Magnets - Page 1
Forum section: electronics / general

author: EvilLOON
author_rank: Contributor
timestamp: June 11, 2015, 11:05:40 pm
content: Hey guys, what do we know about magnetic motors? Trying to read up on these things. Finding fact in the piles of fiction is just blowing my mind. Every one claiming free energy or perpetual motion.Answer appreciated and also any reading material is welcomed.

author: Len
author_rank: Frequent Contributor
timestamp: June 11, 2015, 11:53:33 pm
content: Quote from: EvilLOON on June 11, 2015, 11:05:40 pmStart with these two facts:1. All electric motors use magnetism.2. Any device offering free energy or perpetual motion is bullshit.

author: rolycat
author_rank: Super Contributor
timestamp: June 12, 2015, 12:09:09 am
content: Quote from: Len on June 11, 2015, 11:53:33 pmYou need to be more careful about your "facts". For example, electrostatic motors don't use magnetism, and a solar panel is a very practical device offering free energy.For the OP, using Wikipedia instead of YouTube as your information source would be a start.

author: Len
author_rank: Frequent Contributor
timestamp: June 12, 2015, 12:22:32 am
content: Quote from: rolycat on June 12, 2015, 12:09:09 amYeah, ok on the electrostatic motor, but "free energy" does NOT mean solar energy or wind energy or your parents pay the electricity bill. When EvilLOON reads about "free energy" on the internet it means energy from nothing and it is a scam.

author: EEVblog
author_rank: Unknown
timestamp: June 12, 2015, 12:42:36 am
content: Quote from: rolycat on June 12, 2015, 12:09:09 amRubbish. A solar panel is a circa 20% efficient converter of solar insolation into electrical energy."Free energy" means a system where "more energy out than put in", "over unity", "perpetual motion" etc, and always involves breaking the known practical laws of physics. If it's not breaking the known practical laws of physics then it's just called "engineering".

author: rockets4kids
author_rank: Newbie
timestamp: June 12, 2015, 12:49:27 am
content: The key word there being *converter* of energy!Also, one thing people often forget is the amount of energy that goes into the production of solar panels. That actually represents a substantial percentage of their costs.Furthermore, it is always important to look at the payout on solar systems. Historically, when panels were more expensive and electricity was cheaper, your typical break-even point was 15 years. And that figure generally doesn't include the cost of storage batteries.

author: BennVenn
author_rank: Regular Contributor
timestamp: June 12, 2015, 12:51:27 am
content: Well while we're on the topic of free energy...Water evaporates at temperatures far below its boiling point. This is due to random collisions giving other molecules their own kinetic energy allowing a phase change to occur? Does this mean the vapour being liberated is at a higher temperature than the water itself? And the liquid at a lower temp?

author: rolycat
author_rank: Super Contributor
timestamp: June 12, 2015, 12:56:18 am
content: Quote from: EEVblog on June 12, 2015, 12:42:36 amNot rubbish. Look up "Free energy" on Wikipedia and the pseudoscientific coinage is number three, after its uses in science and the economic sense of renewable energy.The scam artists and fruitcakes misuse a number of legitimate scientific expressions through ignorance and/or cupidity; that doesn't mean we should abandon them.

author: IanB
author_rank: Super Contributor
timestamp: June 12, 2015, 01:00:50 am
content: Quote from: rolycat on June 12, 2015, 12:09:09 amThis is pointless pedantry. Within the general meaning of electric motors, as found universally in refrigerators, washing machines, electric drills, DVD players, cooling fans, cars, trains, cordless screwdrivers, escalators, and who knows what else, all use magnetism. Please don't be a jerk.

author: rolycat
author_rank: Super Contributor
timestamp: June 12, 2015, 01:11:18 am
content: Quote from: IanB on June 12, 2015, 01:00:50 amI know I'm a pedant, but I have no wish to be a jerk. I'd just like to point out that there are far more electrostatic motors in the world than electromagnetic ones

author: calexanian
author_rank: Super Contributor
timestamp: June 12, 2015, 01:13:00 am
content: Here is a nice page on AC motor operationhttp://www.johnsonelectric.com/en/resources-for-engineers/ac-motors/principle-of-operationAnd here is the counterpart site discussing DC motors. The whole site in good as a matter of fact.http://www.johnsonelectric.com/en/resources-for-engineers/dc-motors/principle-of-operation

author: IanB
author_rank: Super Contributor
timestamp: June 12, 2015, 01:18:04 am
content: Also a couple of nice "how it works" videos here:https://youtu.be/-qS85aIvleQhttps://youtu.be/GNTvWxl3Isw

author: BennVenn
author_rank: Regular Contributor
timestamp: June 12, 2015, 01:47:04 am
content: Quote from: rolycat on June 12, 2015, 01:11:18 amOK, I'll bite. Examples please?

author: coppice
author_rank: Super Contributor
timestamp: June 12, 2015, 01:52:38 am
content: Quote from: EEVblog on June 12, 2015, 12:42:36 amRubbish. Free energy meansIget out more thanIput in. Don't let the crazy people co-opt basic expressions in the English language. Its free if you ain't paying for it, either in cash or consequential damage.

author: Tinkerer
author_rank: Frequent Contributor
timestamp: June 12, 2015, 04:10:47 am
content: Regardless of their intent, I have heard of a couple arrangements of magents that cause motion, but it seems to demagnetize them in the process. Energy comes from somewhere, in this case by draining the magnets? Dont know, best I heard havent researched it.

author: calexanian
author_rank: Super Contributor
timestamp: June 12, 2015, 04:11:05 am
content: Quote from: wilfred on June 12, 2015, 02:11:05 am+1

author: SeanB
author_rank: Super Contributor
timestamp: June 12, 2015, 04:54:30 am
content: Quote from: BennVenn on June 12, 2015, 12:51:27 amYes, the energy of the molecules assumes a distribution about a mean value, which in the bulk water we call temperature. As the molecules with the higher energy leave the liquid to vapour the average energy of the remainder drops, which means the temperature is lower. Also called evaporative cooling, and can be assisted by having air flowing ofer a water surface to reduce the vapour pressure on the interface so more molecules can leave with only a small energy excess from the bulk.

author: ranch varment
author_rank: Regular Contributor
timestamp: June 12, 2015, 05:59:46 am
content: Look man, if you dont think a magnet moves by its own fruition for eternity, I guess you just dont believe your eyes.Here, think of this, if magnets werent perpetual energy, your fridge magnets would eventually slip off, and i dont think that happens.So you lot dont know how illogical you are being.

author: hamster_nz
author_rank: Super Contributor
timestamp: June 12, 2015, 06:15:03 am
content: Quote from: ranch varment on June 12, 2015, 05:59:46 amOh, so glue is perpetual energy? As is sticky tape and bluetac :-)

author: IanB
author_rank: Super Contributor
timestamp: June 12, 2015, 06:41:46 am
content: Quote from: hamster_nz on June 12, 2015, 06:15:03 amAnd gravity of course...

author: rolycat
author_rank: Super Contributor
timestamp: June 12, 2015, 08:20:49 am
content: Quote from: BennVenn on June 12, 2015, 01:47:04 amYou've got billions of examples inside you right now. Bacterial flagella are driven by a rotary motor which spins at around 20,000 rpm. They are incredibly efficient nanomachines which are powered by an electrochemical ion pump. This creates an electric charge difference between stator and rotor which together with the differential ion concentration creates a motive force. The exact mechanism is still not well understood, but it seems to be a kind of electrostatic proton turbine.

author: Galenbo
author_rank: Super Contributor
timestamp: June 12, 2015, 09:44:09 am
content: Quote from: rolycat on June 12, 2015, 12:56:18 amSaid the noob to the scientist, the noob uses his own definition of energy, and changes that definition when needed.Quote from: coppice on June 12, 2015, 01:52:38 amI can give you the address where there's free energy for you.It's an all-in hotel, when we arrived we discovered there is electricity in the wall, and we didn't have to pay for it.

author: EvilLOON
author_rank: Contributor
timestamp: June 12, 2015, 09:44:44 am
content: Ok back to point guys. What I was asking is can a magnet drive a motor. Magnets like anything else do have a life span. What I'm trying to find is facts. I don't believe in free energy. I appreciate the feedback I have received from people on the site up to this point. The site seems like a good place to have intelligent, open, and fact filled discussions. By no means was the post meant to be a troll."Every one is claiming free energy or perpetual motion", is how that should have read. When you even type stuff like "magnetic motor", into google, you get a heaps of lies and fiction about magnetically driven motors. I do not believe in any form of "free" energy. I am truly curious, if a simple motor could be built with magnets.Can you propel a magnet around a circle with other magnets? That was the question. I do know magnets do loose their field over time and that under other magnet forces they will become demagnetized.I type short posts generally because I have nerve damage in my right hand. I went from typing 90 wpm to about 20. EvilLOON has been my screen name since 1997, and can easily be searched to see I am a real person.

author: BennVenn
author_rank: Regular Contributor
timestamp: June 12, 2015, 09:54:36 am
content: Quote from: SeanB on June 12, 2015, 04:54:30 amDoes the vapour loose its gained energy once it leaves the water? Is the vapour cooler, warmer or the same temperature as the water it came from?Rolycat, 20,000RPM!? I would imagine the drag on the outer surface of the spinning part would be enormous - have such a large surface area to volume ratio that is...

author: Galenbo
author_rank: Super Contributor
timestamp: June 12, 2015, 09:56:08 am
content: Quote from: EvilLOON on June 12, 2015, 09:44:44 amIf you are truly curious, you can put a proportionally truly effort in studyingexistingmotors.The first page on Google won't transfer you to a list of decent literature and study books on the topic, at least not with a short search term.I can give you a tip: Lookup what books of what autors are used by universities. Most of them cover multiple AC and DC motors, and explain differences between them, in construction, use , performance and rendability.Some words you will bump into are induction motor, bldc, slipring, synchrone motor, servo, steppermotor, and so on.If you have the right prior knowledge about math, physics and electrics, then after only 100 hours of dedicated study you will understand the basics. Then it's time to deepen out, or to see if you can change or invent something.

author: Delta
author_rank: Super Contributor
timestamp: June 12, 2015, 10:21:47 am
content: An entire thread of trolling and unbearable pedantry! Superb! 😀

author: EvilLOON
author_rank: Contributor
timestamp: June 12, 2015, 10:39:49 am
content: Thank you Galenbo. I will give that shot. Been building computers for years and never gave a thought to the underlying electrical mechanics. Recently started reading anything and everything about electronics. Beyond that, once you get to a point, you start googling dead ends about certain techs. I'll try going down the route you have suggested. I have recently started reading about induction motors and that's what started my line of thought on a motor driven by a magnet.QuoteLearning all that stuff too.

author: Unknown
author_rank: Unknown
timestamp: June 12, 2015, 10:56:18 am
content: Quote from: EvilLOON on June 11, 2015, 11:05:40 pmThe energy from a perpetual magnet motor is free but only if you don't have to pay for the magnets that go in them! also the load applied to the motor is probably proportional to the how fast the magnets will wear out, then have to be replaced.

author: EEVblog
author_rank: Unknown
timestamp: June 12, 2015, 11:25:51 am
content: Quote from: rolycat on June 12, 2015, 12:56:18 amWhat has an (un-numbered) list on wikiepdia got to do with priority of meaning?If you come on an engineering forum and you start talking about "free energy" and magnets, Tesla, or motors etc, everyone damn well knows (or immediately suspects) you are talking about "free energy" in terms of pseudoscience - i.e. over unity, more energy out than you put in etc.If you want to talk about solar only a fool would use the term "free energy" around technical people, it's a very poor choice of term in that context unless you very specifically clarify it.QuoteOf course not, feel free to use it in that context if you wish, just realise that many technical people will immediately put you into the loony bin category, and that's a fact, like it or not.

author: John Coloccia
author_rank: Super Contributor
timestamp: June 12, 2015, 11:48:06 am
content: Quote from: EvilLOON on June 12, 2015, 10:39:49 amThe basic answer is no, there is no such thing as a "magnet motor". Magnets fields are not energy, just like gravity isn't energy. You can USE gravity to store energy, or convert stored energy to some other form. For example, you can lift a bowling ball over your head (storing energy in the bowling ball...it now has a higher potential energy). When you let go, gravity converts that stored energy to things such as motion (the ball falls) and heat (there's a bit of air drag).Magnetic fields...all fields and forces, actually...operate the same way. You can't extract net energy from them because the only energy they're associated with is whatever energy you put into it. If you push two repelling magnets together, the most you could possibly get back out in the form of useful work is however much work it took to push them together.Theoretically, there is SOME, truly tiny amount of energy that went into magnetizing the magnet. In other words, it took some work to line up all of the dipoles to make a bulk magnet. There's nothing that says you can't extract that energy somehow, demagnetizing the material in the process. How, I don't know, but it's not worth it. Think about how little energy is actually there. Want to magnetize a screwdriver? Just drag it over a magnet once, and it's done. Good luck doing something useful with that puny amount of energy.Now, it's not so obvious exactly WHY a magnet motor can't be made to work, but you should be able to answer immediately that it absolutely can not work just based on basic principles. WHERE is the energy to make it work come from? Nowhere, that's where, so it simply can not work. I'm not going to ruin the fun, though, so I'm not going to explain just exactly what causes them to fail. Normally, perpetual motion machines fail predominantly due to friction, but the typical magnet motor is a special kind of stupid because it wouldn't work even if there was NO friction. You can have some fun researching and thinking about it.

author: hayatepilot
author_rank: Frequent Contributor
timestamp: June 12, 2015, 12:23:38 pm
content: +1John Coloccia is absolutely right.Quote from: Mr Eastwood on June 12, 2015, 10:56:18 amMagnets don't wear out and all the "free energy magnet motors" don't work. Every video showing otherwise is fake.Normal electric motors work on electricity, not magnets, even if they have permanent magnets in them.They are calledpermanentmagnets for a reason. They hold their magnetic field almost indefinitely. The only things that weaken the field is corrosion, high temperatures and other stronger magnetic fields.I know I should not feed the trolls, but I can't let such a false claim stand, in the end someone would probably believe it.Greetings

author: GK
author_rank: Super Contributor
timestamp: June 12, 2015, 12:57:35 pm
content: Quote from: EvilLOON on June 12, 2015, 09:44:44 amI was on free energy before I moved out of my parents place.

author: Sigmoid
author_rank: Frequent Contributor
timestamp: June 12, 2015, 08:36:01 pm
content: Quote from: EvilLOON on June 12, 2015, 09:44:44 amNever heard of anything like that, and I'd be surprised if it was possible. Powering a motor by "demagnetizing" a magnet is not a thing. The energy difference that could be extracted from such a change is miniscule anyway, and wouldn't get you very far.The closest you can get to a "magnetic motor" is a mechanical setup where you store energy in the position of two magnets that are aligned to attract or repel each other, and extract that in a controlled manner as mechanical energy (the magnetic equivalent of a spring drive)... Or you can just use a spring and be done with it.

author: Delta
author_rank: Super Contributor
timestamp: June 12, 2015, 08:45:05 pm
content: I have used a successful free energy device a few years ago.It was a length of 16mm^2 wire across my electric meter. Worked a treat!

author: Sigmoid
author_rank: Frequent Contributor
timestamp: June 12, 2015, 08:51:00 pm
content: Quote from: Delta on June 12, 2015, 08:45:05 pmI remember reading about a "solid state free energy generator" that turned out to be a device that steals power from high voltage cables running above the "inventor's" house.

author: EvilLOON
author_rank: Contributor
timestamp: June 12, 2015, 09:15:23 pm
content: QuoteThat sounds like the old story of the farmer that created an inductor to syphon EM off the transmission lines. I never put much faith into that story though. Seems to be no evidence to truly support the story itself. Some of the light reading I have done on Faraday's law, has used this as an example but no citing source.*sarcasm* Who wants to be the first one to test this and go on record?

author: John Coloccia
author_rank: Super Contributor
timestamp: June 12, 2015, 10:11:51 pm
content: It's pretty common, actually. Have you ever seen where someone holds a fluorescent tube near high voltage lines, and it lights up? That's stealing energy from the wires. There's not a tremendous amount you can reasonably grab, but it's actually enough to do some useful work.

author: ranch varment
author_rank: Regular Contributor
timestamp: June 12, 2015, 10:22:05 pm
content: Now how many of you have actually spun a wire against a permanent magnet before hmmm?

author: BennVenn
author_rank: Regular Contributor
timestamp: June 13, 2015, 02:57:30 am
content: I remember back in high school we set up a length of wire on the sports oval with a multimeter attached and swung it around like a skipping rope, we did this in both orientations N-S + E-W to see the induced current from the earths magnetic field.

author: TMM
author_rank: Frequent Contributor
timestamp: June 13, 2015, 05:29:18 am
content: we can't have a thread about magnets without someone posting this

author: GK
author_rank: Super Contributor
timestamp: June 13, 2015, 09:50:53 am
content: Quote from: TMM on June 13, 2015, 05:29:18 amYes we could've had.

author: Muttley Snickers
author_rank: Unknown
timestamp: June 13, 2015, 11:27:02 am
content: Quote from: TMM on June 13, 2015, 05:29:18 amAnd for more extreme profanity, children dont watch this without adult supervision.Muttley

author: Unknown
author_rank: Unknown
timestamp: June 13, 2015, 11:51:58 am
content: Quote from: hayatepilot on June 12, 2015, 12:23:38 pmi feel like a complete tw*t now! i'm not a troll i've been an eevblog member for a while and i created 4 of the new forum icons a while back - which makes this kinda worse!!so long - it's been fun!

author: amyk
author_rank: Super Contributor
timestamp: June 13, 2015, 01:15:50 pm
content: Quote from: John Coloccia on June 12, 2015, 11:48:06 amHave you seen the magnetisers they use to create permanent magnets? The amount of energy used is huge... but the efficiency of the process is very low.

author: John Coloccia
author_rank: Super Contributor
timestamp: June 13, 2015, 02:03:02 pm
content: Thinking about it, the only energy you could probably get out is the energy of the collapsing magnetic field, i.e. you may be able to get a miniscule amount of current in a wire for a tiny fraction of a second, but certainly no more than you put in to set up the magnet in the first place.

author: G7PSK
author_rank: Super Contributor
timestamp: June 14, 2015, 09:03:45 am
content: There is no such thing as a permanent magnet, only long lasting magnets. Any one who has restored vintage engines will know that often you have to get the magnetos magnet re-magnetized as it has become too weak. Permanent magnets de magnetize with age from heat,vibration and shock, sure the newer types last longer or are stronger but they still have the same problems. At one time magnets were made by black smiths lining up a piece of steel or iron with the earth's poles and then hitting it with a hammer you can do this yourself no real skill required, similarly you can take a magnet hit with a hammer while going around the compass points and it will loose its magnetism. Also take a magnet heat it in a flame and it will also loose its magnetism the hotter you get the faster it de-magnetizes. The heat and the shock and vibration cause the molecules and atoms to vibrate and rearrange themselves and not all will return to their original positions and room temperature is enough for this to happen, I have a horse shoe magnet (made by Eclipse) that I got in the mid 1960's it has always been treated carefully and spent most of its time in a drawer but now it it will only lift a few grams where when new it would lift something like a kilo.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 14, 2015, 09:30:51 am
content: Poor old alloys like hard iron and Alnico lose magnetism spontaneously when not kept in a closed circuit (i.e., using a keeper). Likely your vintage style magnet has seen a combination of things, like improper use, improper storage, and poor formulation.Modern alloys (since SmCo or so) have excellent retention characteristics and droop no worse than log(time) (possibly a related mechanism to ceramic capacitor aging -- both are ferroic materials after all). If not being subjected to high peak loads (e.g., surges in a motor), the biggest hazard is probably just thermal (keep them cool and safe, and they will last for decades or centuries).Tim

author: G7PSK
author_rank: Super Contributor
timestamp: June 14, 2015, 09:40:31 am
content: The old magnet has always been kept with a keeper on it and looked after lovingly. The new type magnets such as Neodymium will still loose magnetism over time might be i 80 years or more but loose they will and with the application of heat it can be virtually instant, I have heated one in an oxy propane flame to see what happens, they explode apart from loosing magnetism.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 14, 2015, 09:46:56 am
content: Duh..?Actually that would've exploded from a combination of magnetic force and thermal shock. NdFeB is 100% intermetallic, i.e., it's shiny and metallic, but as brittle as ceramic.If you heat it very much more slowly, the exotherm due to demagnetization will be quite small compared to the total heat capacity of the material, though still measurable.Tim