Delta and Wye - Volts, Amps, & VA

[@Peace88Hi]

Thank you so much Dave. I have a degree in Electrical Engineering but never been lucky to have a professor to explain so clearly the way you are explaining this topic. I am reviewing all of your videos and relearning everything with clarity and comprehension. Thank you so much for passing your knowledge on to others to learn. Thank you again Dave !!!

[@Electric_Sherlock]

Really?! Wow. Glad you got to relearn the basics.

[@aly8848]

same here, only if my professor were this good. they never explained concepts like this.

[@RoRokenya]

You were not attentive at the time of lecture most likely. 😂

[@Peace88Hi]

@@RoRokenya you are absolutely wrong. There are lot of horrible professors out there only hiding behind unions to protect them. They barely tech well. I guess you are one of those, so you are upset about what I said and you are defending them indirectly.

[@RoRokenya]

@@Peace88Hi 😂😂 Oh no. Not defending any person please. On youthful days we may not be very keen to on some topics

[@bobblum5973]

I am glad you pointed out at the end that the value 1.73 is the square root of three. You'd shown the value earlier, but I think it's important to explain that it is used to account for the phase angle difference between current and voltage across phases. You don't need to go in-depth into trigonometry, but sine and cosine functions can help to visualize what's going on. Your phase diagram where you erased all but the two phases and added the dashed line was a good way to show the difference in potential between them. I learned all this about 45 years ago, but watched as a refresher. Well done!

[@normblanchard5199]

The square root of three has absolutely nothing to do with the phase angle difference between voltage and current. You are thinking of power factor.

[@bobblum5973]

@@normblanchard5199 No, not power factor, like in single phase current versus voltage. The voltage differences between phases and neutral in 3-phase delta and wye configurations. A quick search online for "electric phase square root of three" gave me good results.

[@Electric_Sherlock]

@@bobblum5973 there is no sqrt(3) voltage difference in a delta configuration. Line V = Phase V.

[@Electric_Sherlock]

🤦🏻‍♂️…it is not to account for the phase angle difference between current and voltage across phases. Because you only apply it to the appropriate configuration. In a delta, Vline = Vphase, so no sqrt(3). Also in a WYE, Iline = IPhase, so again no sqrt (3). You must be very specific when talking electrical. Otherwise you get people confused and spread inaccurate information. Not to mention there’s also a 30° shift that goes along with the calculation anytime you use sqrt(3), which he fails to mention anywhere in his spill.

[@bobblum5973]

Sorry if I mis-stated, I was thinking about three-phase signals in general and wye in particular. For delta it may be different, I agree, though now I want to look it up and read further. 🙂 I learned most of this about 45 years ago, and at the time it was more involving electronics than electric power, but the square root of 3 stuck in my mind.

[@michaelcostello6991]

Magnificent explanation. I think a lot of teachers do not fully understand what they are talking about and the students end up being more lost after listening to them.

[@ClergetMusic]

A lot of professors have PhDs and no training in how people learn, so they are experts in their field with poor teaching methods.

[@joshspears7016]

Please help me : I was working today and a guy on a direct crew pushed up against a closed panel 480v 3 phase and it shorted between the phases. Question: if he was in contact with the metal case while the case was touching the exposed breaker lugs would he have died ? I suspect the voltage would have traveled through the case and to the other lugs, avoiding going through him as the metal is the path of least resistance. Is my conclusions incorrect?

[@soundman2604]

Refreshing my memory here, you are one of the best explainer ever. No, flailing arms in the air or bubble head movements or tripping over your own words. Neat drawings and clear numbers and most of all you speak slow enough and clear enough to understand every word. So far, the best I have ever seen on youtube, keep up the great work!

[@jacobmartin5104]

You explain this so much better than any place I’ve seen or anything I’ve read. Thank you

[@GuiltyKit]

Been an electrician for many years, and this is probably the most easily digested explanation I've ever seen.

[@janinarichard7910]

As a BSEE and PE engineer your explanation illustrating the connectivity and formulas are superb!!! I was able to figure out the line current and voltages of this transformer on these electrical dwgs. GREAT JOB

[@earledaniels4539]

This guy is a fantastic presenter and explains technical details so well 👍

[@aaronshults8472]

Beautiful lesson. I hope you can see this. Please never stop making videos. You are a treasure!!

[@sama0314]

Ok

[@toddt6592]

I'm 40 and have just started to dulge into this type of work. I can say... from someone with very little knowledge of electricity. You do a very good job of making it as understandable as possible. Thank you.

[@galeforce21]

Thanks for the great videos !! I'm studying for my Canadian Ip exam after not having been in school for almost a decade, all this stuff is a distant memory and you're teachings are so clear and effective!

[@javiercastro8466]

I never had the chance to have a formal education, but I was fascinated by electricity and electronics and had to figure this out on my own before there was the internet, much less KZbin videos. I picked up DC in 6th grade and AC theory by 7th grade, but could never find any well written books on 3 phase power or Delta Wye configurations. I am now entering retirement age and despite not having gotten a degree, I did manage to work on some engineering level jobs in my life by just teaching myself. Thank you.

[@amirs.currim6442]

Bravo!

[@TXRoeJogan]

I’ve watched this video probably 5 times, come back for a refresher every now and again

[@rogerdodger5886]

I'm sharing and commenting so this gets more views. Thank you for taking the time to pass on your knowledge.

[@5stringpickin]

Fantastic, clear understandable explanation. You are a great teacher, thank you!

[@josephinepedersen8295]

As a mechanical engineer who should have learned/remembered this from school, Thanks so much, this and your other videos have been super helpful!

[@Airsoftgunes12345]

I'm also a mechanical engineer - and this was hands down one of the best explanations for a refresher.

[@dhimitermisha3775]

Very clear explanation , well done ! I suggest simpler than that , in either case delta or wye , winding voltage times winding current times number of windings . In delta , 480x10x3=14400 or 120x40x3=14400 in wye .

[@joshspears7016]

Please help me : I was working today and a guy on a direct crew pushed up against a closed panel 480v 3 phase and it shorted between the phases. Question: if he was in contact with the metal case while the case was touching the exposed breaker lugs would he have died ? I suspect the voltage would have traveled through the case and to the other lugs, avoiding going through him as the metal is the path of least resistance. Is my conclusions incorrect?

[@lawrencecohen1619]

This is a wonderful, concise and easily understood video. The only thing missing is the shared pot of coffee.

[@wilassguess]

Best presentation explanation I’ve come across yet. Thank you.

[@03ceezy18]

Really well explained! I was overthinking the turns ratio and the step down in voltage from my course lectures.

[@ElectricRob]

Great video Dave (even if it's 4 years ago - still the same!). Wanted to add a little trick we use in the industry to further simplify those power formulas - note that for example on the primary side, the 480V x 17.3A x 1.73 formula - if you take the line to line voltage of 480V and multiply by 1.73 you get 831, so the easy formula is just Amps (per phase) x 831. Similarly on the secondary side, it simplifies down to Amps (per phase) x 360, since 208Vx1.73 is 360 (which also is the winding or line to neutral voltage of 120 times 3). Makes the math super simple. Cheers!

[@carlubambi5541]

Thank you for what you are doing .I am master electrician and recovering from CoVid and have that brain fog issue .This is fantastic review .Learned this in high school and trade school .we need more of this on KZbin .

[@joshspears7016]

Please help me : I was working today and a guy on a direct crew pushed up against a closed panel 480v 3 phase and it shorted between the phases. Question: if he was in contact with the metal case while the case was touching the exposed breaker lugs would he have died ? I suspect the voltage would have traveled through the case and to the other lugs, avoiding going through him as the metal is the path of least resistance. Is my conclusions incorrect?

[@carlubambi5541]

@@joshspears7016 .How did that happen ?.That's considered assault and in the work place it's very much a criminal charge .NO journeyman company owner or workers of any kind should get away with that .Including horse play .Electricity always takes the shortest path to ground or the path of lower resistance .You can still get a shock on a delta/wye system through capacitive coupling but remember this ,the shock isn't the issue all the time, it's that arc flash which is 5 times hotter than the surface of the sun that can kill you for sure !Most don't survive the arc flash !.My Foreman almost lost his life pushing in a bus duct switch which was shorted internally on a 1200amp 600 v 3 phase bus duct system .He was pushing in a 100amp 3 phase switch for a step down transformer .He Burnt his hands and his face ,had to get skin grafts .Got fined by the Ministry of Labour and ESA Electrical Safety Authority .He had to go to court . Lucky to be alive .Remember this ,you don't have to look for electricity ,it will find you .Same rules apply with guns .Treat every gun as if it's loaded ,treat every wire as if it's live and follow all the rules for working on and commissioning equipment .Everyone life is at hand

[@joshspears7016]

@carlu bambi he was on a different crew, but i heard he was just putting on stickers on the outside the first hinged Door of panel. The main cover was still on when he pushed the sticker against the cover some how it touched the exposed lugs on the breaker. flash was contained within the panel. so the ark is the main concern? Not electrocution as he was not directed exposed to inside of the panel only one hand made contact with the outside cover ?

[@carlubambi5541]

@@joshspears7016 if he had both hand s on the panel there could be a chance of a potential difference but not likely because the steel cabinet is a far better conductor .Just remember you only need a few milliamps to flow through your heart to mess you up pretty bad.I survived somewhere between 347 and 600V .Someone wired a lighting fixture neutral to ground and energized the TBar .I went up the ladder to look for a 120v tail for a receptacle and someone had coiled up another 347v lighting tail with a 120v receptacle feed .Let's just say it's like a shot gun going off beside your head .Had flash burns and a burn on the tip of my finger .Lucky .Felt like I was kicked by a horse .Took out the 100amp feed breaker on 3phase 600v 347 lighting control panel .the circuit was on a 20 amp breaker and it blew a 3 inch hole in the duct work

[@joshspears7016]

@carlu bambi interesting story the dangers of electrical trade. I'm still learning. Hopefully I will be here many more years

[@bobcat4820]

You are Amon Lubiano here in the Philippines,,,,glad to see your channel sir,,,BIG BIG BIG SALUTE❤

[@spencersmith791]

You explained this AMAZINGLY

[@ronmurphy2069]

Another great performance. Thank you Dave.

[@eisenhauerca]

Great info for anyone either new to the electrical field or seasoned vets. Thank you. “An electrician who knows it all is a dead electrician.” -My Journeyman

[@kosmokritikos9299]

This reminds me of technical college, but also of a job interview after graduation. In the interview I was asked where I could have learned one of the topics I was embellishing on. When I mentioned the college I had graduated from, he said, "They don't teach that there." When I asked what he thought they did teach, he replied, "You know, like how to hold a screwdriver or charge a battery for a power tool." I ended the interview there.

[@aresp2707]

Mind officially blown.🤯 Watching again to pick up the pieces.😷 Your directions are simple enough, but all of this is new and so foreign to me coming from a plumbing background.. I still would like to know about all of these processes though. Thank You again for another highly informative made simple to understand video.

[@muhammadmustaghas4437]

Best lecture I ever see in such a simple and excellent way..

[@VTdarkangel]

I'm an electrical engineer so this is all an old hat to me, but this video is one of the best I've seen to clearly and concisely describe these basic calculations. I'm going to send this to my technicians. They have a basic understanding of AC power calculations, but they weren't taught much about 3-phase and where it is different from single phase. Very well done.

[@Michaelmuq]

Love your delivery 😅😊. Thanks for the great lesson Prof. Michael from Yonkers, NY (nyc)

[@isaacjtorres]

Boom! Dave just dropped the mic when he multiplied 120v by 1.73. *and everything seems clearer now* big thanks DG.

[@stephenchienjo3283]

Hi sorry for asking, but kindly please tell me where the 1.73 comes from

[@nishanthasubasingha6284]

I am electronic technician having with basic electrical knowledge....,this is greate for me.,.... thanks

[@abrahamjaime9417]

Gordon, you’re an amazing teacher! We miss you at the program.

[@Tbellman85]

Thank you very much sir, for the brief explanation. please share your knowledge to everyone...

[@jsv.2932]

Ok, yeah, third video I`m watching from this man and almost never it has been so easy to click the subscribe-button.

[@motionsick]

Thanks man your videos were a huge help on a job I did earlier this year. Now I'm learning more about higher voltages. ⚡️ ⚡️ ⚡️

[@benrasmussen9878]

thank you. I'm getting 480 into my shop , and a step down transformer for stuff that runs on lower voltage. This helps me understand what is going on.

[@amirhosseinfarajzadeh7777]

Hi , i really enjoyed this video you explained it very clear and comprehensive, wish you the best

[@macmen007]

Excellent basic 3-phase step down tranformer explanation.

[@subramaniamarumugam2433]

Champion. Liked your presentation very much 👌🙏🏼

[@TWTH]

Masterful presentation. Just like @peace88Hi, I too have an EE degree, but I decided it was time to properly teach myself some of the things that I merely stumbled through in the past. If I am able to explain it to my 10-year-old kiddo, I will know that I really understand it. Thank yo so much!

[@earleharris1999]

NO ONE has explained this better than you! I went to Naval Nuclear Power School (NNPTC) to be a Nuke Electrician... They used the WI-DE memory aid, and I'd still trip :) up on transformer math. Current-ly :) studying to be a RC System Operator and reading it straight from the source didn't help me either. Thank you!

[@bigbrother9531]

50 years ago, learned the same Wye-I, D-E. Nuke school taught me a lot fast.

[@chicagoflipsters6772]

I want to say thank you so much of your work.

[@Lazdinger]

This man has a gift for teaching.

[@khosafx8365]

My former instructor at the jatc! Nice channel!

[@matthewellis3004]

Might take me a few more times to digest this one. Thank you for explaining.

[@johnguilbert1349]

Excellent explanation on this topic. Thank you for the great video!

[@loucnc]

Thank you for refreshing my memory.

[@bobbyh6293]

Thank you for this knowledge! Houston Texas

[@quabot]

This is very much like the instruction I got in the navy, which has been the best training I’ve experienced thus far.

[@OSAS726]

You are so spot on correct!!! I love the way the Navy explains things. Have you ever studied the navy electrical electronic training series(NEETS)? You are so right about the way the Navy explains technical details. They assume that everybody is an idiot and explains it to them in a way that they can fully comprehend the most complicated concepts.

[@quabot]

@@OSAS726 Thank you. I studies NEETS in the early 90’s but I had also graduated from the Mk-15 Phalanx C School.

[@GeorgSimonOhmsLaw]

Splendid explanation. Clear as day.

[@Baghdad2001]

Thank you Dave! You are the best

[@rigosandoval282]

Thanks Mr. Dave Gordon do You Are Best Of Best.

[@michaelschweizer4772]

Thanks, was always curious the calculations involved with three phase.

[@mortenlund1418]

Thank you, thank you, thank you. You must be famous. Never have I seen any explanation of this subject so easy to understand. KZbin should put this video on top. Best wishes.

[@Steven19990]

Awesome explanation. Thanks Dave!

[@Shanks344]

Very well done, very thorough. Thanks for the video

[@TripleTRanchAndSawmill]

very good explanation and presentation

[@ysfhammou7768]

Excellent teachings Dave Thank you

[@losttribez186]

This was so easy to understand thank you for sharing

[@dominicg818]

Very good explanation of PIER in xfmrs.

[@mrbuck5059]

Wish I had this guy as a teacher in the tech school I was at. He didn't say "particular deal".

[@ganeshirodi7517]

Thanks Gordon much appreciated.Just wanted to know incase if there is a phase failure or line failure on the delta side,what happens on the secondary side , how can I detect this fault on the secondary side of the transformer

[@OrdinaryDude67]

We (in the USA anyway) get our 120V for receptacles from a center-tapped delta secondary, not a wye secondary. This is why Line to Neutral = 120V and Line to Line = 240V and not 208V.

[@davegordon6819]

Thanks for engaging Bill. In my area of the country (USA) the center-tapped delta secondaries are on their way out and the three-phase commercial services are generally wye systems - either 480Y/277 or 208Y/120. Also, all the three-phase transformers I have installed in the past couple decades that are to feed receptacles have been 120/208 wye configuration. I know there are differences regionally and by facility type, so that may be the difference in our experiences. I have another video that compares 120/240 single-phase, 120/208 three-phase, and 120/240 three-phase: kzbin.info/www/bejne/rn69nH5_atefm8k

[@OrdinaryDude67]

@@davegordon6819 Hi Dave. My comment was really geared more towards residential services and not commercial/industrial, where we expect to find 120V to neutral and 240V line to line. In my commercial/industrial experience I’m with you 100%. Every dry-type transformer I’ve installed has been a delta-wye with a 3-phase 120/208 secondary.

[@davegordon6819]

@@OrdinaryDude67 Perfect. Sounds like we're on the same page. And by the way, keep up the drumming :)

[@Alotgame930]

I still install a lot of open Delta Banks in San Jose Ca .. I work with people from all over the states and they state the same, why most electricians say that the 120/240 three phase banks are going away if we still install them. Actually we still install Close Delta banks that are 120/240 and use a Power Leg( stinger/ wild leg) to create that 3rd phase in new construction.

[@rolandoservilla2251]

Very accurate explanation

[@marshallstephens7356]

Great explanation and editing! Thanks

[@TheCompton1963]

Love these videos. He is such a great teacher!!! 🧑🏽‍🏫

[@musoangelo]

The 208 Y is very common on work boats because you can get the 120v without a transformer. The problem is that after a few decades of boat engineers wiring things up, many of them don't make sure that each 120 leg is in balance with the other 2 legs.

[@0my]

What happens? What usually fails first?

[@pengwang1785]

Finally I know what is underrated video

[@thehobbit2422]

Dear Sir, Would you tell me the resistance of the Delta circuit between Point A and Point C when all coils are 10ohms? thank you 🙇🙏

[@tedlahm5740]

Sir Question. The pictured Transformer is a 3 phase delta wye? If so am i correct that the delta has no neutral back to the substation? thank you.

[@brianlittle717]

A lot of our buildings are supplied with only two phases but we run 3 phase equipment on them. Two phases on the pole and two transformers. The large transformer has a center tap neutral and the smaller transformer just puts out 120 volts. Every 3rd breaker is a high leg with respect to neutral. Do you have videos on this? I’m struggling to understand how a 3 phase compressor can run on this because it’s missing a phase and the rotating magnetic field is broken.

[@jcolterh]

Thank God you made this video.

[@markgarrett8814]

Thanks and that really explains a lot to me but I'm confused about something like where I work the power company just installed a new 300 kva padmount transformer and I noticed on the front cabinet that it says it's a 7200 volt primary and 277/480 volt secondary but how are we getting 120 volt service from this unit and it's the only transformer supplying our shop so please explain? Thank you

[@hassanmansoor5629]

Very good explanation

[@Hertzultra]

That was enjoyable.. I was a bit confused for a spell looking for the root 3 which I remembered from my City n Guilds L3 17th Edition but sadly never got to use..

[@BlueButtonFly]

Its fun to watch this stuff when you're not cramming for tests at 3am. Also low stress when its way outside your field lol.

[@tomaszwota1465]

Wait, parentheses don't change anything here in the last equation...?

[@orangaharris640]

My only question here is how did you get the 10a current ,you just made it up , which calculation do I use to get the line current if I don't have the winding current

[@discoveria6219]

I just have one question. If we assume that the wye is connected to a unbalanced grid is the grid connected to the delta then unbalanced too? I just wondering how MV grids are balanced and LV grids are not balanced but are often connected with a Dyn transformer

[@duchche]

The best explanation, thanks boss

[@tedlahm5740]

I have no idea where the 480 volts to feed the DELTA primary winding COMES FROM? 7,200 on usual each phase distribution system?

[@isaiahmullin7123]

I have a Simple question. I understanding most of the video, I just want to know how did you know to times the winding current by 1.73. Is that a law for all three phases transformers or just this example.

[@treyrmason]

Why do you multiply by square root of 3 a second time when calculating the power?

[@evalindaniceta3267]

EV charger company says I can't use 480V,delta has to be Y, but they require no neutral. i have 208,3 phase y service so i used transformer in reverse,could only find 75kva,delta to y transformer. I don't understand why the 480V without neutral is any different, Joe

[@nyechewoke301]

Excellent explanation.thank you Pls can you put more light on the graphic representation

[@johnmarkmesiona1221]

Even if I'm a Filipino I understand his very very accurate explaination

[@melalbano6351]

Thank yuo Professor Dave.

[@jolyonwelsh9834]

In this example you would use a15 KVA 3 phase transformer because that's the next commercially available larger size assuming that that is the only load you have on that transformer.

[@mhd230289]

I would have been lucky if I had professor like him. 👍

[@oliverwijesooriya2067]

Very excellent explanation

[@jameshodierne4808]

Love the way you teach. 👏

[@S-MKim]

Maybe it's easier to write VA = 3 * Vw * Iw, where 3 is because we have 3-phase identical circuits. This will also end up to VA = sqrt(3) * V_line * I_line.

[@mahatmadoo2566]

As pure as the azure sky of deepest summer.

[@عمرصبحيضيف]

can you tell me how many electrical power rise due to increase in number of phases ? or in another word, what is the relation between number of phases and power?

[@TheNathanBorgman]

Thanks for your awesome videos

[@sanjeevbhogal6818]

add a section individual currents for if single phase loads used on all phases to neutral, i assume should not to be more than 40amps

[@rhysfastiggi4345]

Where did rhe 17.3 come from? Sorry I missed that explanation.

[@azarudeen463]

Mr.dave I just want a simple explanation about that constant value of 1.732 where it does comes from, what do we have to study to understand about those 1.732 value, I have seen many videos regarding this though still I am in confusing please can you explain me

[@DougGarrett-xb1vh]

Vector geometry and 30/60/90° triangle.