500 An Induction Motor As A Generator Without Altering The Motor 

'Motors as Generators in Micro-Hydro Power' by Nigel Smith is probably available thru your local library, and gives a comprehensive guide to setting up an induction generator, selection of capacitors for induction generators, with a good description of the process to get the motor characteristics to calculate the capacitance, and a number of sample calculations to guide you in the (not overly difficult) process. The capacitor is used to cancel out the reactive (inductive) current that the motor draws, apparently. This reactive current is relatively constant over the range of power outputs from the motor. A fair approximation of the required value can be found by (a) measuring the current drawn by the motor at no load, preferably with the cooling ducts blocked, to reduce the actual work being done by the motor. That current is mainly magnetising (inductive) current, with only a small 'true power' current driving the reduced windage, bearing friction, and low iron and copper resistive losses. (Some of the measured current is still driving resistive losses in the motor, but at no load, and with the cooling duct blocked, these losses are minimised, and most of the current will be reactive.) Then, (b) determine the reactance of the motor to draw that current. XL = V / I. That gives the approximate reactance the capacitor needs to have to compensate for the motor reactance. (c) The capacitance can now be found from C(uF) = 10^6 / (2 x pi x f x Xc). Example: a 1kW single phase motor draws 2.3A from a 230V supply at no-load. The motor reactance is approximately (230 / 2.3) ohms = 100 ohms. The capacitor that will also have approximately 100 ohms reactance at 50 Hz is.... (10^6 / (2 x pi x 50 x 100) = 31.8uF. That's the starting point for setting up the capacitor; it /will/ require a slightly larger capacitance to hit the 'sweet spot' for best operation. For 3 phase machines, refer to Nigel Smith's book. The principle is the same, but the capacitors may be connected in either star or delta, and the capacitances and voltage ratings are different for each of those cases. The capacitor is not a motor-starting type - these are rated for intermittent operation only, and often less than the motor voltage. (That's another story, though.) A polyester or other 'motor-run' capacitor is required, and should be rated at a higher voltage that the output voltage of the machine in operation. (Switching off a large load can cause a 50% surge in output volts in some machines!)

This is just a super channel for the electrically minded people. You, Robert have such a great way of teaching the subject matter at hand that your method should be used in schools all over the world. Getting to the point in a straight way is priceless. Keep up the great work fella and God bless.

I have heard folks say your mad.. or your a hustler.. But frankly I don't think they are smart enough to see what it is you are doing.. I find your videos refreshing and straight forward.. I think in this day when a lie is now the truth and the truth in now the lie.. people do not know how to listen and see straight.. You make me think.. you force my mind to actually see what is before me and wonder at the amazing things we have all taken for granted. Not just to flip a switch and expect the light to come one but actually question what makes the light come on and can I do something like it with out all this rigmarole. To explore as we all did as kids our world and see what it real is all about.. thanks Robert.. you make me feel young again..

I live in NE Alabama and back in the 90s we had an ice storm that knocked our electricity out. I had a Chevette car with a diesel motor and I had a 120 hp 3 phase motor. We mounted a wheel with a tire to the induction motor and jacked the car up and placed the tire that was mounted to the 3 phase motor against one of the rear tires on the Chevette. The motor was a 460 volt 3 phase motor so I only used 2 of the three wires and ran the output through a transformer to get 240 volts. Then I added a large bank of oil filled capacitors. I adjusted the speed of the Chevette engine to give me 60 hertz. I connected the system to my home and we had electricity all night...only had to add more diesel fuel the next morning...worked great! The trick to using an induction motor as an alternator is to exceed the rated RPM of the motor and add enough capacitors. This was before I had a smart phone to video the system....TRUE STORY!

Im currently in ukraine trying to create backup generator from whatever junk we have at hand we dont have drill for metal nor magnets nor good glue and oh boy god bless you for this video we actualy do have some old stand fans here at junk piles and we can actualy find capasitors i will still need quite some time to figure details out im a newbe when it comes to electronics but you my friend, is the one bringing hope to ukrainian refugies in the middle of the war

Robert, you have a gift for teaching and the same desire for knowledge that many of us do. Keep up the great work mate

While the mains freqency in many parts of the world is 50hz, in the US it is 60hz. A permanent magnet motor, is a synchronous type motor with its synchronous speed depending on the number of pairs of poles in the field coils. In the US a synchronous motor will spin at (60hz aka cycles a second) × (60 seconds a minute)/(number of poles/2). So in the US, with 2 poles making a pair in the stator, the synchronous speed is 3600 rpm. 2 pole pairs (4 poles) = 1800 rpm. 4 pole pairs = 900 rpm. In say the UK that would be 50hz ×60 seconds/(2/2)=3000 rpm. 50×60/(4/2)=1500, and 50×60/(8/2)=750 rpm respectively. Now induction motors are asynchronous type motors and they require a difference in rotating speed between the synchronous speed of the rotating magnetic field in the electromagnetic field coils, and the rotating speed of the rotor. Induction motors are generally rated at about 5% slower than synchronous, in the US (3600rpm becomes 3420rpm, 1800rpm become 1710rpm). Too much slip (over 5%) causes excessive heating in the rotor and field coils. Grid excitation: If you pluged an asynchronous induction motor into the wall and spin it faster than its synchronous speed, then instead of drawing power from the grid, it will generate electrical power pumping that power into the grid. Because of the induced currents inside the rotor cause heat in the rotor, you should not go any faster than about 5% faster slip than synchronous with the grid. For exampke, in the UK with 1 pole pair field winding motor 50×60/(2/2) × (slip factor 1.05)=3150rpm. Self excited inductlion motors store "reactive power" in the capacitors with the inductance and capacitance acting as a resonate capacitor inductor tank circuit. The resonate freqency (aka syncronouse speed) of the tank circuit in the most simplist terms, is a function of capacitor and inductance 1/(2×pi×sqr(L×C)). Adding resistance in the coils and load complicate the formula. Now it will continue to generate power as long as you dont try to pull too much power. Causing it to loose its self excitation. I don't have an equation for that.

Seriously i appriciate this vid. Even if you do not know the math. I only need to know the components. Your awesome

That was a great explanation - I picked up a couple of washing machine motors form a scrappy today and whilst I was familiar with the bushed type (which i got working), I was confused by the other one which appeared to have no brushes but spun a lot smoother. Thankfully I thought "I know who's probably done a video on this" and wasn't disappointed. Going hunting for an old microwave tomorrow for some big capacitors to make it work as shown. Thank you so much for your videos, brilliantly explained, especially in the context of wind turbines (which is why I'm digging into this subject).

Videos like this is what made RU-vid so great. Thank you for making this video.

I love watching your videos Rob. When it comes to electronics my mind goes like Homer Simpsons. I think I'd have to start with basic circuits and take it from there lol. Still there's something relaxing about watching a man who loves what he's doing and humble enough to listen to advice. We never stop learning. God bless mate 👍🏻

Thank you for bringing this up. I came to the same conclusions when I was studying for my exams in electromechanical machines, but because I had to study on, I completely forgot what it was that I had found. Good work, spot on! Love your series about universal and induction motors. Very well suited for wind energy. Also stepper motors. Great explanation and very visual

Hello. Very clever but so simple dunno why I'd never thought of that. Been trying to figure out how to do this for a while. I wish I'd seen this video before I pulled all the windings out of the stator and got loads of magnets. Oops. Very enjoyable as always to watch your videos. Thanks. John.

What a brilliant display of technology. Thank you, pulling out the spare single phase induction motor now.

The motor you took from the drill is not an induction motor. It is a "universal" AC/DC brushed motor. By definition, induction motors induce current in the rotor windings by varying flux. The don't have brushes. They can't run on DC. The drill motor will run nicely on DC.

Have wanted to build a peddle driven induction motor generator for a while, I found out previously that there is a sweet spot at a certain rpm for producing optimum power , would be great to exercise and produce a fair amount of power at the same time, gearing would need to be precise of course, love your videos, always learn something new :)

Very enjoyable Rob.Took me back to my days studying city and guilds electrical principles :-)

I'm loving your videos Robert, I've passed on your channel to our local makerspace to give them some ideas on teaching children interested in STEM

Thank you Sir, you've answered questions I've been contemplating for a very long time... very exceptional...!!!

if someone ever figures out how to keep someone alive forever you should be first on that list. what you provide to society is extremely useful

I have learned so much from you it's unreal. Thank you. All so useful for providing my shed with power without running it from the mains cable from the house. One request, diagrams, flash them up for a couple of seconds at end of video and i can freeze frame and screenshot.

Another great video, the way you teach its a lot of fun to learn. Thank you

If you combine this with the magnetic reduction gear you go over in another video, you have both the capability to accomplish speed control and also multiple speeds.

Thanks for this, it is not possible to look at all the videos at the time I did not know that I needed this. Now I do and this might well be the solution to my wind generator project.

just a ps for anybody starting to experiment with motors as generators , Take a tip and start with the ones found in the heater box or the radiator fan . They come with nice magnets and decent bearings . They will always generate and help teach about what you can get out of these devices. . Old battery drills also are a good way of learning with lots of fun bits.Even a bike dynamo with a diode will make a fun wind project spinning out in the wind running 3or for very bright LED'S or through a circuit charging phones for free . I my self like the hub dynamos we used to find made in the middle of some front wheels as they make wonderful wind projects for free small amounts of power so get looking . I;m wondering weather to start a channel?

Those brushed drill motors are called Universal AC/DC motors because they will run off either AC or DC. They run faster than synchronous speed, so I wouldn't strictly classify them induction motors. What they really are is a series DC motor. I consider an induction motor one where the armature's magnetic field is excited via induced current.

Okay, thanks for the good value, Robert M .Smith. great job.

I did this a while ago when i was stuck for a generator, i used a stationary petrol engine and hooked it up to a 3kw 240v ac squirrel cage motor and simply set the motor speed until i got about 200v , i was able to run just about everything off it, the main issue was though was when a relatively heavy load stopped drawing power the governor on the motor didn't keep up and you got this surge in speed hence why i ran it around 200v, so when the voltage did spike it only went up around 240v to 260v so still fairly safe for most of the stuff i was running , when i first started it up before i got tuning it i was able to generate up to the 1000v mark as for the capacitors i pretty much didn't have to change anything

Very interesting! I agree, it would be interesting to see it hooked up to something to bring it up to speed. You are correct, 60 hertz is what we have in the States.

I would love to see you do a collaboration with Jeremy Fielding over at the Fielding channel on this concept. He could possibly do all the required calculations too.

i was given the equipment from an old DRY CLEANING BUSINESS. the big dryer drum's bearing base was over 1 inch thick and over 4 foot diameter and had gussets too, the shaft was 2 inches thick or thicker. lots of 3 phase motors 220 volt and made in ITALY ! was planning to use to build a very large VAWT as i had 20 acres in montana that had one edge of the property on the edge of a very tall bluff. but got sick and ended up selling the property and scrapping out much of the equipment. here in south dakota we have a strong wind most of the time. i can get metal 55 gallon barrels for free from a business, and i still have lots of the 3 phase motors, and other scrap metals. it would be great if i could use the 3 phase 220 volt motors to make a VAWT that puts out enough DC VOLTAGE to keep a battery bank charged, maybe even hook several VAWT's in to a combiner some how. i live next to a smelly ass cattle confinement operation so nobody would complain about noise etc... as a scrapper i get lots of stuff that could be used all sorts of ways to build generators, but having the proper place to store it all is the problem!

Super video Robert. Thankyou for the upload!!!!!!

Thank you very much for explaining how the induction motor works, and how to use it as a generator. I've been trying to understand it all day but now I think the light finally came on.

Very interesting and fun tutorial on induction motors and generators. Thank you.

I Love ❤️ this man. Wishing 🙏 you 😃👍. Love from Africa 🌍

That's really awesome. I've got to look more at this.

Good info. Ive now halted using magnets on an old beefy ac powertool motor.

i was only disappointed not seeing the motor/generator get up to speed. . .otherwise excellent

Here is an example of how to calculate the capacitance needed I got this example of wiki. It goes up if you need to draw a load from the generator. As an example, consider the use of a 10 hp, 1760 r/min, 440 V, three-phase induction motor as an asynchronous generator. The full-load current of the motor is 10 A and the full-load power factor is 0.8. Required capacitance per phase if capacitors are connected in delta: Apparent power S = √3 E I = 1.73 × 440 × 10 = 7612 VA Active power P = S cos θ = 7612 × 0.8 = 6090 W Reactive power Q = {\displaystyle {\sqrt {S^{2}-P^{2}}}}{\sqrt {S^{2}-P^{2}}} = 4567 VAR For a machine to run as an asynchronous generator, capacitor bank must supply minimum 4567 / 3 phases = 1523 VAR per phase. Voltage per capacitor is 440 V because capacitors are connected in delta. Capacitive current Ic = Q/E = 1523/440 = 3.46 A Capacitive reactance per phase Xc = E/Ic = 127 Ω Minimum capacitance per phase: C = 1 / (2*π*f*Xc) = 1 / (2 * 3.141 * 60 * 127) = 21 microfarads. If the load also absorbs reactive power, capacitor bank must be increased in size to compensate. Prime mover speed should be used to generate frequency of 60 Hz: Typically, slip should be similar to full-load value when machine is running as motor, but negative (generator operation): if Ns = 1800, one can choose N=Ns+40 rpm Required prime mover speed N = 1800 + 40 = 1840 rpm.

I'm saddened and somewhat amazed how many of these videos youtube is not letting me find until they are really rather out of date. While I watch your videos 'religiously', you may notice that many of my comments are way younger than the release date. I only just now found this one through the logarithm which is interfering with them coming to me the same day you put them up.

Amazing this is very handy well done working that out

Another great an informative video my friend!

anyone here from GreatScott?

Very interesting....but that should be top secret and you give it all to us....hhhhh...very valuable information for me..thank you very much and God bless you...

Thank you for your enjoyable and informative videos! A small critique of this video, the black shirt sweater makes it difficult to view the parts you are discussing. Keep them coming!

Excellent video Robert.

This type of video will get people thinking. Even if they don't fully understand it.

Great video, incidentally this is how the Tesla vehicle can regenerate energy, also this is a Tesla invention of course, the rotor is a shorted inductor which will universally oppose any inductive force on it hence it will rotate after being in motion or with {as stated the 90deg alternate winding or start C with a centrifuge switch.} Thanks for sharing . One for the historic record.

Yes, that was of much interest. And... very... empowering. Indeed.

Your video is playing at 4:00, and as I watch, I wanted to say that I learned how to magnetize the rotor by coiling a thick Guage electric cable through the holes that are put within the much larger ones. Once you have it ran through correctly, you just add an electric charge to the cable, and then remove the cable and the rotor maintains the magnetic field. I'll share the link to the video I watched. I tried it myself on an old blower motor that came out of a evaporative cooler. I wanted to turn the blower into a wind generator. I'll bring back the link shortly after I finish the video.

I love your videos. Keep them comings.

God your doing great things.creating interests for kids adults alike. Keep going this world needs more and more people like yourself. Thanks

Great video, great explanation

Hi very helpful video, thanks. How exactly do you wire the capacitors for a single phase induction motor? Do you add them on to the existing 8 mF capacitor or wire them directly where the 2 power leads go in? My motors power box has 6 terminals. 2 for power, 2 for a resistor and 2 for an existing capacitor

Great presentations , I found it is possible also to permanently magnetize the squirrel cage with a length of 8 mm guage wire and 2 batteries in series . After this process the squirrel cage will be magnetize permanently alone.

I remember my old Electrical principles module from '86. The rotor is known as a 'Squirrel cage' rotor, It relies on induced eddy currents. en.wikipedia.org/wiki/Squirrel-cage_rotor

I can recall the 1981 great comedy, Only fools and horses with David Jason and Nycholas Lindhurst in the main roles. Really amusing indeed

I work on generators and diesel power generators and engines . A motor start assist for underpowered installations: a flywheel coupled to a gearbox to an induction motor. The system idles at 60 Hz . 1800 RPM. 1500 for 50 Hz. Gives a LOT of motor starting amps! Used to be common in industry. I still find them sometimes.Thanks for posting!

Brilliant, thanks this will save me money. Great job! Will these be able to self run if a flywheel and small motor to keep up the start RPM?

Pretty amazing. No hocus pocus here, I'd love to see a 3 phase motor do this and see the 3 phase output on an O-Scope.

You sir are amazing 👏 thank you

You have come back to my world. Although my Ioniq uses a permanent magnet (synchronous 3-phase motor) it provides excellent motor and regen for braking in the functioning of the motion of the vehicle with of course recapture of energy to the batteries. Mechanical braking is almost unnecessary,.

I really enjoy your videos, very helpful! I could use your advise regarding the induction motor. I tried to use it as generator, 2hp single phase with 2x200mq capacitors alteady inbuild. I got only 50v output

Sir I are a book of knowledge thank you for the information

You sir are amazing 👏

If you power down the generator while connected to a load the initial magnetization of the core will be zero. If that happens disconnect the load and don't spin the generator (static) and temporarily apply a "AA" battery to it. The battery will leave a residual magnetic field that will be a starting magnetic field when you spin the generator up. To help prevent demagnetizing the field put two silicon diodes in anti parallel (anode of one to the cathode of two, and the cathode of one to the anode of two) and put the diodes in series with one of the load wires. The diodes will disconnect the load when the voltage drops down to either plus or minus 0.6v and leave a tiny bit of residual magnetic flux in the generator core. The small 0.6 drop won't be a serious loss at 120/220 volts AC. The generator works better with more capacitance. You can use polarized capacitors but you have to take another step before hooking them up. You take two of the same capacitance and hook their negatives together. The negatives are insulated and not used. The remaining two positive leads are used as if they aren't polarized and can be used on AC. The capacitance rating is halved but you now have a non-polarized capacitor.

Okay. Now I understand why the alternator requires an input current to produce voltage. Hadn't made that connection before. Thanks.

The motor out of the drill isn't an induction motor. It is a brushed AC motor. Apart from that, quite interesting.

Very interesting. Thanks.

That is fascinating... ty !

Thanks for sharing. That mite be why my sear's generator doesn't work. Because a cap went bad.

I know they motors from car buffers have brushess, but they do make great generators, my test results have shown good voltage and current.

Hope you get an invite from TedTalk. That would be Terrific.

I love your channel, you are just the old guy three million doors down... a few things.. when the wind is blowing and the rotor is turning free wheeling, it extracts no energy from the air. If you load it the more it slows down the more energy you are extracting.....when you put iron in a coil you lose a little bit of energy to flip the iron back and forth, but there is a gain because the iron is more permeable to the field than the air in the coil. In the case of your perimeter of the circle idea, the greater voltage is generated when the magnetic lines of force move faster.If You go the axle to extra you have the mechanical problems you mentioned and you have a speed and gearing problem. When you decide between series and parallel in the coils, try to have just enough voltage and more current. it the source is a higher voltage than the load like a car alternator at high way speeds the extra voltage is blown off as heat. thats why a car alternator has fins all over it.

That's super cool!!!

well fox me... thanks for the explanation of the laminated steel bit

Induction moters are used as generator in places where speed/rpm is variable because it can output canstant frequency independent of rpm and depends on input frequency given at the start using a soft stater, but moter should operate at super-syncronus rpm to generate power

Fascinating stuff...

It seems this would be perfect for a vertical wind generator, as the speed of the blades is self-limiting, so if you match the inductive generator speed to the blades, it will operate at peak efficiency.

To all: For more understanding: Remember, this saying . ELI the ICE man. Where E= voltage L= coil/inductor I = current. In an inductive circuit, then = voltage LEADS current. ICE where I=current C=in a capacitive circuit E= voltage. so.......CURRENT leads VOLTAGE, in a capacitor circuit. This, should clear the idea, of 'how' a 'start' capacitor, gets the rotation going. The centrifugal switch, inside/on the motor, will switch off that starter winding, when after about the first half-second, of spin up, or so.

Tip of the day when playing with ready made motors you will need to know .some motors have allouy windings looking like copper wire . even coated the same colour . What you will find is when you try to energize and parts such as the stata or rota com it will fail . in most cases the armature will have copper wire but fields are made of allouy .metals , what the chinese do is attach 2inches of copper wire to the ends of there cleaner and washer motors with crimps hid in insulation , so if you grab the motor and clean of some insulation it shows to be copper ,. In truth this is done because of heat and currents traveling across the connections . when the com spins and brush gear make contact frequencies of 216hz will be made per second while the motor pulses on and off .The faster the spin the higher the frequency the less current drawn .When under load brush motors draw more current as they slow under load .So the crafty sods attach real copper to the fields . Now when you try feeding the motor with a voltage to create a magnetic field all you get back is just a few volts .. so take off the brushes and remove the bearings for future projects and bin it , Some washer motors have the same set up and want make a bean , so don;t wast time and check first for copper .

Works well with a water turbine where it rotates just slightly faster than synchronous speed. You can attach to local electrical power and makes your watthour billing meter run backwards for a credit. It is inherently safe because if there is a power failure, it stops generating.

Hello. I am not very electrical savy but I was wondering if a person could use the mag from a lawnmower and use a windmill to spin it and then collect the current and store it or use it to power devices? From experience one can get quite a shock from it. lol

Greetings from Alabama just needed to say that I love all of your videos absolutely great job on explaining everything brother!!!!!!

it was pretty helpful. my thing im using as a generator is a 14 pole 60 hertz ceiling fan motor(80 ohms which i assume is 8 poles and also 60 ohms which maybe 6 poles). I have a 15uf capacitor in parallel to the 80 ohm winding. it is i believe a capacitor start motor. i got the capacitor from an old generator(very very old). the fan works but by spinning it by hand(to generate), i can only get like 300 millivolts and barely any current output(i have a stepper motor as generator and it can generate like 30vac). Please suggest something i can do to improve results.

Hi Rob, I was wondering why you didn't use a three bridge rectifier? Super easy to connect three wires from the motor and the other to your load. Cheers mate.

Very interesting, but a bit too complicated for me, be good to see a very basic diagram of the set up, especially how and where the Cap is placed. I’ve got a few of those Microwave Caps and Induction motors. So I would like try it out, just a thought, is it not possible to magnetise the rotor?

Great info..

Realizing this is years later, but any chance you have a simple sketch of the circuit? inputs/outputs of the motor? Thanks! and very helpful!

Something to think about If you face a square coil to approaching magnet as the magnet passes either of the 4 sides of the coil it produces electricity but the other three sides are a waste but if you have 4 magnets passing all 4 sides you will provide full saturation of the coil world that not be the nearest maximum output of the coil?

Thank you

Nikola tesla invented the A.C. Induction Motor and, something I learned last night that I did not know, this is why the designers of the Tesla electric car named it after him because they are also using an A.C. Induction Motor to propel their cars. I always figured they just used a D.C. motor. (I watched an interview with the two designers of the car and they explained this)

Holy cow thankyou Robert I have been playing with a 3 phase motor wondering about this very thing and found even spinning it with a cordless drill at 900rpm (motor rated at 950rpm) I could only get about a 3v ac peak and was wondering if you would be able to come up with a solution, strangely I was looking at these for a design of VAWT wind turbine using a centrifugal fan to turn the motor. I added a rectifier hoping to see a result in DC but unfortunately saw no more than maybe 1v (this was over a week ago so can't remember all details) but clearly I wasn't running the motor at a high enough speed. I am also wondering whether combining this with a moped variable ratio style gearbox woul;d enable the motor to maintain speed with reduced effect of turbine speed.

I have a old washing and dryer motor with the capacitor that came with them do you think these capacitor will do the job. And would the wires be connected the same way as if it was tun off grid power

That's sort of amazing, it sounds like it's a lot better deal without magnets. Could it be made to be self powering?

an easy and quick thing to do for induction motor is to magnetize the rotor. what's needed 4 mm diameter copper wire length it depends on how big is the rotor and it has to be wound the wire all around the metal excluded the aluminum clockwise,1 battery 12v "even if i believe and i haven't tested it yet but i will, it would be better if apply to the wires 1.5 to 2 volts for about 10 15 seconds in order to have a better result at low amps let's say 1 amp top". same process to magnetize ferrite,the difference is they have different professional tools for that,home made you make it do with what you have and spending less possible!! or the same way a mechanic magnetize its tools.

Just as a thought experiment.... How would a Multi Stage Tesla Turbine with some form of gearbox, let say 3 to 1, interact with something like this. In theory, you get very high revolutions out of a Tesla turbine. Not sure how much torque this might require from the turbine, but the power output should be quite good because of the speeds that you can reach with a multi stage turbine.

I have a question! I'm looking for a simple way to make a DC to AC inverter that can match the power in a US wall socket. Can I use a DC motor to turn the rotor in that AC motor + the capacitor to generate an AC current? Specifically, can I generate 120V AC at 60Hz? If so, how much DC current would be required to supply into the DC motor in order to get that high AC power?

Thanks for the information. Would it be possible to post a wiring diagram just so newbs like me could have a visual reference on hand.

thank you