Understanding STAR-DELTA Starter !

You might have seen that in order to start a high power rating induction motor, a starting technique called star-delta is used. In this video, we will understand why a star-delta starter is needed, and how it is accomplished practically with help of animation.
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[@mod1959]

I am an EE Engineer and no one has ever explained this crystal clear... Can see great efforts behind this video. Congratulations.. 👏

[@deepeshgupta7356]

Bhai tu ee engineer ban gaya aur tujhe pata bhi nahi hai ki induction motor start kaise hota hai 😆😆😆,interviewer ka l@ua munh mein liya tha kya?

[@serialseatsniffer5610]

"Engineer"

[@twerktospec]

Aka a lonely man who lies on the internet

[@davehageman7513]

@@twerktospechow do you earn your daily bread?

[@aaronr5555]

I am concerned for your projects that you qualified as an electrical engineer and didn’t understand a basic motor starter until watching a KZbin video 🤣

[@rupeshkumardalavi4872]

This explained in just 6 minutes what our professors couldn't during the whole course. thanks a lot

[@rohnsteve8842]

Yeah true

[@TelekineticKhai]

The weird and sad reality of the world is that most teachers are bad at explaining things. One of those things that should have been corrected for better efficiency, but strangely isn't. They don't understand what we don't understand. Understanding is hard - it should be a field of art in itself.

[@ansar.mansar.m9519]

Ansar m sir 4pole motor 1750 rpm 36 slots and12set 2 coil motor series connection numbers diagrams send me I am very thanks too you

[@bill4all782]

My lecturers were quite good and i already understood this,however,the visuals here makes the understanding perfect

[@ZAKXOXOXO]

i think it's because this with good animated video, coz picture win a thouson word video wins more imo

[@Tuxedo2680]

A picture will always be worth more than a thousand words. If educators all over the world would explain math and engineering using clever animations like these ones, the rate of basic understanding and academic success would rise significantly in schools of all levels.

[@johnallen-bx7jp]

5 years in hvac and no one has ever been able to explain that to me like you did in this video! Much appreciated

[@tigerseye73]

As an Industrial Electrician, now retired, I learned this starter application many years ago during my apprentice training. Your video should make this very easy and clear for young guys starting out in this trade. Excellent job.

[@johndoe-bo7rx]

Don't even have to go to school for it.

[@comfortchisholm3828]

Also, I appreciate the animations as well as the pauses, that give time to process the info!!

[@sandracordoba6090]

After 5 years finally someone explains this properly. Thank you.

[@thisismjay]

you have no idea how much you helped me right now!! Thank YOU

[@mdnuralom6235]

Yeah I have no idea so don't tell me 😂😂😂😂😂

[@adehary2902]

@@mdnuralom6235 Erwiana e rrrrqquqq di Indonesia dengan tema tips 7 yg

[@suatsenoglu8441]

@@mdnuralom6235 l olll

[@suatsenoglu8441]

Llll

[@JjMn1000]

Ok

[@martyrobbins5959]

Bro I have seen tons of videos and even went to school for this. Your video is more valuable than all previous resources I have encountered. Great job man.

[@aandreoli8961]

The best illustrative explanation on KZbin I could find. Thank you

[@LucasLatrova]

BEST EXPLANATION EVER! What caught my attention was the lack of over information, It has just the mainly and essential topics. Congratulations for this work!

[@mmspkd]

Thank you very much. The most clearest explanation I've ever seen. Animation makes it the best one.

[@Ancientlaws]

Very clean and informative. I learned this as part of energy efficiency course. Good job on both the explanation and animation!

[@sumanmajhi55]

Watching this video.. kzbin.info/www/bejne/n4a2nXSPd6yFncU

[@khaledal.moghrbi4555]

I loved it

[@Obtemus]

the first clear and perfect video I watch concedering 3-phase induction motors

[@sumanmajhi55]

Watching this video.. kzbin.info/www/bejne/n4a2nXSPd6yFncU

[@sunshine7453]

This is a very effective explanation of a complex process using animation. It is a lot of work and I appreciate every second of it. Thank you!

[@amitdube13]

Excellent narration and explanation. For a Mechanical engineer to understand the intricacies of 3 Ph AC motors, this video was just superb, fantastic. Thanks & Congratulations.

[@rogermylan6528]

I love the teaching techniques of this channel. Amazing :)

[@335alien335]

Interesting video. Now it's time for a part two to explain what's missing on the contactor depicted on the left and why it's essential to physically interlock the contactors. Keep at it, you're most of the way there.

[@444mikeee]

I thought it was just me, thanks for confirming the error also. lol.. Maybe the other people didn't watch to the end of the video, to catch the last 30 seconds.

[@tusharkatti1]

That is the simplest & the most effective explanation of Star delta config i have come across yet.Good Job guys!

[@joelpagcaliwagan6588]

Thanks for the knowledge YOU SHARE and a very good presentation. GOD BLESS YOU MORE!

[@KR1SU1]

Great timing on the video! I just did the measurements of starting current in both delta and star formation on an electrical engineering lab course.

[@solidus8098]

Amazing! Mind-blowing how you guys explain things so freaking wel! Thank you!

[@muhammadzeshan4090]

That was amazing... I mean really amazing.. During all my study and career I knew the motors draw huge starting current but never knew why they do so.. Thanks to you...

[@mayurchawde3516]

The way of teaching with animation I loved it

[@Dilidjent]

The best Engineering and scientific channel on KZbin! Thank you for amazing videos: It will not be necessary for future generation to be oriented on books.

[@shinigamisama5664]

Dilidjent awesome to see someone that likes science and engineering and also Tesseract. Love them

[@benaloney]

So you're saying we need to burn all books?

[@thomaskoomson5986]

Good

[@fototoestelletje]

@@shinigamisama5664 Me too

[@chelseaveck]

Thank you very much, i've finally understand how contactor works including the star and delta connection.

[@autogps7293]

www.electricaldon.com/

[@duskolo]

One of the best engineering channels on youtube! Keep up the good work!

[@namdevchandilkar8050]

This video helped me a lot during my examination.so thank you for making such an awesome video 😊

[@NiksCro96]

You gave me such a fantastic insight how star-delta works. Many thanks :)

[@dglad4697]

Very good explanation! Loving the animations too, very accurate.

[@danieldauber8335]

The work that went into this. Outstanding job!!!

[@ShivaprasadDabholkar]

The clearest explanation of the functioning of the star delta induction motor starter I have come across. Thanks Sir

[@selfdestroyed16]

amazing... today u learn the exact working of contactors with induction motor... thanks....

[@SilentSnipest]

Who does these animations? They are amazing.

[@joopterwijn]

What program do you use?

[@abdulazizhawsah9884]

बिकेश श्रेष्ठ thank you so much for your help

[@jackbalitok3910]

I agree this was the first time I saw a technical video with such clarity of graphics and explanation.

[@youmah25]

great job

[@zeeahmed3123]

Austin Anderson these kind of animations take alot of time and effort to make

[@aldoomarmendezm5267]

I'm a Mechanical & Electric engineer student this video is very useful to understand electric control machines. Grettings from Mexico.

[@JT-xt8bh]

Awesome explanation,spent 4 hours on this and none the wiser,in 6 minutes I now understand this arrangement.

[@ValchevKiril]

You Sir deserve, to Live long and in prosperity!!!

[@abeltadesse6486]

This video Taught me more about Induction motors and contractors than 5 years of Engineering.

[@PilotAwe]

I have seen some exaggerations in my life time but this one takes the cake

[@satipsrl5207]

Contactors,contractors are other people who shots to capture Saddam Hussein

[@karanbhattt]

I can't thank you enough for the clarity you have provided.

[@javiervidoza2316]

The best explanation ever have heard. Congratulations!!!!

[@EmilianoBorghi10]

Very good explanation!!

[@AwesomeCrackDealer]

Great video, thanks!

[@sumanmajhi55]

See this video... kzbin.info/www/bejne/n4a2nXSPd6yFncU

[@faust666desrosiers]

Precise, Comprehensive and Detailed as always. Thanks for this

[@autogps7293]

www.electricaldon.com/

[@manjurilahimalek8462]

the best of all time explaination in star delta starter history!

[@WXUZT]

I wish we were taught in this manner....we would have really learned so much !

[@shyamgopal1961]

Thnku so much,,, wonderful explanation and Animation 👌👌👍👍👏👏👏

[@anjishnu8643]

Possibly the most clear and concise explanation of 3 phase connection!

[@charmonnicolaih649]

Loved the video,it is a amazing.I have so much more clarity on motors .It was very informative.Thank you keep up the good work

[@novinroy2164]

Awesome explanation. Please upload some more videos related to OPAMP.

[@guyteigh3375]

Brilliantly simple explanation. I never was quite sure about star delta starting and now it makes perfect sense. Awesome video.

[@cgerman5]

the production value on this channel is ... fantastic

[@lynsenior2979]

I can't thank you enough for this video.🙌 Subscribed immediately, hope there's more content because the explanations are so well done.

[@zabikhan5020]

many thanks from my heart I'm electrical technician i got very helpful god bless you

[@user-lx1mk6mq9g]

講解的太完美！

[@udayprabhakar6744]

Awesome explanation sir. Thank you. I am electrical Engineer myself during 1987-1991, during this period I use to study through text books only. Thanks to the computer animation, even a layman can understand the concept.

[@ProWajxxx]

As someone who is learning electricity now, in the computer and internet age, I have so much respect for you guys that only had books and teachers.

[@pshah8212]

Very very clear 1st time star and delta diagram- connection practically on the motor. Thank you very much.

[@richardfoley7754]

great video

[@albduke]

When you guys find time maybe you can delve into all of the different types of AC and DC electric motors how they start and operate. Their torque an induction characteristics etc, etc

[@terrencemackgmail]

Finally understand how an induction motor works! Thank you! Awesome!!

[@andrewlozano9473]

I really like this video. It gave a easy to understand explanation on the star-delta configuration. I feel like others try to over complicate stuff to make themselves feel smart or they just don't know how explain things very well.

[@chitmoehtet6511]

Yes I agree

[@tx9221]

Impossible to imagine is now possible after watching this video.

[@zekoaqel1243]

that must have taken a lot of work to animate , thanks for the efforts man

[@silambarasansivaperumal657]

How much time to take star to delta convertion

[@yaderbustos4901]

Amazing video explaining how to do the start up of a 3 phase motor, Thanks!!

[@cfgman9176]

This is probably the best non mathematical explanation of a 3 phase motor I have seen. ...brilliant presentation.

[@guillaume6119]

i want be enginner, your video are very good .

[@tantitan8573]

Just like gear shift, low first, then high

[@RAHUL-xy1ds]

Wow,you are heroic for making such a difficult topic so easily accessible...

[@fabriziobrutti1205]

Wow!! Really good job at explaining this concept and translating it into something more practical!! 👍👍

[@khan6718]

Just thanks

[@SunnySingh-ny2qh]

First time in my life i understand how starter and induction motar work

[@jeylful]

Fantastic graphics and explanation! Thanks!

[@animeshkarmaker6779]

Your videos are really awesome and appreciable. Best of luck to share knowledge!

[@selfdestroyed16]

please also make a video about relay used in electrical panels....

[@sumanmajhi55]

See this video. kzbin.info/www/bejne/n4a2nXSPd6yFncU

[@ata_sevinc]

The video explains the operation of the induction motor with very good animations. Y-Delta starting is also explained well, but the usual misapplication in practice is not mentioned. It is wrong to apply this method at a 400V (line-line) network to a motor whose rating is 230V for each phase. Because such a motor should be used at a 400V network if Y-connected, and at 230V (line-line) if delta-connected. Since most networks' line-line rating is 400V in Europe, it should not be used delta-connected there. If the Y-connected starting of such a motor is proper with suddenly applied 400V, that is OK, then keep using Y-connected. But in practice, such motors are started with the Y-delta method at 400V networks (line-line) in many places. When switching to delta, each motor winding is exposed to root3 times voltage, that is, with excessive current. Then the power and torque are 3 times the rating value. The user seems happy. But the motor windings burn due to excessive current within 1-2 months. The coils need to be renewed every 1-2 months. If the motor is not in continuous use such as water pumps, this time can be extended. In order to use this method properly at a 400V network, the motor's ratings must be 693V for Y-connection and 400V for delta-connection. But such a motor can be rarely found on the market. Therefore, this starting method is misapplied in many places. It is appropriate to start these motors with this method only if there is a 230V network (line-line).

[@ivanfmartinezm]

You are wrong all these motors have SERIES COIL Construction. that mean they can work with 440 volt in Delta Configuration and nothing happend, not any problem.

[@ata_sevinc]

@@ivanfmartinezm You haven't given enough information about the motor's rated voltage. The user does not have to know whether the coils are series or parallel inside the motor. The user must know the rated voltage per phase.

[@ivanfmartinezm]

Each coil support 220 volt line to line between phases so when users connect LOW VOLTAGE is a Delta connection and for HIGH VOLTAJE (440 VOLTS) IS in STAR Configuration that mean you have TWO (2) COILS in series connected to Phase Voltaje or Line to Line

[@ivanfmartinezm]

@@ata_sevinc I hope you had understood my explanation the motor never get to burn whether it can do many start operation and work properly because it has been designed for that

[@ata_sevinc]

@@ivanfmartinezm Star connected rated line-line voltage is sqrt(3) times as the voltage in delta connection, not twice. If each phase coil's rated voltage is 220V, then that motor's rated line-line voltages are 220V in delta and 380V in star connection. If it doesn't get burned under continuous operation with 380V or higher in delta connection, either the load is low or the rated voltage is stated lower.

[@AbuTaher-eh1is]

very concise and clear explanation..thank you Lesics for making all the tough things easy.

[@charlesmunyoro633]

wow. thanks guys. this clip just made my life so so so so simple. good show!

[@alexlo7708]

Those magnetic relay also has interlock connected to ensure that it never on both in the same time otherwise, Boom.

[@TheAnantaSesa]

I'm guessing that said boom threat is also a reason the contactors are in a separate box on the wall rather than closer to/on the motor case.

[@JCarey1988]

I thought there had to be SOMETHING preventing that, with how terrifying the risk of arc flash is at those kind of power levels.

[@dj6769]

alex Lo that was what I was wondering if the timer relay kept them from both being energized at the same time.

[@aymankamel7139]

I think also there should be third contractor named common in addition to star and delta contractors

[@bengunn3698]

@@aymankamel7139 Usually called the main contactor which carries the motor over load connection.I have always seen it done with three.Looking at his diagram he as missed out showing the cables bridging across the top of the star contactor without which the coils are open circuit and nothing would happen. Apart from that it all seems ok to me and does save the cost of the third contactor, as long as all interlocks are connected [ to stop both contactors operating at the same time] and the overloads are fitted it seems a good way of doing it. A different way of doing the same thing ,good to know.

[@p0k7lm]

A " star " was usually refered to a " wye " connection in my experience and learning.📐🎓⚡

[@gunawanhutapea1750]

Even though I don't have electrical background, this video is really helpful & insightful. Thanks.

[@ionelpascu1778]

Awesome job you guys. Very informative and simple presentation.

[@Tomyb15]

I'm quite confused. 4:53 Where do you connect the "returning" cable, like the neutral in our household electricity? How is the electricity flowing there? And if the point of star connections is to lower the current that's allowed to flow, does that mean the startup is going to be even slower?

[@smiley235]

Ciroluiro 3 phase motors like this don't need neutral. They return current through the other phases as the phases are 120 degrees out of phase. Think of 3 AC sine waves staggered out by a third, you can measure voltage difference between them at any point. As for the star delta starter, it will get to star speed quite quickly, then after a small delay of maybe 2-5 seconds (depends on motor size) delta contractor will pull in and it will reach full speed quite quickly, whilst avoiding the massive current draw if they had tried to go directly from stopped to delta.

[@smiley235]

Ciroluiro Also, when in star, that point where all the bridges are shorted acts like the neutral in your house. For where I live, this would be around 240V AC RMS (phase to neutral), and when in delta (phase to phase), this would be about 400V. This could of course also be a higher value on high voltage motors.

[@Tomyb15]

That's interesting. I kinda suspected about the electricity returning on the negative of the other phases, but I wasn't sure about it. In reality I don't know a thing, but I had thought about something similar but never knew how to find the answer. Say you have 2 AA batteries; between the positive and negative terminal of a single battery there is a voltage difference. But then there's also a difference between the negative of one and the positive of another. So if you connect only those 2 terminals, does electricity flow? Because intuition tells me that it doesn't 'cause the circuit isn't closed. It may be a dumb question but I don't know a whole lot about electricity, just curious :P And for the star-delta connection, it doesn't add any more time till it reaches full speed AND also prevents the huge current draw than if it was started without the star-delta? Or did I get that wrong? Anyway thanks.

[@Tomyb15]

I hadn't read that last comment. That's also interesting but complicated when put all together. Just me though.

[@smiley235]

Yes, it is hard to conceptualise electrical behavior without experience and learning. For instance in AC, you wouldn't call the neutral the negative, as each phase goes negative and positive in relation to the neutral (usually 50 or 60 times per second). In your example with the batteries (DC power), your intuition is correct, current won't flow as the circuit is open. And yep, last part pretty much correct, star-delta might take a few seconds longer to start, whilst lowering inrush current, which prevents voltage drop to the rest of the installation, and also increases the longevity of the motor and associated switch gear. If you are interested, start learning about basic DC electrical concepts, then you can look into AC theory once DC makes sense. Once you have the basics of those two knuckled down, you can then start looking into more advanced things such as electronics.

[@carlosarango7210]

Perfect till the last minute where you skipped the details of a star delta starter.

[@EpanReza]

Superb! Really helpful especially for electrical engineer student. Thanks a lot!

[@dextersiow]

As a beginner I find your videos very interesting and insightful keep up the good effort.

[@kranshy0000]

Learn Engineering the connection of star contactor missing the upper connections also the main contactor not present

[@millomweb]

Yes, omission of phase links across the first contactor are missing. No, a 'main' contactor is not needed as these two perform the function of that. What should be included is a mechanical interlock between contactors as well as an electrical one. A further 2 pole double throw contactor would be needed to reverse the motor.

[@millomweb]

@@cqb1vet Ooh, I love white boards ;) e-mail me any time ! I've loads of info - it's just not indexed - sometimes it takes years to come to the surface ! What are you doing in front of whiteboards ?

[@srujanmunnaram3183]

no one is teaching in this way...so thats The reason y iam so average....in my college no has got job in eee department bt every sir has got doctorate in this subjects.....so bettr to study in this channel of youtube rather than going to those type of colleges...

[@theeachuisge]

Exactly. I sucked back in school, because I couldn't understand anything.

[@jasonmcgary]

Good luck getting a job putting KZbin videos as schooling lol

[@aldoelec6653]

Probably because you’re grammar is sheet

[@majiddasuqi7088]

As EE I was always don’t have the clear understanding of this concept, but now I will never forget it. Thank you

[@medicineknowledg8929]

Your star and delta connection is the very good , thank you

[@debelix]

Is this still in use? Don't people use electronic motor drives nowadays?

[@89stylomilo]

bobdebelix still in use.. some people prefer this because when 1 part is broken, it does not affect other component as well and can easily be changed..

[@debelix]

I guess it's OK for very powerful motors and if you don't need soft start and/or variable speed, because drives cost a lot of money. (More power, more money).

[@Dan_Divebomb]

Actually this is just one version of an electric motor. With IGBTs or FETs you can drive it in all speeds. The Tesla Model S uses exactly this kind of motor.

[@debelix]

In electric cars they use BLDC motors with permanent magnets, not induction motors. Induction motors are asynchronous while BLDC's are synchronous motors and they generate power when breaking (to charge the battery) which is not the case with induction motors. :)

[@petarmiletic997]

bobdebelix There are many industrial applications where more complex drives would be completely unecessary and just add to the cost. Also induction motors can be used as generators, you just need to run them faster than the magnetic field. Many electric cars do use BLDC motors but the Tesla does use an induction motor. IMO induction motors are better than BLDC - motor drives are similary priced, efficiency is similar, and they don't require rare and expensive magnets. Pretty much every electric vehicle today bigger than a car uses induction motors - trolleybuses and trams, locomotives etc.

[@liamdurkin1152]

Definitely wouldn't of worked in star without links in the other side of that star contactor. No star point

[@PilotAwe]

Nice notice, i would've also appreciated a some sort of analysis how the star and delta affect current and torque, instead of just saying its smaller

[@Superior_Mindz88]

Don't know if this channel is still up but Big Thanks this puts me in a great position now in 2022. Going into motors now in school .. instructor is Not diving deep enough . So I have to get how You live and that's On the Come Up✌️

[@azizuae4789]

One of the best video on induction motor and so simple

[@villehietala9677]

Seems like that animator has never seen an actual star-delta-starter and its connections. There are 6 terminals (+protective earth) on such motor, why would anyone connect 9 leads (+pe, which is not in this video)? Then at showing the star contactor, there should be jumper leads visible at other side. Contactor wont do anything without those. And in real life, you wont just stole electricity from a side of another wire and contactors etc has been modeled to be real, so why not use connections on those to show where wires are really fixed.. And then there is the case of missing third contactor.. There's 1% of down votes, so those are the electricians watching this video? Its nice that most of whom has commented are stuck at nice animations, so probably wont be harming themselves with actual motor connections..

[@beardedsawyer6322]

Exactly my thoughts! Also, the Delta contactor was quite unclear.

[@mohamedrafi5807]

This animation is just for understanding the basic Y-D starter. If you want complete Y-D design than you should use main contactor, Mech. Interlock and push button....

[@xzzx22]

I was looking for the third contactor too. but anyway this video is for getting the main idea, not to construct the circuit. and they're making great videos.

[@firstname2072]

yep i was thinking WTF the whole time in this video lol

[@krishnakumarm.r.3042]

ville hietala - sir, they are only teaching the theory of star-delta motor working and not practical wiring. In actual wiring there is a third contactor which is the main contactor and NC -NO wiring in both the Star and Delta contactors. Please understand this is not a EEE class room.

[@him.h.1354]

first comment

[@aymanissam4878]

Himel Miah hahaha

[@Lesics]

Yah :)

[@jumjam234]

great

[@joopterwijn]

Of your commit would tribute great, this is childish, come on....

[@sidahmedakcentSidahmedLm]

Himel m. First to comment last to get laid. Awesome video btw

[@oliverstreet7704]

It’s a nice technician level instructional video. This is basic information on how a star-delta starter (or delta-wye starter) is wired. Presumably this leads to being able to troibleshoot one that isn’t working or replacing the motor with one with an unexpected terminal configuration. Don’t expect to get anywhere as an EE in an electric machines course based on this much information. Even if you confine the topic to 3 phase squirrel cage induction motors an EE also needs to be able to refer the rotor schematic to the line side, understand why the rotor bars are skewed, understand how what this video identifies as the “stator” is wound and why, understand how to limit or prevent stray current through the bearings, understand how to calculate the slip rate, starting torque, running torque and breakdown torque, understand break before make vs make before break, the difference between a contactor and a relay... and whatever else your professor introduces during this basic topic because it prepares you for more complex machines like motors / alternators with wound synchronous rotors / exciters.

[@jhonviel7381]

thanks teach

[@Aravinth-vi6fs]

Nice animation work and explanation😍😍 excellent job guys!!

[@pinoyako9830]

Bravo! This simplified, detailed and animated video is very easy to understand. Just like an Indian type of explanation but with American accent.

[@PaulWhitelock]

A great video clearly explaining the subject. Great job and thanks.

[@ducamuk]

This video is very ,very informative! I just got smarter. Thank you so much for posting. 🙏

[@asif181]

One of the best video on induction motor and Y-Delta config,, thankyou.. liked and subscribed...