Explanation of the phase relationship between the two transformer secondary windings, or two halves of the winding, feeding a 120/240 V Single-Phase system.
At 74 years old and been working in an electrical environment for more than 50 years I have never seen a good explanation like this. Would have loved to have you as my tutor. Keep the videos coming.
the biggest issue is arrogant electricians.. the teachers (typically former electricians int he field) will want to "skip" over stuff, to appear to be "macho" to the guys from the union or for those working in industrial. He will say stuff like "I know you guys know this stuff so we can run through this part, but if you dont raise your hand". therefore making it a matter of ONE guy looking "less of a man" for raising his hand. AND DONT LET that man be a minority among a bunch of white men.. because then theres a DOUBLE whammy feeling. the white guys looking upon you as if youre stupid. this is why teachers need to be TEACHERS ... like this man is doing.
A most unusual video where the explanation was unique and a credit to the Dave Gordon. I have never seen the concept of vectors addressed to the non maths audience in this fashion with attention to detail . You sir are a credit to your profession.
But wrong conclusion.. . He failed to identify the correct Reference point, which is and has to be the Zero or Neutral point. . . . Looks as if he sort of used the paper as his reference. . . . Paper does not carry electrical current, wires do, so you have to use the correct electrical point, which is the Zero or Neutral point.
Brilliant Dave. Absolutely the best instruction I have ever seen in any venue on any subject, and I've seen a lot. I'm going to watch every one. Much thanks, what a gift you have.
Brilliant, but WRONG Conclusion. . . He is not even looking correctly at his Own drawing. . . The Reference point is the Grounded Neutral point. . . All should be referenced to the Zero or Neutral point.
Thank you for this videos! I appreciate all of your material! You have a great gift of putting the subject into terms that can be understood. I look forward to more videos in the future.
Thank you for that explanation. It cleared up in my mind how the phases work. Why it's called single phase power but we can get 2 different phases with respect to the neutral.
Thank you so much for making this video! No other video I found explained the reference for the two sine waves before, and you really helped me have a lightbulb moment.
I have asked many so called experts how a negative current could exist below the neutral and not shock you when touched. This has finally explained what they could not explain. Thank You Sir
I wanted to explain better my concepts to customers as English is not my native language and this video was absolutely outstanding. Beyond your evident electrical knowledge, it's your ability to explain and transmit that knowledge, plus the nice quick practical setup, your whiteboard and the camera job, it's what makes this truly remarkable and creates huge impact. I will be recommending your channel. Kudos, Dave. I am subscribing to keep learning ,refresh my knowledge and pick up your words & sentences!
Beautiful explanation Dave, helped me to visualize what's happening. Your explanation about the transformer coil winding direction really helped me a lot.
Not phases. We usually call them _legs_ because they are not different phases, and the legs are a metaphor for the entire secondary winding of the transformer.
Came from another video that suggested that they were not in phase. This video did an outstanding job of explaining how to think about this, specficially using the reference points. Thank you so much for this!
Mr Gordon. You do nott know how much I have lerned from your videos. You explain so easy the things and with so easy analogies and vocabulary that is very easy to grasp. As someone said I wished I could had a teacher o a mentor like you! Keep on the outstanding content!
This was a great video. Even having taken circuits courses in college, my understanding wasn't that great. Your demonstration was concise and easy to follow.
Your explanation is simply superb. I've seen and heard many discussions on this but not with this level clarity and demonstrations to illustrate the concept.
I teach automotive basic electrical, so while i come as a learner I also watch with my teacher hat on. You have a great style of delivery! Nicely done explanations. Also, since i'm used to working with some pretty large DC circuits (starters, alternators, and my house also has large 12 and 48v inverter circuits) I experienced an subconscious discomfort at how hard you were working those D cells. Lol
Got to say I've watched so many videos, and this is the ONLY explanation that I've been able to understand 220V in phase. Nice job, you should be at MIT
Your videos are wonderful. I have degrees in EE and CS but I have been a programmer in medical imaging research for most of 25+ year career (did a little engineering work in the early days). I am interested in relearning at least some of the information I have sadly forgotten over this period of time.
I'm on about the same track. EE the worked in architectural engineering for a couple years then got into comp sci (had a comp sci minor in college, and programmed during high school). I've been doing mostly line of business applications with some public facing sites. I'd like to get into something a little different though. How did you get into medical imaging?
Perfect explanation and demonstration, thank you Dave! I have tried to explain what single phase means and that split phase is like a center tap transformer used in electronic power supplies. Most people just po-po me saying "it has always been 180 degrees out of phase" and they won't change their thinking.
Wow! GREAT JOB! I have finally found someone that shows exactly what I have been saying for many years. When you try to explain this in a comment it is hard to get the point across! I have been saying that since oscilloscope is connected to neutral as common, it only looks like half is out of phase. You explained it perfectly. In phase to me is a point in time! And when someone says it is out of phase, it drives me nuts. I will be sharing this video with others.
@@davegordon6819 Thank you so very much for this video. It even surpasses your fantastic Open Neutral video. This video should be considered to conclusively shoot-down the "180° out of phase" belief once and for all. I reasoned this all out myself a while ago and have been trying to explain this (the two legs can't be additive if they're out of phase) to people, but this demonstrates it better than I can explain by far!
Thanks for explaining this. I have the delta 3 phase and did not understand how it worked. I use all of it on a 5hp pump but split off 2-120's for shop equipment.
Thank you, I am a curious, jack of all trades, master of none type of person who has always just accepted the split phase / out of phase concept without fully understanding. I understand it now. Once again, thank you.
This is a world-class presentation! People get killed because they don't see that individual 120 V branches have the same load on their own neutrals as the "hot" when running even though collectively, the neutral only carries unbalanced loads. The two sides of a single-phase panel are legs, not phases, and the use of the term should be "phased out." LOL.
Thanks Dave. I'm in my mid 60s, have a physics background (I understand electricity from Maxwell to Feynman), over-the-top experience in res. wiring and, until now, have never fully understood "split phase"! THANKYOU.
I assumed that it was 180 degree out of face, but when tried to analize vs the center tap.. I got a short circuit in my head.... but never had the opportunity to see it through an Oscilloscope to reveal how current flows between phases and the neutral at the same time..... wonderful explanation... greatly appreciated!!
Very nice description. Many others have mentioned your unusual US split phase system but not explained how it works. Thanks. It was interesting to see in your practical demo the phase to phase light still lit even though you had removed the batteries to reverse them. The phase to neutral lights had extinguished but phase to phase still lit. A nice demonstration of leakage current that you might want to demonstrate some time.
*THANK YOU* for this! I have been trying to explain this to people for a while, and this demonstration perfectly outlines everything I've envisioned and understood. The principle of number of turns is key, as that not only directly relates to voltage (transformer ratio), it also means that if "180° out of phase" were true, then 240V could never be made. Again, thank you for this fantastic complete demonstration and explanation!
Let me try to come to your page since our previous attempt went nowhere. You make the claim several times in these comments that it is utter folly to use the center tap (neutral) as a constant reference. I have one simple question I am hoping you will humor me by answering: Why is it folly to do as such in a split phase scenario, yet it is common-- standard in fact-- to use a common reference when determining phase angles in 3 phase? If you disagree that it is the standard to measure 3 phase relationships off a common neutral, please work with me on that. That would be our sticking point. If you agree with that but think there is some fundamental difference in the way split and 3 phase are measured, help me understand what that fundamental difference is.
Dave, at the beginning of the video you explained if the turns were reversed at the neutral point that it would be out of phase. It would not be out of phase, but instead it would be reversed polarity. Reversing the polarity would give you two 120 circuits and a net zero for full tap. It is how a regulator works with using reverse polarity and using the same winding to be able to raise or lower the voltage, but any single winding coming off a highline single phase will always be in phase of each other.
@@I_SuperHiro_I Yeah. Reversing the polarity is essentially multiplying the sine wave by negative one, which is the same as being 180 degrees out of phase.
