) plus totally understandable physical speech and phraseology!!! Plus, plus, plus - no bloody annoying and distracting music!!! Previously subscribed to your site - cheers from Down Under.
A better analogy for the stored energy is the kinetic energy of a moving body, because inductors give inertia to electric current. Interruption of the circuit (creating a voltage spike) corresponds to collision of the moving body with an obstacle (exerting a high force for a short time). A compressed spring is an analogy for a charged capacitor. Movement created by the released spring corresponds to discharge current from a capacitor.
Those are the best mechanical analogs. Add a dashpot (shock absorber) as the mechanical analog for a resistor and you can visualize RLC circuits as masses, springs, and dashpots - or vice versa. One good example would be examining the response of a suspension sytem to a bump in the road. The tire/wheel would be the mass (inductor) connected to the spring (capacitor) and dashpot (resistor). The damped system can then be analyzed as an RLC circuit responding to a step input.
@@vicruzr wow😳 wonderful analogies. Please where can I get more of these analogies (any detailed basic e-book at all🙏 )for better understanding of circuits, bit by bit to complex level.
Beautifully explained. So electrically an indicator is like capacitor that has had its two parallel separate conductors shorted together at the end. And would become a capacitor again if "unshorted".
Great video and information, thank you very much! FYI, I haven't sanded or burned the insulation from this kind of wire for many years now. Modern coated wire is made to solder through, at least on all the wire I've dealt with. Just hold the soldering iron and solder on it for a few seconds and it works like magic, instantly tinned.
Magnet wire insulated with a nylon/polyester blend can be soldered without stripping. Lots of magnet wire cannot and has to be mechanically stripped or striped in a "salt pot" stripper at very high temperature. One of my clients, which made large iron core transformers in house, used an oxyacetylene torch. If you set the flame to oxidizing (more oxygen than needed for the acetylene) and put the wire in the oxidizing part of the flame, the insulation is cleanly stripped. You can't do this with something like a propane torch. It will simply burn the insulation leaving a mess that still has to be removed mechanically, though more easily than unburned insulation. I used to buy magnet wire from a supplier to motor rewinding shops. They didn't stock the stuff with solder-through insulation because it isn't robust enough for industrial motors.
This is interesting as I've tried building a switching PSU using a chip maker's application circuit diagram, but it doesn't work, and from various tests it looks like the chip's oscillator is running but there's no output from the main switching transistor, and it's a step down series regulator circuit, so it makes me wonder if I've used the wrong coil, it's the right inductance near enough, but possibly the wrong core material. Or could it be yet another circuit I've tried building where the design looks ok on paper but it's not been properly tested, and while that seems highly unlikely believe me I have known that to happen with other stuff I've tried building to someone else's design and I've had to alter it to get it to work. And the coil I tried using was a quite large toroidal one from a major supplier but it could still be unsuitable, but I'm not that familiar with switching supplies as they're far more technical than the more basic linear series regulator.
Automotive ignition systems use this principle to fire the spark plugs. In the old days they used mechanical points along with an ignition coil to open and close the circuit.
At 15:32 in the video, we are told that "inductors basically have no effect on DC power". Why does my Drok DC to DC step down voltage regulator have an inductor?
As he said in the video, " In the case of buck converters and switch mode power supplies, inductors are used to help smooth out the voltage ripple caused by the high switching frequency." If chosen properly, the inductor is invisible to the DC produced, but it can greatly reduce the amount AC noise that makes it to the output.
@@sincerelyyours7538 I am still a bit confused but what's new! You mentioned "greatly reducing the amount of AC noise". As I had written, my "Drok" is the DC to DC type. The input is connected to a 12Volt battery as opposed to a wall outlet and the output is dialed down to 6Volts DC to power a portable Short Wave radio. So given your response, I guess my new question is... Is AC somehow being created during the DC to DC voltage reduction process?
@@tribulationprepper787 Yes, definitely. According to Wikipedia, "Switched-mode DC-to-DC converters convert one DC voltage level to another, which may be higher or lower, by storing the input energy temporarily and then releasing that energy to the output at a different voltage. The storage may be in either magnetic field storage components (inductors, transformers) or electric field storage components (capacitors)." They work by chopping the input energy using a high frequency switching circuit and then adjusting the duty cycle to regulate the output voltage to the desired level. That voltage is then rectified and regulated into DC again, but at a different level than where the input was. The idea here is to avoid using a large transformer, a la linear power supplies, which are heavy, costly, inefficient and take up too much space. By using a frequency considerably higher than the 50 or 60 Hz coming out of your wall you can get away with using a much smaller transformer, or even no transformer in the case of small IC driven DC to DC converters like yours, and let the ICs and MOSFETS do all the work. The downside is that they produce lots of switching noise which then must then be filtered to keep it from getting into frequency sensitive appliances like computers and radios.
@@sincerelyyours7538 Thank you so much for your research. I am thankful that my little Drok device is capable of preforming it's intended duty without a need for five extra pounds of wound, enameled copper wire. I have to hand it to the engineers that figured out how to design and build so much capability into such a small package. It is a borderline miracle for sure. Pure electronic genius! Again, thank you.
After inductance, the next most important property of inductors is it's saturation current. Basically when inductor reaches saturation current its inductances decreases to almost zero. This is the probable reason those inductors presented different results.
Using the diode in parallel with the relay coil slows down the release of the contacts. If the contacts carry some considerable current, you mau get an arc that damages the contacts. Most of the time I make a compromise between the kick-back voltage and the speed by adding some resistance (up to the same as the relay coil resistance is) in series with the diode. By the way, the relay coil also presents at the release time to the diode loop energy stored in the spring that opens the contacts.
A good way to speed up the release is to wire up a bidirectional tvs diode rated to a voltage your switch will withstand, in parallel to the relay coil. Most of the time, you'll be using mosfets to control relays, and mosfets will have that tvs diode "built-in", so to say. Look for "avalanche current" spec in the datasheet: if it is greater than the current consumed by the relay, you don't need to add anything, the mosfet will safely absorb the energy stored by the coil, and dissipate it as heat.
@@victortitov1740 Fine as far as it goes. I am uneasy about, say 24 V relay producing a maybe 300 V kick corresponding to a likely FET avalanche rating. A list of different "safe" voltages has several confusing numbers, of which I have derived 48 V as my favorite (just below the 50 V list value).
I have that very same component tester. It doesn't work too bad. The LCD screen lost its seal on mine shortly after I bought it, but still works. Every once in awhile it will give some erratic readings. I bought mine and assembled it. I had to come up with my own case for it.
oh boy, where do i start... "inductors can't store energy when disconnected from power supply" - no, they can. Ideal inductor will store its energy indefinitely if it is shorted. Real inductors rarely achieve more than a second of useful storage time. This is unlike capacitors primarily because our insulators are much closer to ideal than our conductors. Like capacitor requires ideal insulator (zero leakage) to store energy indefinitely, inductor requires conductor with no resistance (superconductor) to store its energy indefinitely. spring analogy - see other comments... the analogy is acceptable, but there is a better analogy with mass hitting a brickwall. "if flyback were a person" - oh dear... diode peak current 220 amps "massive overkill" - it is indeed massive overkill. The peak current that will flow through the diode is equal (slightly less, actually) to the current that was flowing through the coil just before breaking the circuit. This is exactly the rule "inductor resists a change in current". It will slowly decay afterwards. There is no need to account for more. Heating may be of concern if the load is cycled on and off fast. "Inductors help smooth out voltage ripple caused by high switching frequency" yes they can, but their primary use in switchmode converters is very different. They are temporary energy storage that can be filled using one voltage (the input voltage) and drained at another voltage (usually but not always, the output voltage). They are at the very heart of the conversion process (with some exceptions). "these spikes are undesired voltage ripple" - no. These are conducted emissions (mostly caused by parasitic inductances, capacitances and transformers in your circuit), they are not called "voltage ripple". Voltage ripple is usually the changes in capacitor voltage that happen as the inductor enegry is dumped into it, and then capacitor is discharged by the load. The ripple usually looks like sawtooth with a bit of square wave, but it can take very weird and wonderful shapes due to complex behavior of capacitors and inductors, feedback problems, burst mode operation of some converters, and lots of other intricacies. On your pictures, true voltage ripple is clearly visible only under load (but you measure peak-to-peak value which is dominated by these conducted-emission spikes). "the buck converter got very hot" and you have not explained why. You have removed the fundamental piece of it, effectively shorting out the switching node of the ic. The IC is always in overload protection, and i'm actually surprised it didn't die right away. This is why it got hot. "" - you don't explain, why so. What properties of these materials are the reason for their intended application. I tell ya. It is the energy that can be stored in the core before core is saturated. Power applications require that energy storage. Signal filtering and transformer applications don't. You can actually make a pretty decent power inductor from a high-permeability core by introducing an air gap (effectively reducing its permeability; the energy is then actually mostly stored in the gap, not in the core). "1mm copper wire which is suitable for the current" - waaay too simplified. There are two current ratings for an inductor: the current at which its core saturates (where it mostly turns into a resistor), and the current at which it overheats. They are not equal. The saturation rating is insensitive to wire thickness. In practice, inductors are usually picked so that the peak current never exceeds saturation rating, and rms current never exceeds overheating rating, although there is more to it (core loss can cause additional heating). 1mm may be suitable or may be not, there is no simple answer. "you may have to use a larger toroid because the wire will not fit" - yes and no. The core must be able to hold the energy the converter requires. That's the minimum. Then you may indeed be unable to fit enough wire and that will indeed force you to pick a bigger core. "" - that's a very simplistic calculator that is not suitable for designing power inductors, because current rating is extremely important, and that calculator gives you no clue. Peculiarly, the calculator has wire thickness. The thickness mostly doesn't affect the inductance, so i wonder what is it there for. For estimating the needed length is my guess... ==final message== "inductors have no effect on dc power" - sorta true. "inductors only affect ac power" = same as above "ac power === ripple" - yes but not quite. Every ripple is "AC", but not every AC is ripple. "AC" in quotemarks because ripple superimposed on DC is usually not enough to make it truly alternating. "inductors don't affect voltage" - just nonsense. "inductor resists sudden changes in current flow" - true. "which in turn can smooth out unwanted voltage ripple" - true, but that's not their main use in switching converters.
Olá !!! amigo sabe me explicar por que a limalha de metal não grudou em toda a extensão da bobina ficou presa ( grudou ) apenas no canto esquerdo ??? em 2:24
Thanks keep it up i wish if you could explain in depth how many turns of an inductor or of a wire around a reed switch is needed to turn it on or if you could recommend a website or a calculator to do such task
How can i build something like that inductor tester? Am so much at the right place. This is the best ever tutorial after i wasted my two years on other channel to keep on feeling like quiting electronics.
I love your JLPCB ad, but more than that, I watched your hammer smashing section twice, and laughed out loud both times! I'm laughing now, just thinking about it :)
I’m quite new to electronics, so my use of a 12v relay is limited. I plan to have an Arduino controlling a few 12v lights with a relay board designed specifically for Arduino. Would I need to worry about any kind of voltage spikes if I isolate the 12v circuit from the 5v of the micro controller? I was under the impression that relays were safe but now I’m unsure 😅
@Fred Garvin So how do you get a higher output voltage then? As far as I know it occurs when you cut the supply to the inductor, causing its field to collapse and it generates a back emf. The duty cycle is to regulate the output voltage and with higher switching frequencies you can get higher voltages from smaller inductors because faster current disruptions cause higher back emfs.
THIS IS the best JLPCB advertisement among all JLPCB advertisements :)
You forgot the first C in JLCPCB.
Too Bad he didn't clip them to the the tree branches, too.
I first thot he'd get shocked by the electric barbed wire fence.
Whew, Lad!
Came to comments just to say this or see someone else saying this… and… well, I am not disappointed… first comment 🤘
@@user-mp3eq6ir5b same, I was like… is it going to zap him? I was confused why he was going out there dressed like that 😂
*MARKETING*
Man, you're a legend, wish I had professors half as interesting and clear in expression as you are.
th-cam.com/video/aY8ONv6_a7I/w-d-xo.html&feature=share
My courses were all math with a rare lab---too bad I did not have you Dr. Schematix!!! Hands on is the only way to learn.
He must’ve flunked English. There’s no apostrophe in the plural word “inductors”.
Pravda!
@@outerrealm It's OK, he is smart as hell when it comes to inductors.
I've watched so many inductor tutorial videos and I swear none of them were even close to being as informational as this one. Thank you.
I spent my career working with digital, now I’m jumping over to analogue for my midlife crisis. Coils... bugged the hell out of me because I just didn’t get them. After watching this video, I get it!
Thank you for a very well explained and demonstrated video! 👍🏻
Inductors have been quite a mystery for me this far. Your excellent demonstrations helped a lot in understanding them better. This was likely the best practical intro to them I've seen. Keep up the great work, thanks!
i still dont get what theyre used for tbh
@@PinkeySuavo Me neither.
Yes mate, a no nonsense, straight to the point, clearly described presentation bursting with facts in a perfectly digestible format....
This is a gold standard introduction to inductors and their properties.
Perfect.
I recently started winding my own toroids for some low-power ham radio kits. It's worth mentioning that even on a high-end RF-rated toroid (e.g. type 43 ferrite) the proximity of turns can make a pretty big difference in the final inductance; if they're all bunched together, you get more inductance but lower efficiency, and if they're evenly spread out, the inductance is lower but the efficiency is higher.
Not having a component tester, though, I had to come up with an alternate way to test inductances; the simplest way is to build a resonant circuit with a known-value (measured) capacitor and see what frequency it resonates at. With a decent oscilloscope, this should be a lot more accurate than a component tester.
I have done that.
The tolerance on the Capacitor and the accuracy of the frequency counter or Oscilloscope sets the tolerance of your final answer.
One thing that you can also use for the winding of the inductor is "layered" enameled copper wire, it can handle more current at higher frequencies
* layered enameled copper wire just means multiple enameled copper wires put side-by-side (aka in parallel) and then wrapped around the core; only electrically connected at the ends.
Hope this helps!
Layers in an inductor are not paralleled wires. They are physical layers, one on top of another. This is important because the number of layers influences the AC losses in the winding due to proximity effect. Each layer _could_ be made of paralleled strands.
Loved that "if flyback were a person" thing. I wish I had a physics teacher like you 🙏 🤓👨
I've just started working on superconducting magnet coils as a technician. And asked the team leader about inductance, long story short your explanation is awesome.
Fantastic to see some real life practical examples of inductor usage. Inductors have always been a bit of a mystery to me. Love the analogy of a coiled spring.
Hello thanks very much for teaching I have learnt something new looking a head to more videos like this
One of the best videos I have ever watched on youtube!
Thank you for sharing your knowledge so effectively xD
Excellent explanation of theory and good examples.
Don’t need to overkill catch diodes. When sizing catch diodes, remember that current doesn’t increase with fly back. The inductor does what is needed to keep the previous current flowing briefly, however much voltage it takes to do that. So if your 70mA relay coil is switched off, it will continue to pass that 70mA briefly. A 1N4148 catch diode will handle that easily! And with your power inductor at 1A, a IN4001 will do the job just fine.
I work on refrigeration systems. We put vfds on the condenser motors a while back. They were blowing up motors left and right. Aside from the motors not being rated for vfds at the time (over a decade ago) they added these electric filters on the outputs of the vfds. I'm no electronics guy, but are those filters we added essentially just inductors for taking out the spikes like you mention in this video on the buck converters? The output of vfds are dc that mimic ac as far as I understand. Which isn't much.
That flyback person demo is awesome. Well done video. Thanks!
Nice theoretical and practical demonstration. In the same manner I would like to have a look at chokes!
Thank you. Very informational video. I am a complete rookie in electronics and I am just beginning to find the fun of this hobby. Thank you for your Lesson.
This is the best video tutorial on Inductors I have seen thus far. Much appreciated, thanks.
In RF parlance, especially in the amplifier arena, capacitors and inductors are labeled as tank blocking capacitors which pass RF current and block DC, while the plate chokes block RF current and pass DC, unless they're making up the tuned resonant tank circuit, where you want the cap to charge and discharge, and the inductor to ring, forming the flywheel effect in class B and C amplifiers. Another choke is used off the load capacitor to ground, which is for safety if the plate cap fails, connecting the HV to the tank. This, of course, blows the fuse before allowing HV into the antenna circuit.
However, that choke's ringing causes HV to appear across the tuning and load cap's plates, and they have to be rated for that.
In the plate power circuit of tube amps, the cap passes the anode's RF to the tank circuit while blocking HV DC, and the RF plate choke blocks the RF from entering the HV power supply. It's like using two types of check valves in a hydraulic circuit, and very similar to a diode's action.
These ads are actually great. Most TH-camrs make the ad spots boring af, but these are hilarious
the best inductor/inductance explanation since my days of electrical engineering at Tulane.
When people.say they don't trust youtube to find knowledge.
@@bringer-of-changeThis too is part of the Scam, to justify and exonerate the role of the Bogus, rigged Education system.
69likes🌚
Lol
Between the natural grown PCBs and the flyback "as a person" demonstration, you have earned my sub and like good sir. I don't often audibly laugh from youtube videos, let alone electronics related ones, but this one really got me. As a budding electronics enthusiast and (hopefully) future Electronics engineer, I hope to learn alot from this channel!
you just killed me over here with the god dammed spring bouncing all over the place LOL good one.
Very informing!! I am in the process of learning more and indulging in projects involving inductors
Looking at inductor's for antenna matching and came across this video. Very interesting especially about making them and the difference between the two with the same inductance. Tnx mate
You're very articulate...and make it nearly effortless for others grasp the content. I highly recommend your approach. You will make a great mathematics lecturer 👌
Best video about electromagnetics I've seen so far
I would like to re-iterate a previous comment. You are so easy to understand and don't leave anything out. Which a lot of Electro tech tutors have a tendency of doing.
Best possible explanation of inductors I have ever came across.
Very nice explanation... I listened to this multiple times. Thanks a lot.
This is by far the best sponsor acknowledgement I have ever seen :D
5:43: "Placing a diode backwards to the power source across the inductor/coil allows the flyback to flow back through the diode when power is disconnected from the inductor/coil." While the sentiment is correct, the description is not. Inductor voltage "flies back" as the result of a discontinuity of CURRENT, not "power." V = L*dI/dt, where dI/dt is theoretically infinite when the current suddenly is disconnected. Inductors will do all they can to prevent current discontinuity by the voltage suddenly flipping trying to find a place for the CURRENT to go to. That's what the diode does. No current can flow through the diode when it is biased off, but during this voltage flip, the diode is suddenly forward biased, giving the current a place to go. If you put a current probe on the diode, you would see current changing smoothly from its DC value, then ramp downward with a ramp shape that is I(t) = integral (Vdiode/L)*dt until the current goes to zero, and which point the inductor energy (1/2 * L*I^2) has been dissipated by the diode. You do a disservice to your viewers by interchanging current and power. They are completely different animals!
Fantastic display , after 30 yrs learning and still playing with automotive electronics, in my field opening up and repairing modules are not preformed any more ,
But I still open and find that trying to solve basic faults , which I’m successful, and surprisingly high rate of repairs work ,
are simple as understanding basic principles, post like the one you have shown are a excellent learning and teaching Aid , well done !!!!!
Your excellent skill and passion are shown through your well explained and simplified teaching, very happy to subscribe and view all your post,
Sadly my world of repair is mostly software and this greatly confuses a Tech as simple software fault can imitate a hard Eletricial issue / fault with a clients concern is brought to a dealer ship ,
Thus , weeding out a software fault from a ‘ hard ‘ Eletrical issue can be trying , but it is just a elimination path I take ,
Your post show very importantly the understanding and it’s fantastic that you’ve taken the time to do so , Thankyou and looking forward to seeing more post , keep it up ! :)
Finally I got proper knowledge about inductor and it's used nice video 👏👏 thoroughly practical enjoyed your video Thanks 👍😍
I built a 60 watt transistor stereo from Heath kit back in the day. I would bridge a 47 mf Disc capacitor across each speaker output To keep from hearing my neighbour talking on his CB radio through my speakers, It worked!
Very nice video. The simple explanation of how an inductor works by using examples of things that are far and away more complex than a simple inductor seems counterintuitive.
I had to pause to comment, "oh my god," as you smashed LED, resistor and cap, and I'm an atheist. You are a Kiwi treasure. I salute you with subscription, sir.
EXCELLENT INFORMATION.
Very good Presentation.
Thanks A LOT.
Awesome ! I’m building a voltage current sensor for I2c bus 😅 .300 mA 😮 all going to be part of my oscilloscope / logic analyzer build
Teach me how to do that brother
The PCBs growing in the forest like mushrooms were great
Glad you enjoyed it. I try to keep my sponsorship segments entertaining & fresh :)
Copied from Marco Reps :-(
@@gustinian Nah. Marco Reps can only harvest capacitors where he lives, PCB's don't grow in that climate
Wait you guys find components in your forests my forests only grow meth labs and tires
@@thomastruant8837 Indiana?
Your video & Demonstration has relief me from some misunderstanding the nature of inductor. Thanks for the video.
From the coil32 page......Another case is the inductor in the switching power supply. The commonly used ferrites have a relatively low value of saturation flux density (about 0.3 T), so in the power switching circuit the inductor is switched between the maximum value of the field when it almost gets a saturation and zero-field value, when it is demagnetized to a value of residual induction (curve [4]). As we can see the slope of the major axis of the ellipse 4 is much smaller than that of the ellipse 3. In other words, the magnetic permeability of the core in this mode is greatly reduced. The situation becomes worse if the choke core has DC bias (curve [5]). The major hysteresis loop of the real ferrite is more rectangular than on our schematic image and, in the end, the dynamic magnetic permeability of the power inductor on a ferrite ring falls to several units. As if there is no the ferrite! In the end, the inductive reactance of the inductor decreases, the current increases dramatically (which results in an even larger decrease in µ!), the key transistor heats up and burnout. The calculations of Coil32 for this choke give an absolutely wrong result. Because, we used to calculate the value of initial magnetic permeability, and in a real circuit, the permeability is two to three orders smaller. You will get the same situation if you will measure the relative permeability of the toroid by the trial winding.
The solution is to use a ferrite core with the interrupted magnetic circuit. In the case of the ferrite ring, it is necessary to break it in half and then glue that two half with the non-magnetic gap. The major hysteresis loop of such a core becomes more sloping [2], the residual induction is much less [B'r], the effective magnetic permeability is also less than that of the core without a gap. However, the curve of magnetization [6] shows that the dynamic magnetic permeability of this inductor is much higher than that of similar, but with a core without a gap. It has permeability about 50..100. Coil32 also is unable to calculate this choke, since it does not take into account the non-magnetic gap. Another solution is the use of special rings for the power supply as powdered iron toroids (not ferrite). Such toroids can be found in pulse power supply units and motherboards of computers. The non-magnetic "gap" in such ring is distributed along its length.
Conclusion. The Coil32 program calculates only low-current ferrite toroid coil working in low magnetic fields. For the power chokes calculation, it is necessary to use a completely different methodology.
Omg that spring reference changed everything for me! Subscribed mate 🤙🏻
But it's not like a spring in that the current in the inductor doesn't change direction when it collapses.
THAT PCB INTRO WAS GENIUS!!!!
I had the same comment that someone else made. With inductors, you increase the voltage, not the current. The maximum current is what you pass through the inductor while connected to the supply. When disconnected, the current decays, based on the resistance in the flyback circuit. The rate (aka speed of the decay) is related to the inductance/resistance time constant. The higher the resistance, the higher the voltage (and faster the decay). But again the current never exceeds the what it was passing at the instant before being disconnected. Without a flyback diode - the resistance is infinite - or whatever the rest of the connected circuit is, as parts begin to break down. A related phenomenon is that the high voltage can actually cause a spark, as the collapsing magnetic field attempts to maintain the current. When one unplugs a high inductive load - such as an iron or toaster - from the household mains, you will likely see a spark - that is the flyback voltage trying to dissipate the current.
As someone who's fried a few boards early on in my days of home building CnCs, this a huge resource.
I studied this at university in New brunswick. The prof who taught the subject was very good explainer. so this video.
The best inductor video on TH-cam!!!
*Finally, an inductor tutorial that makes sense* 👍👍👍👍👍
That was such a clear and concise description and explanation as well as providing many useful pointers. Thanks.
this is my first time watching your channel, and man, you didn't hold anything back with picking wild PCBs, that was fantastic!
- probably already in the comments somewhere, but I'm not going to read over 600 comments to find out:
The peak current at turn-off of an inductor can *_never_* exceed the current at the instant turn-off starts. This is a fundamental property of inductance. If a relay coil operates at, say 100 mA, the current at the instant of turn-off will be 100 mA and decline from there.
For small relays a 1N4148 or 1N914 or similar diode is entirely satisfactory. If the coil current exceeds half an amp then you might go to something rated at 1 amp. I've used dual transistors in surface mount packages for driving relays. One transistor is used as the switch and the other is used as a diode (collector-base; the base-emitter diode has some better properties for some applications but small reverse breakdown voltage, typ. 6 or 7 volts for common types). This makes things very compact.
~~~
That HY-2 inductor core is a Micrometals Type 52 powdered iron material, or a counterfeit thereof.
Best explanation of inductor Thank you very much.
thank you, a very good tutorial on inductors
mike
This is the best video of concepts of inductor. I really undestand when you make analogy with spring. The diference aboult capacitor and inductor is very interresting. Thank You!
I am a starter mechatronic and stuff like this is really helpfull...not every proffessor explains stuff like this...love your content!
Nice video! I especially love the JLCPCB advertisement. I also love how you showed how flyback would be if it was a person.
JLCPCB needs to pay this man more
Your examples of flyback at 5:15 and 5:30 are... absolutely perfect 😎❤👍
Before watching this video, I had a basic understand of inductance, coils, magnetic fields, etc., but now after watching this video, I not only feel I finally understand inductance, but how it's used and dealt with! Thank you!!
Just a grammar tip to help polish the old image: Apostrophe S after a noun denotes possession. "Inductor's" implies there's something that belongs to said inductor. For plural, just drop the apostrophe. "Inductors". You also don't need to capitalize after the ampersand.
Best of luck to you
Excellent explanation. I mainly deal with AC, but your clarification of DC circuits is massively helpful. Small point of contention though regarding definitions, an inductor I believe doesn't so much "resist" current so much as "impede" it. The definition and distinction I was taught is that resistance is work done that produces heat, whereas impedance doesn't. But then I guess no matter the length of copper wire you are using it will have some inherent resistance to it.
Great video!
impedance includes resistance. are you thinking of reactance?
@@dotanuki3371 Yes, both are included in the term impedance, but inductive reactance is not the same as resistance.
Best inductor video on TH-cam! Thanks!
Love your presentation. I am glad that I am not the only one to notice the "black hole" in one's workshop that gobbles up all erratic kinetic objects never to be seen again. LOL. Like other commenters here, I have always been perplexed by inductors, but you make the concepts crystal clear. I guess the birds in NZ do not like PCB seeds which allows the PCBs to grow in the wild.
One important comment from an old winder: *Always* start winding the wire from the middle and wind both ends separately. This way you dont have to thread a long wire so many times. The total length of wire to thread is reduced by x4.
Wasn't even searching for this topic but I'm glad I found it, super interesting 👌
This helped me with inductors more than any other video I've seen. Thank you!
very clear and educational video. subscribed
Excellent and extremely thorough presentation (technical content and instrument results) plus totally understandable physical speech and phraseology!!! Plus, plus, plus - no bloody annoying and distracting music!!! Previously subscribed to your site - cheers from Down Under.
Awesome - Awesome-Awesome-Awesome-Awesome--
I do like your Method in teaching
Very good Intro to inductors! Best in helping visualize Flyback effect! Thanks!
Thanks!
A better analogy for the stored energy is the kinetic energy of a moving body, because inductors give inertia to electric current. Interruption of the circuit (creating a voltage spike) corresponds to collision of the moving body with an obstacle (exerting a high force for a short time). A compressed spring is an analogy for a charged capacitor. Movement created by the released spring corresponds to discharge current from a capacitor.
Those are the best mechanical analogs. Add a dashpot (shock absorber) as the mechanical analog for a resistor and you can visualize RLC circuits as masses, springs, and dashpots - or vice versa. One good example would be examining the response of a suspension sytem to a bump in the road. The tire/wheel would be the mass (inductor) connected to the spring (capacitor) and dashpot (resistor). The damped system can then be analyzed as an RLC circuit responding to a step input.
@@vicruzr wow😳 wonderful analogies. Please where can I get more of these analogies (any detailed basic e-book at all🙏 )for better understanding of circuits, bit by bit to complex level.
Beautifully explained.
So electrically an indicator is like capacitor that has had its two parallel separate conductors shorted together at the end.
And would become a capacitor again if "unshorted".
Thank you for concrete simple and clear teaching on inductor.
Great video and information, thank you very much! FYI, I haven't sanded or burned the insulation from this kind of wire for many years now. Modern coated wire is made to solder through, at least on all the wire I've dealt with. Just hold the soldering iron and solder on it for a few seconds and it works like magic, instantly tinned.
Magnet wire insulated with a nylon/polyester blend can be soldered without stripping. Lots of magnet wire cannot and has to be mechanically stripped or striped in a "salt pot" stripper at very high temperature.
One of my clients, which made large iron core transformers in house, used an oxyacetylene torch. If you set the flame to oxidizing (more oxygen than needed for the acetylene) and put the wire in the oxidizing part of the flame, the insulation is cleanly stripped. You can't do this with something like a propane torch. It will simply burn the insulation leaving a mess that still has to be removed mechanically, though more easily than unburned insulation.
I used to buy magnet wire from a supplier to motor rewinding shops. They didn't stock the stuff with solder-through insulation because it isn't robust enough for industrial motors.
Ok that ad was great. Got me.
This is interesting as I've tried building a switching PSU using a chip maker's application circuit diagram, but it doesn't work, and from various tests it looks like the chip's oscillator is running but there's no output from the main switching transistor, and it's a step down series regulator circuit, so it makes me wonder if I've used the wrong coil, it's the right inductance near enough, but possibly the wrong core material. Or could it be yet another circuit I've tried building where the design looks ok on paper but it's not been properly tested, and while that seems highly unlikely believe me I have known that to happen with other stuff I've tried building to someone else's design and I've had to alter it to get it to work. And the coil I tried using was a quite large toroidal one from a major supplier but it could still be unsuitable, but I'm not that familiar with switching supplies as they're far more technical than the more basic linear series regulator.
Interesting for sure. Nice to see the factual results with the scope, between the different inductors. Thumbs Up!
Automotive ignition systems use this principle to fire the spark plugs. In the old days they used mechanical points along with an ignition coil to open and close the circuit.
At 15:32 in the video, we are told that "inductors basically have no effect on DC power". Why does my Drok DC to DC step down voltage regulator have an inductor?
As he said in the video, " In the case of buck converters and switch mode power supplies, inductors are used to help smooth out the voltage ripple caused by the high switching frequency." If chosen properly, the inductor is invisible to the DC produced, but it can greatly reduce the amount AC noise that makes it to the output.
@@sincerelyyours7538 I am still a bit confused but what's new!
You mentioned "greatly reducing the amount of AC noise". As I had written, my "Drok" is the DC to DC type. The input is connected to a 12Volt battery as opposed to a wall outlet and the output is dialed down to 6Volts DC to power a portable Short Wave radio.
So given your response, I guess my new question is... Is AC somehow being created during the DC to DC voltage reduction process?
@@tribulationprepper787 Yes, definitely. According to Wikipedia, "Switched-mode DC-to-DC converters convert one DC voltage level to another, which may be higher or lower, by storing the input energy temporarily and then releasing that energy to the output at a different voltage. The storage may be in either magnetic field storage components (inductors, transformers) or electric field storage components (capacitors)." They work by chopping the input energy using a high frequency switching circuit and then adjusting the duty cycle to regulate the output voltage to the desired level. That voltage is then rectified and regulated into DC again, but at a different level than where the input was. The idea here is to avoid using a large transformer, a la linear power supplies, which are heavy, costly, inefficient and take up too much space. By using a frequency considerably higher than the 50 or 60 Hz coming out of your wall you can get away with using a much smaller transformer, or even no transformer in the case of small IC driven DC to DC converters like yours, and let the ICs and MOSFETS do all the work. The downside is that they produce lots of switching noise which then must then be filtered to keep it from getting into frequency sensitive appliances like computers and radios.
@@sincerelyyours7538 Thank you so much for your research. I am thankful that my little Drok device is capable of preforming it's intended duty without a need for five extra pounds of wound, enameled copper wire.
I have to hand it to the engineers that figured out how to design and build so much capability into such a small package. It is a borderline miracle for sure. Pure electronic genius!
Again, thank you.
Awesome... waiting for next inductor video that it can cause issue in circuit with practical and theoretical explanation...
Awesome video mate, look forward to seeing the kit available
Thanks mate! ;)
@@Schematix i see that some car relay have a resistor cnnext with the inductor on parallel and thanks
After inductance, the next most important property of inductors is it's saturation current.
Basically when inductor reaches saturation current its inductances decreases to almost zero.
This is the probable reason those inductors presented different results.
Does that mean its resistance drops as well? At the same time it reaches above saturation
Using the diode in parallel with the relay coil slows down the release of the contacts. If the contacts carry some considerable current, you mau get an arc that damages the contacts. Most of the time I make a compromise between the kick-back voltage and the speed by adding some resistance (up to the same as the relay coil resistance is) in series with the diode.
By the way, the relay coil also presents at the release time to the diode loop energy stored in the spring that opens the contacts.
A good way to speed up the release is to wire up a bidirectional tvs diode rated to a voltage your switch will withstand, in parallel to the relay coil. Most of the time, you'll be using mosfets to control relays, and mosfets will have that tvs diode "built-in", so to say. Look for "avalanche current" spec in the datasheet: if it is greater than the current consumed by the relay, you don't need to add anything, the mosfet will safely absorb the energy stored by the coil, and dissipate it as heat.
@@victortitov1740 Fine as far as it goes. I am uneasy about, say 24 V relay producing a maybe 300 V kick corresponding to a likely FET avalanche rating. A list of different "safe" voltages has several confusing numbers, of which I have derived 48 V as my favorite (just below the 50 V list value).
Regarding 1N4001 diode at 6:50: fast recovery or Schottky diode is the right type for that application.
This video is of high educational value and was a pleasure to watch. I came away knowing things I didn't know I wanted to know!
I have that very same component tester. It doesn't work too bad. The LCD screen lost its seal on mine shortly after I bought it, but still works. Every once in awhile it will give some erratic readings.
I bought mine and assembled it. I had to come up with my own case for it.
Gotta love your Widlariser at 5:30. 👍
oh boy, where do i start...
"inductors can't store energy when disconnected from power supply" - no, they can. Ideal inductor will store its energy indefinitely if it is shorted. Real inductors rarely achieve more than a second of useful storage time. This is unlike capacitors primarily because our insulators are much closer to ideal than our conductors. Like capacitor requires ideal insulator (zero leakage) to store energy indefinitely, inductor requires conductor with no resistance (superconductor) to store its energy indefinitely.
spring analogy - see other comments... the analogy is acceptable, but there is a better analogy with mass hitting a brickwall.
"if flyback were a person" - oh dear...
diode peak current 220 amps "massive overkill" - it is indeed massive overkill. The peak current that will flow through the diode is equal (slightly less, actually) to the current that was flowing through the coil just before breaking the circuit. This is exactly the rule "inductor resists a change in current". It will slowly decay afterwards. There is no need to account for more. Heating may be of concern if the load is cycled on and off fast.
"Inductors help smooth out voltage ripple caused by high switching frequency" yes they can, but their primary use in switchmode converters is very different. They are temporary energy storage that can be filled using one voltage (the input voltage) and drained at another voltage (usually but not always, the output voltage). They are at the very heart of the conversion process (with some exceptions).
"these spikes are undesired voltage ripple" - no. These are conducted emissions (mostly caused by parasitic inductances, capacitances and transformers in your circuit), they are not called "voltage ripple". Voltage ripple is usually the changes in capacitor voltage that happen as the inductor enegry is dumped into it, and then capacitor is discharged by the load. The ripple usually looks like sawtooth with a bit of square wave, but it can take very weird and wonderful shapes due to complex behavior of capacitors and inductors, feedback problems, burst mode operation of some converters, and lots of other intricacies.
On your pictures, true voltage ripple is clearly visible only under load (but you measure peak-to-peak value which is dominated by these conducted-emission spikes).
"the buck converter got very hot" and you have not explained why. You have removed the fundamental piece of it, effectively shorting out the switching node of the ic. The IC is always in overload protection, and i'm actually surprised it didn't die right away. This is why it got hot.
"" - you don't explain, why so. What properties of these materials are the reason for their intended application.
I tell ya. It is the energy that can be stored in the core before core is saturated. Power applications require that energy storage. Signal filtering and transformer applications don't.
You can actually make a pretty decent power inductor from a high-permeability core by introducing an air gap (effectively reducing its permeability; the energy is then actually mostly stored in the gap, not in the core).
"1mm copper wire which is suitable for the current" - waaay too simplified. There are two current ratings for an inductor: the current at which its core saturates (where it mostly turns into a resistor), and the current at which it overheats. They are not equal. The saturation rating is insensitive to wire thickness. In practice, inductors are usually picked so that the peak current never exceeds saturation rating, and rms current never exceeds overheating rating, although there is more to it (core loss can cause additional heating). 1mm may be suitable or may be not, there is no simple answer.
"you may have to use a larger toroid because the wire will not fit" - yes and no. The core must be able to hold the energy the converter requires. That's the minimum. Then you may indeed be unable to fit enough wire and that will indeed force you to pick a bigger core.
"" - that's a very simplistic calculator that is not suitable for designing power inductors, because current rating is extremely important, and that calculator gives you no clue.
Peculiarly, the calculator has wire thickness. The thickness mostly doesn't affect the inductance, so i wonder what is it there for. For estimating the needed length is my guess...
==final message==
"inductors have no effect on dc power" - sorta true.
"inductors only affect ac power" = same as above
"ac power === ripple" - yes but not quite. Every ripple is "AC", but not every AC is ripple. "AC" in quotemarks because ripple superimposed on DC is usually not enough to make it truly alternating.
"inductors don't affect voltage" - just nonsense.
"inductor resists sudden changes in current flow" - true.
"which in turn can smooth out unwanted voltage ripple" - true, but that's not their main use in switching converters.
Very good also, but he got the point across with out going over a bunch of heads!
Olá !!! amigo sabe me explicar por que a limalha de metal não grudou em toda a extensão da bobina ficou presa ( grudou ) apenas no canto esquerdo ??? em 2:24
You saved the day.
Russians are smart!
Thanks keep it up i wish if you could explain in depth how many turns of an inductor or of a wire around a reed switch is needed to turn it on or if you could recommend a website or a calculator to do such task
How can i build something like that inductor tester?
Am so much at the right place. This is the best ever tutorial after i wasted my two years on other channel to keep on feeling like quiting electronics.
I love your JLPCB ad, but more than that, I watched your hammer smashing section twice, and laughed out loud both times! I'm laughing now, just thinking about it :)
I wish I know all this at my university, it is so clear and visual thank u👍👍👍
Thank you very much for your explanation and presentation. Great video.
That's one of the best demonstration of flyback ..
I’m quite new to electronics, so my use of a 12v relay is limited. I plan to have an Arduino controlling a few 12v lights with a relay board designed specifically for Arduino. Would I need to worry about any kind of voltage spikes if I isolate the 12v circuit from the 5v of the micro controller? I was under the impression that relays were safe but now I’m unsure 😅
Inductors are useful for buck-boost converters too. They take advantage of the voltage spikes to produce higher outputs than the input voltage.
@Fred Garvin how come?
@Fred Garvin So how do you get a higher output voltage then? As far as I know it occurs when you cut the supply to the inductor, causing its field to collapse and it generates a back emf. The duty cycle is to regulate the output voltage and with higher switching frequencies you can get higher voltages from smaller inductors because faster current disruptions cause higher back emfs.
@Fred Garvin boost needs the back emf of the inductor that occurs when you disconnect the power and it tries to keep the current going.