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 !!!
@@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.
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!
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.
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?
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!
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 RU-vid 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.
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 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.
🤦🏻♂️…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.
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.
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.
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.
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
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 .
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?
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 RU-vid .
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?
@@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
@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 ?
@@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
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.
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.
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!
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.
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!
Thank you, thank you, thank you. You must be famous. Never have I seen any explanation of this subject so easy to understand. RU-vid should put this video on top. Best wishes.
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
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..
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
