A buddy of mine owned an old BMW from the early 60's. The generator and starter motor were the same. When the key was in the start position it was wired as the starter motor and when the key dropped back to the run position, it was wired as a generator. It worked great until it didn't. ;-)

I never thought about doing that. I know motors can be expensive and you certainly got the alternator for the right price. Great video!

Your joyful laugh is great to brighten anyone’s day. Thanks for sharing Rob! Here’s something for you! SMILING ... from Steve Judd Smiling is infectious; you catch it like the ‘flu’. When someone smiled at me today, I started smiling too. I walked around the corner, and someone saw me grin, And when he smiled, I realised I had passed it on to him. I thought about the smile, and then realised its worth. A single smile like mine could travel round the Earth! So if you feel a smile begin, don’t leave it undetected: Let’s start a pandemic quick, and get the world infected!

I have a 1500+ watt controller, and a few alternators to do this with, I have smaller bldc motors, that are not rated for the higher voltage of the controller, 48-72 volts, I'd say the alternator can handle it, my lil 350w 24-36v motors wouldn't last to long at 72v! A unrelated alternator can output as much as 600+ volts at a decent speed, some more some less, the 12v output, is with the rotor being pulsed rapidly, 12v on the rotor, at 2k rpm the alternator will easily do 18-36v open circuit, it's amazing how little alternators have changed since the 60's! Great video, I hope to see more videos like this! Awesome!!

You should definitely try to make it into a full BLDC motor! I think all you'd need to do is get some neodymium magnets and "place" (well, grind out slots, and epoxy) them onto the rotor. That way you do away with the brushes and hopefully, make it into an actual, brushless DC motor. Would help with efficiency too!

By using a variable DC source to power the brushes (field winding), you will be able to implement field weakening. Weakening the field allows higher RPM at the expense of torque which may be useful for a vehicle without a gearbox. On the other hand, leaving field current high limits rpm to whatever generates back EMF equal to the 3 phase supply voltage. "Electric Motors and Drives" by Austin Hughes was, and may still be available for free download as a pdf and is an interesting read.

Love to see you guys incorporate this into a windmill optimized with your graphene projects!

You,ve nailed it , easily explaned and understood . Looked at a few other videos and I must say this is the best I,ve seen ,not too winded ,to the point and effective .Thank you so much .

I always loved to do things like this just to do them.. We did make an old alternator into a motor back in the old days.. just to see if we could.. what fun!!!!

Very nicely done, well explained and joyful to listen.

If you connect 2 of these in paralell (each wire 1 to 1 w/ the corresponding 2nd unit's wire), then energize the rotor (slip rings) w/ single phase AC (use your variac) enough to provide excitation, you will have a Synchro (or Selsyn) system. Rotating one shaft slowly, and the other shaft will follow it, remotely reading the other input. Think a remote wind direction indicator. Energizing with DC, then driving one shaft at high speed, the other shaft will "motor" at the same speed. (this is like a power plant generating 3 phase AC, running a Synchronous motor at a customer's plant. Cheers, Dave Cole

I am working on a v4 outboard and I wanted to change its alternator (which is integrated into the flywheel) into a motor/generator so it can operate as a hybrid (add extra electrical power when taking off, and recharge it back when planing). I have two, one is newer and there is both the spark plug timing/capacitor charge and alternator in one, and it uses permanent magnets in an aluminum flywheel. The older version has a distributer and so the flywheel/stator is just an alternator. The flywheel also has those "V" shapes, and I finally figured out that is done because when the rotor is powered to make it magnetic, each "v" alternatives between the front and back, make them alternative between positive and negative poles. In my outboard flywheel, it has the coil inside the stator and inducts the charge to the steel flywheel to get the positive and negative poles in the "V"s. So it does not have any brushes to do this. I'm sure it is not efficient at all...this is like a 1965 outboard, vs the newer 1980 (haha still old.:) Just thought I'd mention that because it makes more sense of those "V" configurations.

Well done - great video, totally coherent, I know understand how an alternator works.

I have a delco external regulated alternator already set up to work like this, and a remanufactured one just like it to do something with also, got it for $15 , I was going to make a pma wind turbine! Maybe I still will, being offgrid, power is always in demand! A 20 meter tower that is needed is the hold up!

By the way, reversing the polarity of the field (rotor) brushes does NOT reverse the motor, but swapping any pair of the 3 phase leads of the stator will. Running with mechanical drive input (generator mode), adjusting the rotor (field) drive current will control the output voltage at any given shaft speed, it will also change the load on the device (turbine, engine, windmill ,etc.) When in motor mode, adjusting the DC field excitation is used to match motor HP output availability to that the load is demanding, which also controls the power factor (phase angle between Voltage and Current, lead or lag), which can make a synchronous motor appear Capacitive, Resistive, or Inductive, depending on field current. Power utilities like to see unity Power Factor (in phase aka resistive loading). HTH Cheers, Dave

back in the 60s & 70s when working on an alternator, replacing brushes or voltage regulator, we'd use a toothpick to hold the brushes in place, which worked rather well.

Thank you. First time I become able to know how the electromagnets of a alternator's rotor works (by watching this video). This experiment is useful and entertaining too. ☺️

Thanks so much for what you do. What speed controller would you suggest? So many pop up on the net.

If the windings are in a Y configuration then thats Star not Delta, but the middle of the star would be a neutral wire which I didn't see on your coil so it must be wired as Delta.

Hey mate, that's by fare the easiest way I've seen it done. Hid I'd known this before I could have saved myself a lot work with only one difference. The difference is in my application I needed the diodes in place. As always mate, great video and good job. Thanks.

Awesome, great video, great motor and great price, on my to do list, thanks Rob, again

Great video Rob, love the happy vibe you give off whilst teaching such interesting things! did you use the Alternator(Motor) to drive anything in the end?

I have been planning a ebike, and sometimes you can't just buy stuff, and knowing how to make stuff can come in handy!

Many thanks for posting this educational video - well done.

i truly like the way you explain everything! you are wonderful! my friend! hope! i can shake your hand one day! thanks!! for teaching! me about this alternator!

Nice! Good idea using the thick wire. I may be trying it soon. Subscribed

I m having a go at this with the only knowledge gained from these videos and forums. I ve only got the alternator and get a short if I connect battery to brush terminals when they don't have continuity.a little knowledge is dangerous!

Seen this done elsewhere before but I don’t get why it’s good for any reason other than someone enjoys tinkering and they got it cheap or free because used motors aren’t too expensive and are designed to more efficiently do the job and you know how strong they are so you aren’t hoping an alternator can do a job meant for a 3/4HP motor. You buy a motor you know what RPM that motor will spin and what HP and what wattage demand it has. Again it makes perfect sense if someone wants to tinker and learn electronics.

All the 3 stator wires are positive? Sorry im new to this conversion, thanks for your time.

Thank you for an entertaining and informative video. Just one small point. I think I'm right in observing that you brought each of the stator connections out through a separate opening in the casing. Depending on how you are driving the stator these wires will either be passing AC or pulsed DC (which for the purpose of the explanation below has the same effect as AC). The problem is that by passing the the conductors through individual openings in a conductive material you are effectively introducing a 'shorted secondary turn' resulting in currents being induced in the the casing. The effect may be insignificant at the current levels involved in this video, but if you are intending to use a higher power driver as you suggest, then the effect may become significant - not only reducing efficiency - but also resulting in heating of the casing in the proximity of the cable insulation passing trough it. If you route all 3 conductors through the same opening you cancel out the magnetic field produced by the current and avoid the issue. You are unlikely to see a competent electrician passing individual AC carrying conductors through their own openings in a conductive material. Instead they will route all conductors carrying AC current from the same circuit through the same opening.

A very interesting way of getting a low voltage 3-phase motor

Rob has infectious enthusiasm in spades.

I'd like to know more about what you're feeding the stator with. Is it 3 phase sinewave? What would I look for in a controller? And guestimate on horsepower? Would it be a good candidate for a variable speed drill press motor? My antique drill press was originally ⅓hp which was ok, but the pulleys couldn't be set to a low enough speed for drilling stainless steel, so variable speed would be great.

EXCELLENT THE BEST ONE ON YOU TUBE YET, BUT YOU NEVER COVERED THE CONNECTIONS TO THE ALTERNATOR . SO CAN YOU REVISE THIS VIDEO THANK YOU

Great vids , could you run an alternor through an inverter to power 240 apliances?

Great. Please, can you at sometime demonstrate how to convert an auto alternator to an AC generator.

Another motor or engine project i find fascinating is the steam or 2 stroke motor from ac type compressor i bet if you aint seen it it'll get u thinking of possible way to use it

some early ebikes were built this way. swapping the rotor for magnets was a pita.

Thank you for your answer. What if the rotor connections were shorted? Could the 3 phase field induce a voltage into the rotor?

There is tons of possibility for applications using this as a motor...

curious in regards to the rpm, hp ...etc results you can get from one.

I have the exact same esc but am having trouble getting it to turn.....could you possibly show a close up of the esc wiring including the potentiometer please? Great video!

you can run an alternator like a stepper motor. I saw a video here on YT that showed doing just that.

I will genuinely say that for the power output, AND how totally rugged they are, since you can in fact get them for very cheap, you can not buy a commercially produced motor of comparable power and ruggedness for that kind of money.

Can you supply the accessories specially the speed controller & how much thank you

Can we made brushless alternator and make its efficiency as brushe alternator?

Legend cheers dude

That is awesome stuff! I really enjoyed watching you do that gives me great confidence in knowing that I could do it myself. It also gave me a great idea for you to try something that I've seen several times people do and that is taking a motor and attaching it to a flywheel then from a flywheel to a generator and somehow using the slip connection of the belts and the power stored in the flywheel to create a generator that will then make electricity on its own in sustain itself. I've attached a UKposts video that will give you some idea of what I'm talking about

Basically it's a three phase motor with the potential for varying the output by how much current is applied to the rotating field. You could use the controller to drive mosfets [mosfet has "Source, Gate and Drain"] which are sourced by house current or ...If three phase is available like in industrial shops then you use those mosfets but the gate's are variable controlled to limit the current applied to the stator windings. In both cases the mosfet must be able to handle the source voltage and current that is needed to apply to the stator windings, you MUST never exceed the current limits of both the mosfets or stator windings. There is a pretty good chance you could apply the three phase signal to the stator windings at a voltage that generates a nominal current drain...Then when you begin to drive the field winding with current, that would trigger induction to the stator and the shaft would begin to rotate causing stator current to increase. The amount of stator current would be related to the field voltage applied and the load put on the rotating shaft.

Thamks for rhe post. Im making an electric car for my grandson and wanted a motor out of what was laying around

what size wire did you use

I Like these videos Interesting, i wonder if you were to self loop the rotor if that configuration would still function like an induction rotor , that is to say universal opposing force? The way in which the metal core is folded would suggest it may. Then if you disconnect the winding to their individual 3 windings you will be able to identify the 3 phases. And you have a 3 phase motor, which can then be operated by adding a ‘condenser’ to run single phase or by self looping one phase and connecting the other two in circuit I believe. But I’d have to try it. The advantages of a pulse control is you have speed control, as you would know induction motors are frequency dependent However, there are also then generator options with the induction motor as you have already outlined and you lose the brushes this way so? And other advantages like being very prevalent at most local tips or scrap yards. Oh I just thought but to self start you would need to check the L and the R of one winding to determine the phase angle You can use Arctan { xl / R} To get the phase angle The you would use on another phase Arctan {xl - Xc / R } to sum that offset phase angle so it is 90deg alternate to the phase you run Then it should self start, but I’m not sure as to the self connection on the third phase I’d have to try , I have some old alternators I might try it. Regards

My latest project video can be easily used as a variable frequency drive for you. You will need one amplifier per phase and have a multichannel input with 120° phase shifts between channels for 3 phase. Probably much cheaper than a commercial DC input to 3 phase VFD. I found it much more fun to build as well!

Are the outside coil windings 'serpintine' ?

He's mucking around! That sounds funny to us Americans ! 😁♥

Awesome¡¡¡ To me brushless dc motors are so expensive... this may be the solution I'm looking for an ebike...

How is the A B and C connected to the speed controller.

What about wiring the magnet wires into the speed controller so you can power both with 1 power supply and also increase the efficiency. You would need a transformer to get the voltage right for each but rectifiers are only a couple cents so you can even switch from AC to DC.

Slip ring motor. Never heard of one? Very common before VSDs became common. Delivers speed\direction control of large motors in machines like cranes for example.

Extra Quality !

So,if you remove the 3-phase power feeding, instead turning the shaft with whatever sounds fun, then you got a 3-phase generator, output voltage regulated by changing the 12V and the frequency by the speed you turn the shaft, right?

Is that work without hall sensor ...you thenk that is ok without sensor??

how do you connect the three cabels coming out of the altenator? i understand you connect the plus and minus of the bruches to the speedcontroler. but i do not understand how to connect the three cabels since you only have a plus and minus. do you connect two of them together?

How will you connect a 4 wire stator, need help here thanks

How mutch amps vill the generator stand? Befor itse broken.

You have to swap one of the 3-phase legs with another one swap any two of the three phase input it will reverse the direction

Can you run it without a speed controller? And if so how? Can you use a single source power supply for both if not using a controller

You were right! I new I'd had to have seen your video! Lol

Reversing the rotor polarity won't change the direction of rotation. To do that you need to swap two of the stator phases, or have the controller cycle the phases in the opposite order.

You need to do next is hook do another one like that and you can have a perpetual energy machine,the alternator would drive the motor that's driving it,making more power then what's being used.(overunity)

Could this be configured to work BOTH as an Alternator OR a motor? If so, it could be used as a pseudo Hybred system, if reinstalled on the original vehicle.

Would it work as a three phase induction motor without the D.C. voltage on the rotor?

You said, you put 5v. To the rotor. But then you mentioned 12v.? Also, where did you hook up to get the five v.? I fly rc airplanes, and have numerous esc’s. So I understand that side.because the little ac motors on airplanes have three wires, but are brushless, in ductive. Did you get your 5v. From the small three wire connector off the esc that hooks to your servo tester? Or on an rc, it would connect to the crafts radio reciever. And as a side note. Esc’s are cheap to purchase, for low amp ones, but they get very expensive for the high amp ones. I suppose one could double or triple them up to give the alt/ motor more power. Cool video.

WOW! I think I'll have a go at one to drive my generator.

A similar generator pushes my car with a driver and a passenger. I like it. I also like to make interesting projects, one of which I do on my UKposts channel

Hi rob, can you please show me how to put the wires to a electeic fence, to give it a bit more power to stop the cows getting out. I have done what you have shown me but get hot and

I wonder if it would be possible for someone to manufacture permanent magnet rotors that fit a variety of alternator models and sell them online. It would be nice if people could just simply swap out the rotor on their salvaged alternator and *bing bang boom* you’ve got a nice big BLDC motor.

Will you explain how the generator works? I'd like to be able to make a motor with mine.

I wonder how one would run at 72v 20a....🤔 And about how many watts would you say it would be?

If you reverse the polarity of the brushes it will not change the direction of rotation

i like your ideas .

You havent confirmed is the stater voltage ac or dc sir

Quarantine fun..

Very useful conversion. I tried to make a motor out of a bicycle dynamo once. Didnt work. Anyone know why? Maybe cause its an ac generator? How could you do it with a bridge rectifier?

Hi, how about converting a gasoline gensets alternator into a motor?

interesting , my suby alternaters are rated at 100 amps ,[ unlikely to be 100% duty ],even at 50 amps 48V you should have a couple of killowats ,very usefull for a bike . may be able to up the field voltage before saturating, for a bit more . Could actually be interesting to really up the voltage and limit current aka Charles Newman , have to rewind rotor though. I take it that is a 3phase speed controller ? pretty amazing the controllers you can get for drones and things . dang! now you've got me thinking ,how many of those to get a personal flying machine on the cheep ...now all we need is some really good light wieght batteries ....... !?

The plug with the electronics. Is the charging regulator. It communicates with the cars computer to know exactly how much voltage and amperage to output according to the cars electrical demand. It usealley works off of a bus can data and/or 5 v reference on obd2

Three wires = Delta. Four wires = Wye. Right? So this looks like a Delta. Correct me if I'm wrong.

Depending on how you connect and feed power to the 3 separate phases of this system you have, you can actually make it a fully speed controlled, reversible motor at virtually any speed up to its self destruct speed limit [centrifugal force]. ~( 'w')/ I have seen people wire these up with as much as 72 volts and using a phase controlled field modulator, run them in excess of 10,000 RPM on go karts for the duration of the batteries [which at these power levels, require quite robust batteries, as you can imagine] ~( 'w')/ I have heard people claiming as much as 5 horsepower for as much as 30 minutes nonstop under load without overheating them, so if they are set up well, one can use them for pretty punchy little electric vehicles [go karts, bikes, very small boats and the likes, possibly even a large model airplane].

So you are saying that it is almost the same thing as a brushless motor except that it is not brushless. Actually though, it is relatively simple to actually make it brushless, with a corresponding increase in efficiency. The expensive but simple and extremely efficient method is to remove the rotor windings and replace them with one large donut magnet, retaining the pole pieces, so instead of one large electromagnet with the poles distributed radially, you have one permanent magnet with the poles distributed radially. The not quite as good but MUCH cheaper way is to drill or mill into the pole piece claws and mount round or bar magnets, with the poles of course alternated. An intermediate method is to make a magnetic rotor to replace the windings and the pole pieces, both. Do that, add hall effect sensors, and upgrate your bearings and instead of just an academic exercise or very very general proof of concept, you actually get a motor that with the correct controller operates at around 90% efficiency, at 1/10 the cost of a commercially available motor operating at 90% to 92% efficiency. This makes the end result very practical, instead of just youtube content for the purpose of making youtube content.

O boy I"ll bet the price of alternators will go sky high please don't tell the scrappers what you 'er going to do with it!

Unable to see connections with closeup everything is suspence

You mentioned turning it into a generator. Can you explain that a bit further please

Awsome....Stick it in an ebike!

Is it "Ajvan" or Ivan?

Funny I should watch this tonight after getting all my pulleys and motor in place and then to find the first motor was broken and then my alternative to have a 240 supply with a bridge rectifier in it. Unfortunately I dont have a speed controller for dc so spent a lot of time learning more useful stuff on ac to dc circuits and bridge rectifiers. I'm just happy I love learning lol

Do you want to sell one of them to me and if yes how much do you want for it mate ??

I have 4 wires instead of three

Every video like this I watch they don't explain how to hook up the three wires

This may be dumb but why can't ev cars have each wheel run a motor like this to charge battery when wheels are turning?