I was under the impression that the white wires were the safe ones. I was 19 years old up on a twelve foot ladder working in a commercial building. I was working the fluorescent lights hot because it was a problem shutting them off. So 10 feet off the ground I learned that the white wires are extremely dangerous. Fortunately I didn't fall or get injured. After that horrible shock from 277 volts, I was really having second thoughts about the trade I was getting started in. I'm a retired 68 year old electrician and by the grace of God, still able to talk about it.
Older guys (my gdads age) used the saying “only touch one wire at a time and you’ll be ok” which is absolutely untrue. A break in the circuit path neutral or hot is a place to get hurt.
dude, a grounded conductor only has zero volts until it is disconnected from the neutral bus. onces it is disconected the voltage increases to that of the ungrounded conductor, in your case 277 volts, when you touch that and then touch ground you become a big assed human resistor to ground. current flows......that hertz real bad.
I am a senior technician, self-employed in the PCB manufacturing industry. Back when I was struggling with the difference between ground and neutral, I came up with an analogy using water that helped me better understand. Imagine you had an upstairs laundry room. Of course, there would be a drain in the middle of the floor just in case the washing machine sprung a leak. But, in normal use, the water in the washing machine would go down the intended path through the drain behind the machine. The drain in the floor acts the same as a ground. It's not an active part of the washing machine plumbing but if necessary it can carry the water away to avoid flooding the downstairs. The drain behind the machine acts as the neutral because it is intended to carry the water away in normal operation.
I wish all electrical tradesman were as cool and down to earth as this guy and willing to teach... I would've learned so, much faster and much sooner in my career.
Unfortunately it’s because a whole lot do not understand theory. They can still be a decent electrician or installer but will struggle with troubleshooting and teaching.
We had fires in our office cubicle walls back in the 1990s due to excess neutral wire current. The cubicle outlets were spread among three 120V phases with a shared neutral wire. We all got office computers that had non-linear power supplies: their AC inputs were bridge rectifiers feeding big capacitors. AC input current only flows in spikes on the peaks of the AC voltage to charge the capacitors. In a 3 phase configuration with balanced resistive loads, there is zero neutral current; the current flows (push and pull) cancel. In our configuration, the current spikes on the AC voltage peaks occurred 120 degrees apart, so there was no cancellation. The neutral wires were overloaded and caught fire. Facilities opened up the circuit breaker panels and used an infrared scope to look at the neutral wires to find the ones that were hot. They then ran new dedicated circuits to feed the computers on those wires.
Nonlinear devices (power supplies, VFDs, and others) contribute harmonic distortion onto a power distribution system. Certain orders of harmonics called triplens (includes the 3rd, 9th, and others) do not cancel out even in a balanced three-phase system. Triplens specifically sum on the neutral. A three-phase system with a large percentage of nonlinear loads (depending upon the type of course) may see triplens. Where applicable, this means more heating on the neutral which is even worse the more unbalanced a three-phase system becomes due to connected single-phase loads. Assuming no other means of mitigation is employed, a smart engineer will oversize a neutral for this reason (perhaps 150% or even 200% compared to the phase conductors). This is also a reason to specify a distribution transformer with a K-factor rating that is selected considering the total percentage of nonlinear loads.
Back in my first year of apprenticing I was working with a journeyman who sent me to find an open neutral in a junction under the house and when I found it and asked him to turn it off he said what do I gotta turn it off for you’re just fixing the neutral connection…trusting him I started pulling on the connections and got a nice zinger.
Voltage is not the same as current. If you have an open neutral it is no longer a 0 volts wire. It's now energized to 120 because there's no path back. At which point it's technically not a neutral. Anytime you touch a wire under load that has current running through it, if there's less resistance through your body to ground than there is in the wire you will get a shock.
For what's it worth, I actuallty liked that you didn't have the "schematic" drawn already. Not sure why, I have seen you draws these dozens of times, I guess it just gives me time to process it things and get my mind in the right frame for what you're about to discuss.
I would agree with you for apprentices and people new to the trade for people with experience most of his topics are as basic as they get like 1st year stuff
I believe it was Einstein that said that you can’t be sure that that you know something until you can explain it to a 6 year old. I am pretty sure Dustin can explain these fairly complex concepts to a 3 year old . Half of the enjoyment I get from watching this channel is watching Dustin put his excellent communication skills on display. Dustin you have a great gift to be thankful for . Thanks for sharing it with us!
glad you you understood it, maybe you can explain it to a six year old and get him to explain it back to you in six months time just to be sure he understood it and retained it.
@@cameron6803 it would help if he would get rid of all of the extra parts while explaining neutral, and actually explain why there is a wire in the middle of the coil.
This is absolutely incredible, I remember watching this 3-4 years ago just out of curiosity for the trade. Seeing this channel grow and continue to educate is amazing, I really appreciate the time and effort put into this. I’m a chef, not even an electrician and I watch most of these videos.. so thank you!
I was a chef for 20yrs, then covid happened, went on furlough, did a little off the books landscaping to supplement UI.. Now I’ve been an apprentice electrician for a year and already make about an the same as the most I ever made cooking. And I have a lot of weekends off now😁 At a small-ish company doing commercial and industrial only, I can definitely say on average this trade is far less physically and mentally draining than cooking. And the money is sooooo much better. There’s a shortage of electrical workers nationwide. Just putting that out there. Sometimes I miss the kitchen but overall I’d say switching to this trade is the best career decision I’ve ever made
This is probably one of my favorite videos you've done. Good job! I liked how you got into the more scientific way of explaining your point, but keeping it simple enough for the beginners and apprentices. Keep up the good work. Thumbs up!
Dustin is so good that one of my teachers in my trade school just used his videos to fill up the entire class period on Zoom. Maybe because he was lazy, who knows but the fact that these videos are so educational and informative that they can be used as real in-class school material is amazing and shows its quality and value haha.
For me, the way he talks is like he is talking to a friend rather than a superior. He is able to maintain the attention of the younger generation and keep things interesting.
Sounds like most trade schools. They suck. Most are filled with instructors who are looking for a little extra cash and don’t really care about the student. People like this guy and myself actually care about educating the trade one student at a time.
Sounds like a lazy teacher, you pay to be taught, the video should be homework, & review, & expand on in class! The video should be used as a supplement and watched on your own time, very lazy teacher! But yes his lessons are very good
Electrons do flow, but very slowly maybe 10cm/hour at 100V, what they actually do is provide a conducting path that allows an electromotive force to transition between each other. It’s a convention to aid understanding that says electrons flow.
MFn' Dustin! I'm a JM trying to graduate to a Master. Huge difference between people who can be laid out at a construction site and run a 100' of 1/2" conduit for an 8 hour day and an electrician that actually understands how things work and arn't just following builder plans. I chose to go to service department years ago. I learned all I needed to know about how buildings are built. In service you really gotta study and understand how things really work. Love your videos! Thank you good Sir.
I knew the answer, but watched anyway because I like your teaching style and enjoy watching. A topic you may want to consider is (for the general public) how to select the proper size generator or inverter to meet grid down needs. I find myself giving the same advice in comments over and over, and would rather just refer them to a good vid.
I also knew the answer and i'm from Australia so i figured i'd watch to see if he gave the correct answer as so many sparkies in Australia fail to understand these fundamentals I agree, overall he did a good job
I been watching your vids since I was an apprentice and they helped me a lot to get my Journeyman’s card. Now I’m on my way to get my masters and I’m sure I’ll pass it.
As a practical point to novices doing wiring. Of course whenever possible turn the power off before connecting wires. But remember if you touch between two neutrals you can become a load. In effect you put your body in series with that circuit path. So the assumption that some people have that "the white wires are safe" is bs.
Don that is so true! When I was a lineman guys would get careless handling neutrals, especially during storm trouble. Get yourself between an open neutral or a tool between an open neutral and you can find out the hard way.
I don't know the NEC codes of today, but I recall an old tale of a plumber being electrocuted working on a water meter because the main neutral was bonded to the house side of the water pipe and not the street side. True story? I have no clue.
Your diagram is wrong starting at 13:40. You’re trying to demonstrate two loads connected to the same leg in parallel, but you’re using the EXACT same circuit diagram as before but only with different colors. The color of the wire does not make it behave any differently. To demonstrate this correctly, both loads would be connected either to the top or bottom of your secondary, the way yours is drawn.
Dad was a master electrician. Damn near short of an electrical engineer. He could build a circuit board to do just about anything. He taught me a ton but there is so much more to learn. He always laughed when I got (oh and I still do), confused on three way switches. I also remember him talking about balancing out large starting loads like motors or pumps. He said at the start of the motor it’s at its least efficiency. If you could (forgive me I can’t remember the exact terminology) balance the startup of the motor, you would save money in the long run on your electric bill. I asked why there isn’t a balancing device built in. He said it comes down to cost. He passed in 2019. I have so many questions now. I almost became an electrician. I missed the apprenticeship by one year. They never offered it again at GM. THANKS! I enjoyed the lesson.
Sorry to hear about your dad, I lost mine in January of 2020. Big motors in plants use “soft starts” to prevent massive in-rush current when starting the motor. I installed an “Easy Air” kit on my home AC unit which does basically the same thing and allows me to utilize a much smaller generator to run my house on during hurricane outages or others. It’s Newton’s laws of motion that make a motor difficult to start from a stand still and uses a LOT of power for a very short time. Starting it up slowly (a few seconds) uses much less and is easier on the equipment.
Fun Fact, the balance and cancellation phenomenon is used in Pro Audio to neutralize electromagnetic interference on XLR audio cables. They're "Balanced" so that what you hear after amplification is actually the imbalance. If you plug a stereo audio feed into an amp through a balanced connection, you instantly get a karaoke track, since the instruments are rarely centered on the feed, but the main vocals are - the voices just "disappear". If you've ever had issue with the audio feed on a TH-cam video and others report it is fine, you are hearing the digital version of this.
Though you’re on the right track, that’s not entirely true. This would only occur if identical doubles of the vocal track were 180° out of phase, panned hard left and right and summed to mono. But the principal that, similarly to electricity, speakers are incapable of pushing and pulling at the same time.
No, if L and R are identical, i.e. voice in the middle, L minus R will completely cancel the vocal and anything else that's fully centered. Discovered this when I was 10 when I connected each speaker's minus wires of our stereo system together but not to the speaker ground. It was so cool to hear the instrumental version of my favorite records. Now they put a lot of stereo reverb making full voice removal harder to achieve unless you use AI techniques.
I wish my college professors were this good at explaining electrical theory when I was in engineering school. Your videos would have been a game changer for me back in the day! Nice job.
Agree, about college professors, most can't teach. I'm an engineer with a mechanical engineering degree. I fully understood everything he explained. Not so much with professors.
If I may add my 2 cents to this tutorial: 1) In a Branch circuit, where you have a Black, White, and Green, technically the White is not called a Neutral. The correct term is the Grounded Conductor, and there is current on it, because the current has only one path to get back to the Source. 2) In a Single Phase system, as you would find in a Residence, where you have (L1), (L2) and (N), the Neutral is there to carry any unbalanced load between (L1) and (L2). In a perfect world where the distribution panel was perfectly balanced, there would be no need for the neutral. However, since you have both 120V and 240V appliances in the home, then the Neutral is needed. To simplify the " PUSH-PULL" that Dustin talked about, it is important to remember that in a Single Phase system, (L1) and (L2) are 180 degrees out of phase with each other, meaning that when (L1) is at +180 degrees, (L2) is at -180 degrees, so when their currents meet up on the neutral, they basically cancel each other out, if their numbers are the same (+2A) and (-2A). (See Kirchhoff's Current Law)
Σ IIN = Σ IOUT. Kirchhof's First Law, conservation of charge. There. Now we have a gen-U-whine formula (if simple) and I'm sure there will be some EEs tying themselves into little knots pretending it doesn't apply.
Better bone up on AC circuits vs DC circuits because in an AC circuit you are dealing with Impedance, not resistance. As soon as your load has anything other than pure resistance (incandescent lamps) there's phase shift between voltage and current and Power Factor comes into play. Think multiple devices that present reactive loads from motors, fans, ballasts and power supplies. Sure, laws of charge conservation still apply, but are your ready to do the math? With a low Impedance EARTH connection bonded to the Neutral buss in the panel how does that affect what he says? Does what he say about overloading the neutral connection (center tap) from the utility being of concern make sense? It didn't make any sense to me. What about branch or sub-panels? Remember, this is AC power in a 3 wire 2 branch single phase L1-N-L2 120/240V configuration.
@@hbmike47 1) " Better bone up on AC circuits vs DC circuits because in an AC circuit you are dealing with Impedance, not resistance. " . . . . . . . . . . . There is Resistance in AC circuits as well. Impedance = Resistance + Inductive Reactance + Capacitive Reactance 2) " As soon as your load has anything other than pure resistance (incandescent lamps) there's phase shift between voltage and current and Power Factor comes into play. Think multiple devices that present reactive loads from motors, fans, ballasts and power supplies. " . . . . . . . . . . . A circuit with mostly Inductive Loads will cause the Current to Lag the Voltage by 90 degrees. A circuit with mostly Capacitive Loads will cause Current to Lead the Voltage by 90 degrees. A situation like this will cause the Power Factor to be less than 100%. However, these conditions are found mostly in Commercial and Industrial Power Systems, not in Residential. That being said, Phase Shift and Power Factor does not change the PUSH PULL narrative that Dustin spoke about, and the fact that current does flow on the Neutral in certain conditions. The point remains that Single Phase systems are separated by 180 degrees, and 3 Phase Systems are separated by 120 degrees. 3) " With a low Impedance EARTH connection bonded to the Neutral buss in the panel how does that affect what he says? " . . . . . . . . . . Connecting the Neutral Bus to EARTH puts it at the same Potential as the Ground/Earth, which is zero. There is no voltage on the Neutral, but there is current. If you put a Voltmeter across Neutral and Ground wires in a circuit, the meter will read zero.
@@hbmike47 " Does what he say about overloading the neutral connection (center tap) from the utility being of concern make sense? It didn't make any sense to me. ". . . . . . . . . If you are referring to the portion of the video at about 13:41, he is describing a situation where you have 2 circuits from the same Phase, (L1), essentially sharing a neutral. Because the circuit "Hots" are from the same phase (L1), there is no cancelling of any unbalanced currents, instead they add. So if one circuit had 3A on it, and the other had 5A on it, you would have a total of 8A on the Neutral going back to the source.
It would have been a little easier perhaps if the phase plots of the voltage sources were shown too. This would also help explain in 3 phase Y, that the neutral carries the delta current, and how by phase, each leg will return a portion of the others current.
Thank You for another great video. It is difficult explaining a lot of electrical theory. It's really a pain in the butt explaining it to an electrician who kind of has their own theory. This one in particular seems to have been taught to a lot of Sparkys that I have worked around in a rather rigid way. So many of them will swear that two loads that are, say 5 amps each, will perfectly balance out and no neutral current will flow. Every one of them that I challenged to remove the two connections to the neutral bus and tie together then use any two fingers to complete the circuit back to the neutral bus, hot, just plain refused. Finding out how much they knew about WHY was revealed when I just asked them to explain the whole thing to me. Most of the time I was just told to take a hike, journeymen, dunno why most of them are so . . . stiff. Every time that I 'had my bluff called', I explained it with Ohms Law and showed the phase differences. I also would ask them why the neutral was there if it wasn't used.. I ALWAYS said that there is theory and there is practical use. They are rarely EXACTLY the same. Kinda like explaining how to drive to someone on paper, the finesse that is required in practical use is a bitch to explain on paper. Background: Retired after 30yrs as electronics tech in a facilities management department. I worked with two master electricians, one was educated in Germany and came to the US, the other has master tickets in five states. These two were very interested in learning more about electronics and I wanted to know more about power & distribution. We were a pretty cocky crowd and we loved a good problem. Open minds, required in service work.
Light bulbs ? All a light is -is resistance between to connections. It not matter voltage , lights still work on all volts. You can not test voltage by lights. Must be by a volt metter for volts or a amp probe for amps and a hertz counter for hertz. Hertz is very important , it the speed of the volts and watts on material by the second. Usa is 60 hertz per second as south east asia and asia and middle east is 50 hertz per second. It ok to run a transformer for 50 hertz per second in a 50 hertz per second area . But not run a 60 hertz tranformer in a 50 hertz area. The 50 hertz core is thicker than a 60 hertz core so the curent can move slower on the thicker core , but can not move to slow on the core that the core made for the size of hertz travels over it. The slower the travel equals the thicker the core must be so it not melt.
Ive been a lineman for over 10 years and I have to say I like where your going with this presentation. Its hard to grasp all the intricacies involved with electrical theory and after all it is just a theory. The best way I have found to explain the neutral in regards to a 120/240 service is it neutralizes the unbalance between both hot legs. If the panel in the building always had equal load on both legs the neutral would not be needed. When I troubleshoot an open neutral to determine if its on our side or in the home. The easiest way is to clamp an amp meter around the whole service. If the neutral is good it will read under 1 amp regardless of the load. Because current going opposite ways cancel out in the meter.
As a long time educator, my compliments on a well illustrated and commented presentation. The "on the fly" illustrations were logically and graphically informative, and well explained. You get A for this assignment.
You should do a video on 240v circuits that don’t use a neutral. For instance a well pump. How it doesn’t need a neutral because it’s 240v only. That’s something that took me a minute to wrap my head around as I was learning.
And then there's devices that use 2 phases, a neutral, and a ground, like electric dryers! The heating element is powered by the 240v, but because the socket provides neutral, things like light bulbs that illuminate inside when the door is open can be normal 120v bulbs because it just grabs power from one phase and neutral.
@@Lierofox it’s kind of silly that a lot of dryers also require a neutral. If some of the controls and control illumination/screens require 120v, they could engineer the dryer with a control power transformer inside to get 120v control power off the supplied 240v circuit.
I remember working for a college radio station about 50 years ago. We always made very sure that the loads were balanced on both sides of the neutral, both to make sure that the neutral was not overloaded and to keep any transient noise in the audio equipment (vacuum tube days) down.
Oh my! Taking me back to the beginning. Critical circuits would have trimming resistors. Amp tubes in the final would have inductive trimmers. Fortunately some tech from years gone by would have made notes in station maintenance logs so those could be preset with no power/low power.
@@thedillpickle100 - And you always installed a bleeding resistor on the pot capacitors. Once they overtightened the resistor leads and ended up with an open, which they then didn't test. So, when checking to be sure that the capacitor was fully discharged, we ended up with an arc-welded screwdriver (after a rather spectacular flash!).
For me the easiest way to always remember that "yes, current does flow through the neutral" is that any two-pronged plug won't ever work when plugged into an outlet that's missing its neutral wire connection. Half the outlets in our apartment are wired so horribly (swapped hot/neutral, missing neutral, no connection at all, etc) that it was a guessing game when I moved in. I wish I'd picked a different unit but this one's lease had already begun so I had no choice...
That was an amazing explanation, I would only add one small part. At the transformer, the neutral creates the 120v by having the return path directly in the middle of the 240v transformer wires. And, explain that between the red and the white, you get 120 differential volts, but between red and black you get 240 differential volts. At any rate, that was an amazing explanation and I'll do a better job now of planning circuits in the panel of most used circuits so that the most used circuits are better balanced in the panel.
Really an excellent explanation! Important to understand for multi-wire branch circuits as an explanation of why the hots need to be on different phases.
This would be a helluva lot simpler if you just show the two wave forms on a graph. The user could see that the troughs intersect at zero, and the peaks are the same magnitude and different polarity. This graphically shows the math, which equals zero along the whole line.
I was kinda thinking the same thing. I'm only halfway through the vid, so maybe he addresses it better but it seems like showing the pushing/pulling that the two balanced loads are doing, resulting in no net change in electrons in the neutral bar, would better explain why there's no current on the neutral.
If the neutral is balanced (cancelling out), does the current flow across the other hot wire? That's what I thought he was showing but I'm not sure about the bulbs becoming a part of a 240v circuit etc ...
The neutral wire is often confused with ground wire, but in reality, they serve two distinct purposes. Neutral wires carry currents back to power source to better control and regulate voltage. Its overall purpose is to serve as a path to return energy.
Actually positive wires carry current back to the source. Neutral is for AC. Therefore the current goes back and forth. Often, neutral is connected to say the frame which is then grounded.
Thank you for this explanation it's been a question that I've wrestled with for the same reasons you said it aggravated you as a helper. This style of information presentation is excellent for those who did not have formal education in AC theory, or has taken AC theory but decades ago and cannot remember.
I LOOOOVE this explanation. It neatly lays out the concept of how current travels on single split-phase systems and cleanly explains WHY the neutral feeder will usually show very little current flowing while neutral current shows in the neutral wire going from the load to the neutral bar. It also explains why shared neutrals in both single-split-phase system need to be carefully thought out so as not to overload the neutral wire to the point of burning it up. I don't believe shared neutrals in a residential setting are common to begin with. A continuation on this subject in a follow up video that explores three-phase commercial systems would be fantastic as shared neutrals seem to be incredibly common in commercial settings.
Question, (I'm fairly new to electrical) the diagram at 16:43, is this possible to wire? The hot from one phase connected to the hot of another phase with say a light bulb in-between. Will this work or be a fireworks show?
@@brandondill4234 Theoretically, you could. But why would you want to do that? Lamps are designed to run at 120 V and if you were to wire two 120 V lamps in series, you get 60 V across each lamp. That means both of the bulbs will shine dimly or if they’re LED, they may not shine at all. If one bulb were to burn out, the other would also stop working. To get both lamps to shine as bright as their designed to shine, you’d have to essentially run a new 240 V circuit. Therefore, it is unrealistic to have this sort of circuit in a residential setting.
@@mikejohnson3873 If you wired across the 2 hot phases you would be able to run a 240v rated device. I understand this is possible in the US if your installation is set up with the correct sockets etc. I have heard mention of this on other videos but had not fully understood how you could get 120v and 240v until I saw this video. I am from the UK where we have 240v single phase domestic wiring in which the neutral carries all the return current back out to the street. For 3 phase commercial systems each piece of equipment would take all 3 phases and would usually have balanced loads (with minimal neutral return current) so sharing neutrals would be less of a problem.
Nicely done. Would be of interest if you mentioned the consequences of an unbalanced load with a poor neutral connection and maybe some mention of the sine waves on the two phases that causes the push / pull effect on the neutral.
This was great, and I thought was going to address a confusion I have...almost did, but then didn't. I think someone else commented on this, regarding lots of time spent on the balanced load, but not enough on the imbalanced load. I get the 8A back through neutral, but I can't figure out how this is tied to ground at the same time. Arg, electricity is freaking magic as far as I can tell. Keep up the great work. I love this channel.
At the service entrance to your house (at the main panel) the ground and neutral are bonded together. This is the one and only place this bond occurs per the National Electric Code. This is done so that if a current carrying conductor (phase or neutral) touches ground, the stray current has a low impedance path back to the source which will allow a circuit breaker to quickly interrupt the fault. In a perfect world, current never flows on a ground. Think of the ground grid as a safety/backup path which stray current can escape on back to the source (instead of through a person for example). Neutral conductors are designed to carry current, unlike a ground. Think of a neutral as the normal/intended return path for current to flow back to the source.
Correct. The neutral and ground are tied together. I used to intermingle the wires until an inspector made me separate them. However, both are connected to the same place, which I pointed out. Never had a problem either way.
Nice presentation. I'm not an electrician, but have studied electrical theory out of interest, and the key fact that I took away from basic electrical circuitry a few years ago, was simple "the neutral carries the unbalanced portion of the load, back to the grid". During this presentation, I was waiting,...waiting,...waiting for your example,...and sure enough,...10a - 2a = 8a going back out to the grid !! Thanks you for such a thorough demo !!
Did you just break down Ohms law, power calculations and the physics of electricity in under 25 mins AND manage to squeeze in a rudimentary Thévenin’s equivalent problem for good measure?!? I believe you just did. Very well done sir. (*starts slow clap*) On a serious note, you should consider teaching circuits at your local college of engineering. You would be a breath of fresh air for all the aspiring EE’s, AE’s and ME’s.
@@joem6859 My two profs I had for my electrical classes/electives for my aerospace engineering degree were fantastic. But... they did seem to forget that we didn't remember 100% of everything previously taught to us about electricity. lol
@@neogator26 I somewhat agree with the other poster that some of his explanation is incorrect. I'd say he's definitely wrong regarding the neutral "canceling current and waves" because of opposition. That is not happening. The neutral carries half-cycles only. First, in a "positive" direction and then in a "negative." So, unbalanced current on the neutral is either flowing into the transformer or away but not flowing both directions at the same time for cancellation.
@@j36606 I'm not sure which specific explanation you're referring to, but I definitely disagree regarding "current and waves canceling in the neutral." That is definitely not happening in a single phase system..
The video seemed cut short a bit. Would have loved for you to spend a little more time on the flow in the neutral when you have unbalanced 120V loads between L1 and L2 and also touch on what would happen to the voltage of L1 and L2 if the neutral to the transformer was lost when the 120V loads were imbalanced. I know the answers, but would drive the point home while reiterating the importance of torquing conductors properly.
There was a house fire across the street from my house one time. The fire department cut power to the burning house and inadvertently opened the neutral to my house. The effect was expensive as I looked back and my house was very bright because of the unbalanced load now running through the lights. I lost a sump pump, a transformer controlling the thermostat for the furnace and a tv that night. This video is excellent and right on the mark. Any comments regarding getting shocked while working on a neutral are just moronic, what are you doing touching a circuit with the power on? You have no way of knowing if the 240 circuit is running balanced. You cannot touch a neutral with power on.
Thank you for all these great presentations - as a mechanical engineer (from FoMoCo) decades ago, I am learning a lot from your productions (or forgetting a lot from my age). I agree with fellow viewers that it is better when you draw your presentation as you give explanations as it allows the "students" to follow your mind process instead of being "flooded" with a complex diagram to start with. BTW, what kind of interactive whiteboard screen are you using? Thank you again, Ciao, L
I thought the electrons didn't so much flow through the medium as vibrated back and forth and it was the electro-magnetic field that delivered the current to the load.
I think when electricity is taught it is treated like the flow of water as a basic understanding. A physicist has a deeper understanding of magnetic fields etc.
@@fornife5004 Yes, precisely. Molecules of water leaving the pump outlet, traveling through the closed loop, and then returning to the pump inlet. It's a good analogy for a mental picture and for basic understanding. But, it's only an analogy..
This video and explanation is incredible!!!! Thank you, thank you Dustin!!!! These videos are a treasure to everyone who's trying to create a place for themselves in this world!!! This is true solidarity brother!!! I've always asked my teachers to explain some version of this...I probably wasn't asking the question the right way, so I never really got an explanation that was satisfying. I've done AC Theory and we've calculated balanced and unbalanced loads - I can do the math without too much trouble, but the "why" of it all never clicked until now! The electron and field/wave canceling each other out makes total sense, and the idea that the current will travel back on the neutral to get to the opposite pole completely makes sense now. Thank you!! Please, please explain why there is no current on the grounding conductor when there is current flowing on the neutral when the load is unbalanced?
Except it's partially wrong. The "electrons and waves" are not "canceling each other out." During unbalanced loads, the neutral carries only half-cycles, first in one direction and then the other. Current is not flowing in opposing directions on the neutral wire. In the balanced circuit, the neutral wire is completely irrelevant. The two lamps are simply in series with 240v across them..
Thank you. I have spoken with a few electricians who did not understand this. "How come a meter shows zero potential to earth if there's current in the neutral" is what they say and can't get past. One thing, electrons hardly move in alternating current. They travel an extremely short distance one direction, then return to the starting point when the cycle switches.
@@GH-oi2jf I find it interesting that you jumped on my misuse of a term, and ignored the claim I made that so many professional electricians don't just use an incorrect term, they have a completely incorrect understanding of how alternating current systems work. I said voltmeter to refer to a multimeter. You are aware that multimeters have an Ohm meter, a voltage meter, AND an amp meter? I am not an electrician, never have been. I worked in a hardware store for years and dealt with electricians who came into the store. I made it a point to ask all electricians the same question. I asked because I had heard people say contradictory things and I wanted to understand what they meant. 'What does the neutral wire carry?', I'd ask. Only one guy said anything other than, "It takes the current back." I'm no electrician, as I said, but if a wire only carries current in one direction, we are talking about DC, not AC. To be fair, I never differentiated between the neutral wire in an individual 120 volt circuit inside a building, and the neutral coming from the transformer to the meter/panel. Also, to be fair, none of the electricians I spoke with did either. If they thought my question only concerned the middle wire from the transformer, they would have said it carries the current for both the red and black circuits, which alternate directions at opposite times from each other. They would have then pointed out that equal, opposing, currents cancel. I never heard any of them say that.
Who are u not to not have the highest respect for Tesla ? So high it can’t go anywhere more . He’s probably in the top 5 smartest man to ever walk this earth, ur over here learning his work and u don’t have the highest respect for him who are u ? Don’t worry about who I am cause I’m the guy fucking ur mom
More importantly than pre-drawing it, you need to have set a background color that isn't the same color as the neutral! I get it, you want to use the standard wire colors, cool. But the very very white wire on the very white background doesn't work.
OMG!! I have wondered for years why the neutral bar in a panel wasn’t hot!!!!! I always understood why the neutral may be hot at a switch/outlet. THANK YOU!!!
I always understood why the neutral may be hot at a switch/outlet... oh yes? There obviously ought to be a neutral present in a socket outlet or an appliance isolator, or a spur outlet... but in a light switch (at least in the UK) there ought not to be a neutral... The neutral wire, at one time black, now blue, is used as a switched live, flagged / identified with a piece of red insulating tape... Most of the time...
Bro, that diagram you made showing that while the push and pull is happening on each phase, the neutral is experiencing the same thing, but in one conductor, therefore cancelling the current... Sometimes it just takes one person explaining it in the right way for the brain to understand and loads of other stuff falls into place. Thank you for that
Awesome Job! As a systems engineer for 30+ years No EE has ever been explain it this well. I especially like the implication of an unbalanced load and why my HVAC has to be 240VAC
3:22 point of clarity that most people don't understand about the flow of electricity. The electrons move, you are correct, but the electrons only oscillate in a finite distance and don't actually flow or move any appreciable distance. It's the wave form around the wire that actually flows and creates what we know as electricity. I'm oversimplifying it and don't really understand it 100% but thought I would point that out.
I just found your channel. You're a bad-ass teacher. This video taught so many things that a conventional educational video wouldn't even know needed to be explained.
One of the most impressive things to me about this video is that it takes 23 minutes to give the simple answer that is given in exactly one second between the (spoiler) 4:23 and 4:24 mark.
Nice. Nice to see you added the fields and discussed about them. They are a growing significance in PCB Design and Higher Speed conductors as well. Thanks !
Just come across this channel and found the explanation very clear. As an electrician based in the UK you wouldn't think this would be too relavnt but we have three phase installatons running at 400 to 440 volts and Balancing the Phases is an important safety factor ias all the phases combine in a single neutral cable and badly balanced phases could cause an installation failure or a FIRE! Your maths uses diffrent symbols. In the UK Ohms law is U=IR, the U standing for Voltage Source while V is Voltage potential. Never mind, I gave up at short tons, long tons and Metric tonnes. Just so long as we all understand each other !!!! 🙂
A few fun facts somewhat related to this: 1) In most sparsely populated rural property power is delivered in high voltage buried cable from the power pole to the step down transformer by the electric meter. In my case is 7.5kV single phase via a unground coax cable. From what I infer and research it is called single conductor despite it has the aluminium center core and a outer conductive shield, the shield does not carry the return current. Instead, the earth does despite of its high resistance which is feasible because of the high transmission voltage. This scheme is called single-wire earth return. 2) The step down transformer converts this single high voltage hot leg of 7.5kV down to two hot legs of 120Vac with one shared neutral. The return current of the primary winding travels via earth back to the substation. 3) Power generation stations and the power transmission out of them do not use a neutral because they is done by 3 phase. 3 phase delta has 3 hot legs and no neural. 4) While most residences use only 1 phase AC, they are derived from any one leg of the three phases. Because of this, a 3 phase wye power conversion must be involved. The return current on the
V Sohn. You are wrong on many aspects of your comment. Old underground cables used to have the neutral exposed, which, over time decayed. Newer cable has the neutral jacketed. Nowadays, most distribution circuits are a Y system, meaning they have a neutral. The neutral is a solid connection hooked to the Xo bushing on the low side of the transformer. All 3 phases and the neutral are hooked together internally in the transformer. On a delta system, there is no return or neutral wire. These systems are dangerous, due to the fact you can literally ground one phase in the system and it will not trigger any protection or relaying on that circuit. Delta systems are not preferred due to the safety factors compared to a grounded Y system.
@@kenchiison4570 The thing is smart people always be aware what they don't know, and the opposite think they know it all. You are seeing things from under the rocks that is the universe you perceive. Read my comments more careful as why I think delta three phase is use for long distance transmission. Delta transmission for thousands of mile requires 3 conductors, while wye requires 4. It does not take Einstein to figure out which one to choose. Neutral and ground is not a high power very long distance (as often interstates) electricity transmission requirement. Neutral and ground is a local last mile, if not last hundred yards thing. Tell us what is your professional credential. I am not a linesman, but I am a EE despite high power and electrical distribution is far from my expertises.
@@maestrovso .If you're worried about cost, you would just convert to DC and only have 2 wires. Look at your transmission structures. Up on the very top. Usually 2 static wires up there. Used for lightning protection and sometimes have a fiber optic cable in them. Usually tied in to the substation and a pole ground at each structure. Even if it's a delta. You can have a 480Y or a 480 delta. The equipment will function the same. Which one would you prefer?
@@kenchiison4570 You are so out of your depth that it shows. Please when you see those high tension transmission line steel towers next time count the number of cables on them. If there are three they are delta. delta and wye both are user for electric grid, and they both have their uses. I am talking about power grid distributions that is tens of thousands of volts. Like I pointed out, you view of the system is imprisoned in your little sphere of your myopic view.
@@maestrovso No 5hit Sherlock. 3 conductors but there is still a static wire above, usually. The point is, whether it's delta or wye, it usually has a static wire above for protection, and or, communication.
I think the biggest thing that confuses people is taking that all “electricity” is current.. hence the confusion of current source versus voltage source stuff like that.. once people get just the basic idea of what voltage actually is compared to what current actually is, i.e. talking about fields, versus the flow of electrons, makes everything so much easier to understand! Getting beyond that comparison to water the most people are taught to compare it with, and have that stick in their head. Makes actually learning and understanding stuff a lot more difficult. You have such a good balance of bringing in people that I’ve only worked in the field, as well as people that might be engineers, it’s a really good balance and I appreciate that very much!! We definitely need more of this in electrical, HVAC, etc. etc.
Current is the real physical parameter of electricity. Technically, there is no voltage. The final form of Maxwell's equations has no voltage in it. Now this doesn't mean that the concept of voltage isn't useful--it's incredibly useful. But current is the key.
Well delivered info. The drawing done as you explained it is the only way to do it in my opinion. Electricity is one of those things that is difficult to grasp cause you can’t see it but you helped clarify. Thankyou thankyou. Keep it up, well done. Liked and subscribed!!
Bro you actually explain stuff so we’ll, and with your board drawing and explaining at the same time, It is VERY helpful for me Personally to understand Thanks just subscribed
Great explanation to the topic. Makes me absolutely stop adding circuits to my house until I see how it applies to determining where and how to add a circuit.
Even I need to watch this few more times maybe a thousand thousand spectacular learning session. Recently I've been questioning the common side of just a small 24 volt circuit which led me to this great demo of how current close in a home
I reallly love the way you explained everything in this video.. i remember when i was learning i could never understand this because my teachers had a difficult time explaining it in a way everyone understood. I am so bad at explaining how Electricity works to someone that is new and teying to learn cause i makes sense in my head just cant put it in words. You have a true talent at explaining Electricity
a beautiful explanation. it solved my problem to use a single 12/3 wire for kitchen microwave and kitchen coffee maker on two different outlets without causing overload on neutral. cool. thank u.
This video was excellent. It's remarkable how many people have worked in the trade and never understood this concept. Years ago I worked in the Electrical-Mechanical shop of a large university. Only a couple guys in the whole place new this concept. I learned this when I was trying to install an electric water heater. NOW, think about 3 phases and 480 VAC. That jazz really messes with peoples minds. Add to this I have seen guys who could explain some of this but could not install a water heater, properly. Another thing that baffles the masses is that a VOM does NOT measure electricity flow; it measures the voltage differences on conductors. It's a wonder why our grid even works at all. Sometimes I think I live in a third world country. Keep up your good work.
Now I understand why there is a neutral on a 220v circuit, potential path for unbalanced loads (unequal current usage). For current to flow back to the transformer, the legs have to give and receive the potential equally, the neutral is for the unequal potential. Got it, ty
Very awesome video.very educational for someone that knows a little about electricity but you really laid it out perfectly with your drawings.what a great lesson.keep the knowledge coming.👍
This gentleman is a good teacher. Another good explanation of the North American split-phase power delivery is a video by Engineering Mindset. As far as does current flow on the neutral, it has to; otherwise there wouldn't be a circuit.
That is eye-opening. Thank you for this. Now I have to let it soak in and mull it over. Lots of new info and different ways to think about things I thought I already knew…. You are a great teacher.
This information would’ve been awesome 25 years ago when I re-wired my entire home from attic to basement… To know that people are still running air conditioners off of Knob and Tube is amazing 😳.. There was even 12/2 wire connected to it under floor boards… What a mess….
So that's what balancing circuits is for. I've wired 5 of my own homes and never really thought this way. My next remodel I'm going to use this information, thanks so much.
Thank you ! This was amazing. I'm being trained to become an apprentice and this was very enlightening. I'll share my notes with my classmates and direct those who speak english to this video.
I was under the impression that the white wires were the safe ones. I was 19 years old up on a twelve foot ladder working in a commercial building. I was working the fluorescent lights hot because it was a problem shutting them off. So 10 feet off the ground I learned that the white wires are extremely dangerous. Fortunately I didn't fall or get injured. After that horrible shock from 277 volts, I was really having second thoughts about the trade I was getting started in. I'm a retired 68 year old electrician and by the grace of God, still able to talk about it.
@McNea goodmorning...ahh do you like hamhocks or neckbones with your collard greens 🤔
Older guys (my gdads age) used the saying “only touch one wire at a time and you’ll be ok” which is absolutely untrue.
A break in the circuit path neutral or hot is a place to get hurt.
dude, a grounded conductor only has zero volts until it is disconnected from the neutral bus. onces it is disconected the voltage increases to that of the ungrounded conductor, in your case 277 volts, when you touch that and then touch ground you become a big assed human resistor to ground. current flows......that hertz real bad.
A grounded conductor would mean it's grounded wire, correct? Implying it has a charge, but still it's a ground wire.
just a joke: This is why you pay attention in physics class.
I am a senior technician, self-employed in the PCB manufacturing industry. Back when I was struggling with the difference between ground and neutral, I came up with an analogy using water that helped me better understand. Imagine you had an upstairs laundry room. Of course, there would be a drain in the middle of the floor just in case the washing machine sprung a leak. But, in normal use, the water in the washing machine would go down the intended path through the drain behind the machine. The drain in the floor acts the same as a ground. It's not an active part of the washing machine plumbing but if necessary it can carry the water away to avoid flooding the downstairs. The drain behind the machine acts as the neutral because it is intended to carry the water away in normal operation.
Makes a lot more sense than this overcomplicated video..
@@MF-kr4hfif you ever want an over complicated answer, ask an electrician
What an awesome analogy 👏
Your lesson shall be passed down through the ages.
hot is ungrounded because its bringing electricity in neutral is grounded because its bringing it back. that sound right?
I wish all electrical tradesman were as cool and down to earth as this guy and willing to teach... I would've learned so, much faster and much sooner in my career.
Many are, it’s just that the loudmouth types are usually the lead man.
Facts
Still can and still are brotha! Never stop learning!, but i get your point for sure, didnt start in the filed until i was 28 to 29 yrs old.
Unfortunately it’s because a whole lot do not understand theory. They can still be a decent electrician or installer but will struggle with troubleshooting and teaching.
Learned more about electrical in two vids than talking to more than 200 electricians. Thanks for the solid work man.
We had fires in our office cubicle walls back in the 1990s due to excess neutral wire current.
The cubicle outlets were spread among three 120V phases with a shared neutral wire. We all got office computers that had non-linear power supplies: their AC inputs were bridge rectifiers feeding big capacitors. AC input current only flows in spikes on the peaks of the AC voltage to charge the capacitors.
In a 3 phase configuration with balanced resistive loads, there is zero neutral current; the current flows (push and pull) cancel. In our configuration, the current spikes on the AC voltage peaks occurred 120 degrees apart, so there was no cancellation. The neutral wires were overloaded and caught fire.
Facilities opened up the circuit breaker panels and used an infrared scope to look at the neutral wires to find the ones that were hot. They then ran new dedicated circuits to feed the computers on those wires.
Nonlinear devices (power supplies, VFDs, and others) contribute harmonic distortion onto a power distribution system. Certain orders of harmonics called triplens (includes the 3rd, 9th, and others) do not cancel out even in a balanced three-phase system. Triplens specifically sum on the neutral. A three-phase system with a large percentage of nonlinear loads (depending upon the type of course) may see triplens. Where applicable, this means more heating on the neutral which is even worse the more unbalanced a three-phase system becomes due to connected single-phase loads. Assuming no other means of mitigation is employed, a smart engineer will oversize a neutral for this reason (perhaps 150% or even 200% compared to the phase conductors). This is also a reason to specify a distribution transformer with a K-factor rating that is selected considering the total percentage of nonlinear loads.
Get in between a neutral splice and you'll find out REAL QUICK...!!! 😳💥⚡
yea im not doin that again
Back in my first year of apprenticing I was working with a journeyman who sent me to find an open neutral in a junction under the house and when I found it and asked him to turn it off he said what do I gotta turn it off for you’re just fixing the neutral connection…trusting him I started pulling on the connections and got a nice zinger.
It will bite you
Espically on 347 volts ,line to neutral , you don't want to get between the hot and neutral . canadian is 600 volt line to line .
Voltage is not the same as current. If you have an open neutral it is no longer a 0 volts wire. It's now energized to 120 because there's no path back. At which point it's technically not a neutral. Anytime you touch a wire under load that has current running through it, if there's less resistance through your body to ground than there is in the wire you will get a shock.
For what's it worth, I actuallty liked that you didn't have the "schematic" drawn already. Not sure why, I have seen you draws these dozens of times, I guess it just gives me time to process it things and get my mind in the right frame for what you're about to discuss.
100%
This part
@@tylerrcasement what is Dustin Teaching 🙏🙏🙏
Agreed. I'm not an electrician but as a homeowner that fixes/improves things it helps me to see how it all goes together.
@@kevingray8616 Hi
Electrician U is easily the best source of info for Electricians on TH-cam. I always recommend this channel to the Apprentices on my job sites.
I would agree with you for apprentices and people new to the trade for people with experience most of his topics are as basic as they get like 1st year stuff
@@juliovalencia4948 Which is the point. I've been in the trade for over 35 years and I still like listening to him.
Thanks so much, that means a lot!
@@ElectricianU I learn lots here also. Was taught wiring at 10 years old, by a engineer- neighbor. You add to that every video.
To each their own
I believe it was Einstein that said that you can’t be sure that that you know something until you can explain it to a 6 year old. I am pretty sure Dustin can explain these fairly complex concepts to a 3 year old . Half of the enjoyment I get from watching this channel is watching Dustin put his excellent communication skills on display. Dustin you have a great gift to be thankful for . Thanks for sharing it with us!
glad you you understood it, maybe you can explain it to a six year old and get him to explain it back to you in six months time just to be sure he understood it and retained it.
I don’t understand this 😭
@@cameron6803 it would help if he would get rid of all of the extra parts while explaining neutral, and actually explain why there is a wire in the middle of the coil.
Really? I think it's horrible!
I swear you are a lot better explaining material than college professors … keep going brother … wish to see more valuable videos
This is absolutely incredible, I remember watching this 3-4 years ago just out of curiosity for the trade. Seeing this channel grow and continue to educate is amazing, I really appreciate the time and effort put into this. I’m a chef, not even an electrician and I watch most of these videos.. so thank you!
As an electrician who fell in love with cooking later on in my life. Thank you!
I was a chef for 20yrs, then covid happened, went on furlough, did a little off the books landscaping to supplement UI.. Now I’ve been an apprentice electrician for a year and already make about an the same as the most I ever made cooking. And I have a lot of weekends off now😁
At a small-ish company doing commercial and industrial only, I can definitely say on average this trade is far less physically and mentally draining than cooking. And the money is sooooo much better.
There’s a shortage of electrical workers nationwide. Just putting that out there. Sometimes I miss the kitchen but overall I’d say switching to this trade is the best career decision I’ve ever made
Lol...
Good for you, sport.
@@bradleywillis1654 yes. It's a simple trade and they are spoilt and over paid. So enjoy the money while it lasts, sport. Things are changing....
There’s a higher demand for us then ever but yet we’ll make less money in the future. Only in ur world, sport.
This is probably one of my favorite videos you've done. Good job! I liked how you got into the more scientific way of explaining your point, but keeping it simple enough for the beginners and apprentices. Keep up the good work. Thumbs up!
Dustin is so good that one of my teachers in my trade school just used his videos to fill up the entire class period on Zoom. Maybe because he was lazy, who knows but the fact that these videos are so educational and informative that they can be used as real in-class school material is amazing and shows its quality and value haha.
For me, the way he talks is like he is talking to a friend rather than a superior.
He is able to maintain the attention of the younger generation and keep things interesting.
Dustin should be teaching trade school. His teaching skills are amazing.
Sounds like most trade schools. They suck. Most are filled with instructors who are looking for a little extra cash and don’t really care about the student. People like this guy and myself actually care about educating the trade one student at a time.
Sounds like a lazy teacher, you pay to be taught, the video should be homework, & review, & expand on in class! The video should be used as a supplement and watched on your own time, very lazy teacher! But yes his lessons are very good
Also, omissions are dangerous. This is dangerous.
Electrons do flow, but very slowly maybe 10cm/hour at 100V, what they actually do is provide a conducting path that allows an electromotive force to transition between each other. It’s a convention to aid understanding that says electrons flow.
MFn' Dustin! I'm a JM trying to graduate to a Master. Huge difference between people who can be laid out at a construction site and run a 100' of 1/2" conduit for an 8 hour day and an electrician that actually understands how things work and arn't just following builder plans. I chose to go to service department years ago. I learned all I needed to know about how buildings are built. In service you really gotta study and understand how things really work. Love your videos! Thank you good Sir.
I knew the answer, but watched anyway because I like your teaching style and enjoy watching. A topic you may want to consider is (for the general public) how to select the proper size generator or inverter to meet grid down needs. I find myself giving the same advice in comments over and over, and would rather just refer them to a good vid.
I also knew the answer and i'm from Australia so i figured i'd watch to see if he gave the correct answer as so many sparkies in Australia fail to understand these fundamentals
I agree, overall he did a good job
Great idea! That would be an awesome video! Also a classroom style theory lesson like this on OHMS would be awesome!
I been watching your vids since I was an apprentice and they helped me a lot to get my Journeyman’s card. Now I’m on my way to get my masters and I’m sure I’ll pass it.
That's great to hear - good for you!
As a practical point to novices doing wiring. Of course whenever possible turn the power off before connecting wires. But remember if you touch between two neutrals you can become a load. In effect you put your body in series with that circuit path. So the assumption that some people have that "the white wires are safe" is bs.
Been there done that. Learned fast
Don that is so true! When I was a lineman guys would get careless handling neutrals, especially during storm trouble. Get yourself between an open neutral or a tool between an open neutral and you can find out the hard way.
Also why code doesn't let you put two neutral wires under one stud at the panel.
I don't know the NEC codes of today, but I recall an old tale of a plumber being electrocuted working on a water meter because the main neutral was bonded to the house side of the water pipe and not the street side. True story? I have no clue.
@@smitlag that’s not a code thing. That is a requirement from the manufacturer of the panel.
Your diagram is wrong starting at 13:40. You’re trying to demonstrate two loads connected to the same leg in parallel, but you’re using the EXACT same circuit diagram as before but only with different colors. The color of the wire does not make it behave any differently. To demonstrate this correctly, both loads would be connected either to the top or bottom of your secondary, the way yours is drawn.
Dad was a master electrician. Damn near short of an electrical engineer. He could build a circuit board to do just about anything. He taught me a ton but there is so much more to learn.
He always laughed when I got (oh and I still do), confused on three way switches.
I also remember him talking about balancing out large starting loads like motors or pumps. He said at the start of the motor it’s at its least efficiency. If you could (forgive me I can’t remember the exact terminology) balance the startup of the motor, you would save money in the long run on your electric bill. I asked why there isn’t a balancing device built in. He said it comes down to cost.
He passed in 2019. I have so many questions now. I almost became an electrician. I missed the apprenticeship by one year. They never offered it again at GM.
THANKS! I enjoyed the lesson.
Sorry to hear about your dad, I lost mine in January of 2020. Big motors in plants use “soft starts” to prevent massive in-rush current when starting the motor. I installed an “Easy Air” kit on my home AC unit which does basically the same thing and allows me to utilize a much smaller generator to run my house on during hurricane outages or others. It’s Newton’s laws of motion that make a motor difficult to start from a stand still and uses a LOT of power for a very short time. Starting it up slowly (a few seconds) uses much less and is easier on the equipment.
Fun Fact, the balance and cancellation phenomenon is used in Pro Audio to neutralize electromagnetic interference on XLR audio cables. They're "Balanced" so that what you hear after amplification is actually the imbalance. If you plug a stereo audio feed into an amp through a balanced connection, you instantly get a karaoke track, since the instruments are rarely centered on the feed, but the main vocals are - the voices just "disappear". If you've ever had issue with the audio feed on a TH-cam video and others report it is fine, you are hearing the digital version of this.
Though you’re on the right track, that’s not entirely true. This would only occur if identical doubles of the vocal track were 180° out of phase, panned hard left and right and summed to mono. But the principal that, similarly to electricity, speakers are incapable of pushing and pulling at the same time.
No, if L and R are identical, i.e. voice in the middle, L minus R will completely cancel the vocal and anything else that's fully centered. Discovered this when I was 10 when I connected each speaker's minus wires of our stereo system together but not to the speaker ground. It was so cool to hear the instrumental version of my favorite records. Now they put a lot of stereo reverb making full voice removal harder to achieve unless you use AI techniques.
I wish my college professors were this good at explaining electrical theory when I was in engineering school. Your videos would have been a game changer for me back in the day! Nice job.
Agree, about college professors, most can't teach. I'm an engineer with a mechanical engineering degree. I fully understood everything he explained. Not so much with professors.
If I may add my 2 cents to this tutorial:
1) In a Branch circuit, where you have a Black, White, and Green, technically the White is not called a Neutral. The correct term is the Grounded Conductor, and there is current on it, because the current has only one path to get back to the Source.
2) In a Single Phase system, as you would find in a Residence, where you have (L1), (L2) and (N), the Neutral is there to carry any unbalanced load between (L1) and (L2). In a perfect world where the distribution panel was perfectly balanced, there would be no need for the neutral. However, since you have both 120V and 240V appliances in the home, then the Neutral is needed.
To simplify the " PUSH-PULL" that Dustin talked about, it is important to remember that in a Single Phase system, (L1) and (L2) are 180 degrees out of phase with each other, meaning that when (L1) is at +180 degrees, (L2) is at -180 degrees, so when their currents meet up on the neutral, they basically cancel each other out, if their numbers are the same (+2A) and (-2A). (See Kirchhoff's Current Law)
Σ IIN = Σ IOUT. Kirchhof's First Law, conservation of charge.
There. Now we have a gen-U-whine formula (if simple) and I'm sure there will be some EEs tying themselves into little knots pretending it doesn't apply.
@@ethelryan257 Kirchoff is your friend! 🙂
Better bone up on AC circuits vs DC circuits because in an AC circuit you are dealing with Impedance, not resistance.
As soon as your load has anything other than pure resistance (incandescent lamps) there's phase shift between voltage and current and Power Factor comes into play. Think multiple devices that present reactive loads from motors, fans, ballasts and power supplies.
Sure, laws of charge conservation still apply, but are your ready to do the math?
With a low Impedance EARTH connection bonded to the Neutral buss in the panel how does that affect what he says? Does what he say about overloading the neutral connection (center tap) from the utility being of concern make sense? It didn't make any sense to me. What about branch or sub-panels?
Remember, this is AC power in a 3 wire 2 branch single phase L1-N-L2 120/240V configuration.
@@hbmike47 1) " Better bone up on AC circuits vs DC circuits because in an AC circuit you are dealing with Impedance, not resistance. " . . . . . . . . . . . There is Resistance in AC circuits as well. Impedance = Resistance + Inductive Reactance + Capacitive Reactance
2) " As soon as your load has anything other than pure resistance (incandescent lamps) there's phase shift between voltage and current and Power Factor comes into play. Think multiple devices that present reactive loads from motors, fans, ballasts and power supplies. " . . . . . . . . . . . A circuit with mostly Inductive Loads will cause the Current to Lag the Voltage by 90 degrees. A circuit with mostly Capacitive Loads will cause Current to Lead the Voltage by 90 degrees. A situation like this will cause the Power Factor to be less than 100%. However, these conditions are found mostly in Commercial and Industrial Power Systems, not in Residential. That being said, Phase Shift and Power Factor does not change the PUSH PULL narrative that Dustin spoke about, and the fact that current does flow on the Neutral in certain conditions. The point remains that Single Phase systems are separated by 180 degrees, and 3 Phase Systems are separated by 120 degrees.
3) " With a low Impedance EARTH connection bonded to the Neutral buss in the panel how does that affect what he says? " . . . . . . . . . . Connecting the Neutral Bus to EARTH puts it at the same Potential as the Ground/Earth, which is zero. There is no voltage on the Neutral, but there is current. If you put a Voltmeter across Neutral and Ground wires in a circuit, the meter will read zero.
@@hbmike47 " Does what he say about overloading the neutral connection (center tap) from the utility being of concern make sense? It didn't make any sense to me. ". . . . . . . . . If you are referring to the portion of the video at about 13:41, he is describing a situation where you have 2 circuits from the same Phase, (L1), essentially sharing a neutral. Because the circuit "Hots" are from the same phase (L1), there is no cancelling of any unbalanced currents, instead they add. So if one circuit had 3A on it, and the other had 5A on it, you would have a total of 8A on the Neutral going back to the source.
to be honest I like that you're drawing as you go, it helps to understand how everything is connected
It would have been a little easier perhaps if the phase plots of the voltage sources were shown too. This would also help explain in 3 phase Y, that the neutral carries the delta current, and how by phase, each leg will return a portion of the others current.
I don't know electrician lingo but it would not be the delta it wit would be the sum. Hot + center tap = 0
Thank You for another great video. It is difficult explaining a lot of electrical theory. It's really a pain in the butt explaining it to an electrician who kind of has their own theory. This one in particular seems to have been taught to a lot of Sparkys that I have worked around in a rather rigid way. So many of them will swear that two loads that are, say 5 amps each, will perfectly balance out and no neutral current will flow. Every one of them that I challenged to remove the two connections to the neutral bus and tie together then use any two fingers to complete the circuit back to the neutral bus, hot, just plain refused. Finding out how much they knew about WHY was revealed when I just asked them to explain the whole thing to me. Most of the time I was just told to take a hike, journeymen, dunno why most of them are so . . . stiff. Every time that I 'had my bluff called', I explained it with Ohms Law and showed the phase differences. I also would ask them why the neutral was there if it wasn't used.. I ALWAYS said that there is theory and there is practical use. They are rarely EXACTLY the same. Kinda like explaining how to drive to someone on paper, the finesse that is required in practical use is a bitch to explain on paper. Background: Retired after 30yrs as electronics tech in a facilities management department. I worked with two master electricians, one was educated in Germany and came to the US, the other has master tickets in five states. These two were very interested in learning more about electronics and I wanted to know more about power & distribution. We were a pretty cocky crowd and we loved a good problem. Open minds, required in service work.
It would be nice to see real wiring, real light bulbs and real meters showing the amps and voltages. Nice informative channel.
Light bulbs ? All a light is -is resistance between to connections. It not matter voltage , lights still work on all volts. You can not test voltage by lights. Must be by a volt metter for volts or a amp probe for amps and a hertz counter for hertz. Hertz is very important , it the speed of the volts and watts on material by the second. Usa is 60 hertz per second as south east asia and asia and middle east is 50 hertz per second. It ok to run a transformer for 50 hertz per second in a 50 hertz per second area . But not run a 60 hertz tranformer in a 50 hertz area. The 50 hertz core is thicker than a 60 hertz core so the curent can move slower on the thicker core , but can not move to slow on the core that the core made for the size of hertz travels over it. The slower the travel equals the thicker the core must be so it not melt.
I get what you mean. As you would see it on the field. Maybe photos would help a bit. IMO, anyway.
Ive been a lineman for over 10 years and I have to say I like where your going with this presentation. Its hard to grasp all the intricacies involved with electrical theory and after all it is just a theory. The best way I have found to explain the neutral in regards to a 120/240 service is it neutralizes the unbalance between both hot legs. If the panel in the building always had equal load on both legs the neutral would not be needed. When I troubleshoot an open neutral to determine if its on our side or in the home. The easiest way is to clamp an amp meter around the whole service. If the neutral is good it will read under 1 amp regardless of the load. Because current going opposite ways cancel out in the meter.
After all it is just a theory? You might have the wrong definition of theory in your head.
This isn’t correct at all
@Ryker u can only clamp one wire at a time, measuring amps not volts.
Of course you need a neutral wire, it connects to the light bulb
benjamin thomas especially at 8.40
Best explanation of this principle I've seen. I got that they canceled eachother out, but never understood where the current went.
As a long time educator, my compliments on a well illustrated and commented presentation.
The "on the fly" illustrations were logically and graphically informative, and well explained.
You get A for this assignment.
You should do a video on 240v circuits that don’t use a neutral. For instance a well pump. How it doesn’t need a neutral because it’s 240v only. That’s something that took me a minute to wrap my head around as I was learning.
And then there's devices that use 2 phases, a neutral, and a ground, like electric dryers! The heating element is powered by the 240v, but because the socket provides neutral, things like light bulbs that illuminate inside when the door is open can be normal 120v bulbs because it just grabs power from one phase and neutral.
@@Lierofox In the US, that's not two phases.
@@ethelryan257 Yep, misspoke, 2 lines, not two phases.
@@Lierofox it’s kind of silly that a lot of dryers also require a neutral. If some of the controls and control illumination/screens require 120v, they could engineer the dryer with a control power transformer inside to get 120v control power off the supplied 240v circuit.
@@RB-xv4si Doing so would add complexity and cost to the dryer.
I remember working for a college radio station about 50 years ago. We always made very sure that the loads were balanced on both sides of the neutral, both to make sure that the neutral was not overloaded and to keep any transient noise in the audio equipment (vacuum tube days) down.
Oh my! Taking me back to the beginning. Critical circuits would have trimming resistors. Amp tubes in the final would have inductive trimmers. Fortunately some tech from years gone by would have made notes in station maintenance logs so those could be preset with no power/low power.
@@thedillpickle100 that is very interesting.
@@thedillpickle100 - And you always installed a bleeding resistor on the pot capacitors. Once they overtightened the resistor leads and ended up with an open, which they then didn't test. So, when checking to be sure that the capacitor was fully discharged, we ended up with an arc-welded screwdriver (after a rather spectacular flash!).
That is the best answer I have ever heard. Best teacher ever.
I heard he is married ...
For me the easiest way to always remember that "yes, current does flow through the neutral" is that any two-pronged plug won't ever work when plugged into an outlet that's missing its neutral wire connection.
Half the outlets in our apartment are wired so horribly (swapped hot/neutral, missing neutral, no connection at all, etc) that it was a guessing game when I moved in. I wish I'd picked a different unit but this one's lease had already begun so I had no choice...
wait what? you think that current will flow through a single wire depending on what the outlet looks like?
That was an amazing explanation, I would only add one small part. At the transformer, the neutral creates the 120v by having the return path directly in the middle of the 240v transformer wires. And, explain that between the red and the white, you get 120 differential volts, but between red and black you get 240 differential volts. At any rate, that was an amazing explanation and I'll do a better job now of planning circuits in the panel of most used circuits so that the most used circuits are better balanced in the panel.
Really an excellent explanation! Important to understand for multi-wire branch circuits as an explanation of why the hots need to be on different phases.
Legs not phases. Unless you speak of 3 phase multi- phase branch circuits.
This would be a helluva lot simpler if you just show the two wave forms on a graph. The user could see that the troughs intersect at zero, and the peaks are the same magnitude and different polarity. This graphically shows the math, which equals zero along the whole line.
I was kinda thinking the same thing. I'm only halfway through the vid, so maybe he addresses it better but it seems like showing the pushing/pulling that the two balanced loads are doing, resulting in no net change in electrons in the neutral bar, would better explain why there's no current on the neutral.
Ya know, that's the way I usually draw it out to explain it, but that doesn't click for everyone, I am going to try explaining it more like this
If the neutral is balanced (cancelling out), does the current flow across the other hot wire? That's what I thought he was showing but I'm not sure about the bulbs becoming a part of a 240v circuit etc ...
If you want a graph google it 👍🏾
The neutral wire is often confused with ground wire, but in reality, they serve two distinct purposes. Neutral wires carry currents back to power source to better control and regulate voltage. Its overall purpose is to serve as a path to return energy.
To make the path easier to flow through basically right?
Actually positive wires carry current back to the source. Neutral is for AC. Therefore the current goes back and forth. Often, neutral is connected to say the frame which is then grounded.
Neutrals do not regulate voltage or offer control
@@rx7addict I think if the neutral is grounded it kind of helps to stabilize the voltages.
@@xxuncexx yes but that’s not the neutral itself. That’s an element added to the neutral to provide a ground reference
Thank you for this explanation it's been a question that I've wrestled with for the same reasons you said it aggravated you as a helper. This style of information presentation is excellent for those who did not have formal education in AC theory, or has taken AC theory but decades ago and cannot remember.
I'm glad I got to see you draw it. This is all new to me & it fostered a great step by step approach to understanding a complete circuit.
I LOOOOVE this explanation. It neatly lays out the concept of how current travels on single split-phase systems and cleanly explains WHY the neutral feeder will usually show very little current flowing while neutral current shows in the neutral wire going from the load to the neutral bar. It also explains why shared neutrals in both single-split-phase system need to be carefully thought out so as not to overload the neutral wire to the point of burning it up. I don't believe shared neutrals in a residential setting are common to begin with.
A continuation on this subject in a follow up video that explores three-phase commercial systems would be fantastic as shared neutrals seem to be incredibly common in commercial settings.
Question, (I'm fairly new to electrical) the diagram at 16:43, is this possible to wire? The hot from one phase connected to the hot of another phase with say a light bulb in-between. Will this work or be a fireworks show?
@@brandondill4234
What he had set up there was two 120 volt bulbs wired in series. Yes, they would work fine that way.
@@brandondill4234 Theoretically, you could. But why would you want to do that? Lamps are designed to run at 120 V and if you were to wire two 120 V lamps in series, you get 60 V across each lamp. That means both of the bulbs will shine dimly or if they’re LED, they may not shine at all. If one bulb were to burn out, the other would also stop working. To get both lamps to shine as bright as their designed to shine, you’d have to essentially run a new 240 V circuit. Therefore, it is unrealistic to have this sort of circuit in a residential setting.
@@mikejohnson3873 If you wired across the 2 hot phases you would be able to run a 240v rated device. I understand this is possible in the US if your installation is set up with the correct sockets etc. I have heard mention of this on other videos but had not fully understood how you could get 120v and 240v until I saw this video.
I am from the UK where we have 240v single phase domestic wiring in which the neutral carries all the return current back out to the street.
For 3 phase commercial systems each piece of equipment would take all 3 phases and would usually have balanced loads (with minimal neutral return current) so sharing neutrals would be less of a problem.
Nicely done. Would be of interest if you mentioned the consequences of an unbalanced load with a poor neutral connection and maybe some mention of the sine waves on the two phases that causes the push / pull effect on the neutral.
This was great, and I thought was going to address a confusion I have...almost did, but then didn't. I think someone else commented on this, regarding lots of time spent on the balanced load, but not enough on the imbalanced load. I get the 8A back through neutral, but I can't figure out how this is tied to ground at the same time. Arg, electricity is freaking magic as far as I can tell. Keep up the great work. I love this channel.
At the service entrance to your house (at the main panel) the ground and neutral are bonded together. This is the one and only place this bond occurs per the National Electric Code. This is done so that if a current carrying conductor (phase or neutral) touches ground, the stray current has a low impedance path back to the source which will allow a circuit breaker to quickly interrupt the fault. In a perfect world, current never flows on a ground. Think of the ground grid as a safety/backup path which stray current can escape on back to the source (instead of through a person for example). Neutral conductors are designed to carry current, unlike a ground. Think of a neutral as the normal/intended return path for current to flow back to the source.
Correct. The neutral and ground are tied together. I used to intermingle the wires until an inspector made me separate them. However, both are connected to the same place, which I pointed out. Never had a problem either way.
I love that you so people things in multiple different ways, to make sure they get it.
Nice presentation. I'm not an electrician, but have studied electrical theory out of interest, and the key fact that I took away from basic electrical circuitry a few years ago, was simple "the neutral carries the unbalanced portion of the load, back to the grid". During this presentation, I was waiting,...waiting,...waiting for your example,...and sure enough,...10a - 2a = 8a going back out to the grid !! Thanks you for such a thorough demo !!
Did you just break down Ohms law, power calculations and the physics of electricity in under 25 mins AND manage to squeeze in a rudimentary Thévenin’s equivalent problem for good measure?!? I believe you just did. Very well done sir. (*starts slow clap*)
On a serious note, you should consider teaching circuits at your local college of engineering. You would be a breath of fresh air for all the aspiring EE’s, AE’s and ME’s.
100% agree with this comment, you're better than most of the elect engr profs i had 30 years ago...
@@joem6859 My two profs I had for my electrical classes/electives for my aerospace engineering degree were fantastic. But... they did seem to forget that we didn't remember 100% of everything previously taught to us about electricity. lol
@@j36606 Exactly how is he completely wrong? His explanations fall in line with everything I’ve been taught and experienced.
@@neogator26 I somewhat agree with the other poster that some of his explanation is incorrect. I'd say he's definitely wrong regarding the neutral "canceling current and waves" because of opposition. That is not happening. The neutral carries half-cycles only. First, in a "positive" direction and then in a "negative." So, unbalanced current on the neutral is either flowing into the transformer or away but not flowing both directions at the same time for cancellation.
@@j36606 I'm not sure which specific explanation you're referring to, but I definitely disagree regarding "current and waves canceling in the neutral." That is definitely not happening in a single phase system..
The video seemed cut short a bit. Would have loved for you to spend a little more time on the flow in the neutral when you have unbalanced 120V loads between L1 and L2 and also touch on what would happen to the voltage of L1 and L2 if the neutral to the transformer was lost when the 120V loads were imbalanced. I know the answers, but would drive the point home while reiterating the importance of torquing conductors properly.
There was a house fire across the street from my house one time. The fire department cut power to the burning house and inadvertently opened the neutral to my house. The effect was expensive as I looked back and my house was very bright because of the unbalanced load now running through the lights. I lost a sump pump, a transformer controlling the thermostat for the furnace and a tv that night.
This video is excellent and right on the mark. Any comments regarding getting shocked while working on a neutral are just moronic, what are you doing touching a circuit with the power on? You have no way of knowing if the 240 circuit is running balanced. You cannot touch a neutral with power on.
@@finky555 Well, you can. Once?
Thank you for all these great presentations - as a mechanical engineer (from FoMoCo) decades ago, I am learning a lot from your productions (or forgetting a lot from my age). I agree with fellow viewers that it is better when you draw your presentation as you give explanations as it allows the "students" to follow your mind process instead of being "flooded" with a complex diagram to start with. BTW, what kind of interactive whiteboard screen are you using? Thank you again, Ciao, L
I was recently asked the question about current flowing in the neutral. I said yes. Now I know why people ask that question. The explanation is great.
This guy is a great teacher and he explains it very clearly. Ive learned alot from him !
I think the next video should cover grounding a neutral bar to add resistance
Lol what?
I thought the electrons didn't so much flow through the medium as vibrated back and forth and it was the electro-magnetic field that delivered the current to the load.
Yes, you are correct. The charged particles vibrate and the wave passes down the conductor..
I think when electricity is taught it is treated like the flow of water as a basic understanding. A physicist has a deeper understanding of magnetic fields etc.
@@fornife5004 Yes, precisely. Molecules of water leaving the pump outlet, traveling through the closed loop, and then returning to the pump inlet. It's a good analogy for a mental picture and for basic understanding. But, it's only an analogy..
This video and explanation is incredible!!!! Thank you, thank you Dustin!!!! These videos are a treasure to everyone who's trying to create a place for themselves in this world!!! This is true solidarity brother!!! I've always asked my teachers to explain some version of this...I probably wasn't asking the question the right way, so I never really got an explanation that was satisfying. I've done AC Theory and we've calculated balanced and unbalanced loads - I can do the math without too much trouble, but the "why" of it all never clicked until now! The electron and field/wave canceling each other out makes total sense, and the idea that the current will travel back on the neutral to get to the opposite pole completely makes sense now. Thank you!! Please, please explain why there is no current on the grounding conductor when there is current flowing on the neutral when the load is unbalanced?
Except it's partially wrong. The "electrons and waves" are not "canceling each other out." During unbalanced loads, the neutral carries only half-cycles, first in one direction and then the other. Current is not flowing in opposing directions on the neutral wire. In the balanced circuit, the neutral wire is completely irrelevant. The two lamps are simply in series with 240v across them..
Thank you.
I have spoken with a few electricians who did not understand this.
"How come a meter shows zero potential to earth if there's current in the neutral" is what they say and can't get past.
One thing, electrons hardly move in alternating current. They travel an extremely short distance one direction, then return to the starting point when the cycle switches.
A voltmeter doesn’t measure current.
@@GH-oi2jf
I find it interesting that you jumped on my misuse of a term, and ignored the claim I made that so many professional electricians don't just use an incorrect term, they have a completely incorrect understanding of how alternating current systems work. I said voltmeter to refer to a multimeter. You are aware that multimeters have an Ohm meter, a voltage meter, AND an amp meter?
I am not an electrician, never have been. I worked in a hardware store for years and dealt with electricians who came into the store. I made it a point to ask all electricians the same question. I asked because I had heard people say contradictory things and I wanted to understand what they meant. 'What does the neutral wire carry?', I'd ask. Only one guy said anything other than, "It takes the current back."
I'm no electrician, as I said, but if a wire only carries current in one direction, we are talking about DC, not AC. To be fair, I never differentiated between the neutral wire in an individual 120 volt circuit inside a building, and the neutral coming from the transformer to the meter/panel. Also, to be fair, none of the electricians I spoke with did either. If they thought my question only concerned the middle wire from the transformer, they would have said it carries the current for both the red and black circuits, which alternate directions at opposite times from each other. They would have then pointed out that equal, opposing, currents cancel. I never heard any of them say that.
Absolutely brilliant teacher. Wish I had a physics teacher like you in High School 55 years ago
It’s red leg and black leg. There’s only one phase. Great video! I just get bugged when people refer to A phase and B phase. It’s single phase.
It’s split phase with centre tapped neutral .
But the 2 legs are out of phase by 180 degrees, so how can it be considered single phase?
@@ashleypowell1623Because we measure phase to neutral. The waveform would look the same if we measure A to N and N to B.
Amen.
My respect for Nikola Tesla just increased further.
Who are u not to not have the highest respect for Tesla ? So high it can’t go anywhere more . He’s probably in the top 5 smartest man to ever walk this earth, ur over here learning his work and u don’t have the highest respect for him who are u ? Don’t worry about who I am cause I’m the guy fucking ur mom
More importantly than pre-drawing it, you need to have set a background color that isn't the same color as the neutral! I get it, you want to use the standard wire colors, cool. But the very very white wire on the very white background doesn't work.
Could have used grey for the "grounded conductor"
@@Darenator1 what is Dustin doing in the video
Best. Channel. Ever. WOW This is perfect. 180 out of phase cancels out, balanced. Awesome.
OMG!! I have wondered for years why the neutral bar in a panel wasn’t hot!!!!!
I always understood why the neutral may be hot at a switch/outlet.
THANK YOU!!!
I always understood why the neutral may be hot at a switch/outlet... oh yes?
There obviously ought to be a neutral present in a socket outlet or an appliance isolator, or a spur outlet... but in a light switch (at least in the UK) there ought not to be a neutral... The neutral wire, at one time black, now blue, is used as a switched live, flagged / identified with a piece of red insulating tape... Most of the time...
After years of not "getting" it. Brother you made it make sense. Kudos!
So in a nutshell, the neutral carries the difference between the two phases when they're not in perfect balance.
Bro, that diagram you made showing that while the push and pull is happening on each phase, the neutral is experiencing the same thing, but in one conductor, therefore cancelling the current...
Sometimes it just takes one person explaining it in the right way for the brain to understand and loads of other stuff falls into place.
Thank you for that
Awesome Job! As a systems engineer for 30+ years No EE has ever been explain it this well. I especially like the implication of an unbalanced load and why my HVAC has to be 240VAC
3:22 point of clarity that most people don't understand about the flow of electricity. The electrons move, you are correct, but the electrons only oscillate in a finite distance and don't actually flow or move any appreciable distance. It's the wave form around the wire that actually flows and creates what we know as electricity. I'm oversimplifying it and don't really understand it 100% but thought I would point that out.
As a DIY hooking up a 240V well pump and a 240V baseboard heater system this video solves all my potential questions. Thanks...
I just found your channel. You're a bad-ass teacher. This video taught so many things that a conventional educational video wouldn't even know needed to be explained.
One of the most impressive things to me about this video is that it takes 23 minutes to give the simple answer that is given in exactly one second between the (spoiler) 4:23 and 4:24 mark.
This is great. Easy to understand and interesting at the same time. I love how the freq. cancelling holds true for the entire EMS.
Just found your channel and I'm very excited about it. Thank you so much for taking the time to explain these things!!!
Nice. Nice to see you added the fields and discussed about them. They are a growing significance in PCB Design and Higher Speed conductors as well.
Thanks !
Just come across this channel and found the explanation very clear. As an electrician based in the UK you wouldn't think this would be too relavnt but we have three phase installatons running at 400 to 440 volts and Balancing the Phases is an important safety factor ias all the phases combine in a single neutral cable and badly balanced phases could cause an installation failure or a FIRE! Your maths uses diffrent symbols. In the UK Ohms law is U=IR, the U standing for Voltage Source while V is Voltage potential. Never mind, I gave up at short tons, long tons and Metric tonnes. Just so long as we all understand each other !!!! 🙂
A few fun facts somewhat related to this:
1) In most sparsely populated rural property power is delivered in high voltage buried cable from the power pole to the step down transformer by the electric meter. In my case is 7.5kV single phase via a unground coax cable. From what I infer and research it is called single conductor despite it has the aluminium center core and a outer conductive shield, the shield does not carry the return current. Instead, the earth does despite of its high resistance which is feasible because of the high transmission voltage. This scheme is called single-wire earth return.
2) The step down transformer converts this single high voltage hot leg of 7.5kV down to two hot legs of 120Vac with one shared neutral. The return current of the primary winding travels via earth back to the substation.
3) Power generation stations and the power transmission out of them do not use a neutral because they is done by 3 phase. 3 phase delta has 3 hot legs and no neural.
4) While most residences use only 1 phase AC, they are derived from any one leg of the three phases. Because of this, a 3 phase wye power conversion must be involved.
The return current on the
V Sohn. You are wrong on many aspects of your comment. Old underground cables used to have the neutral exposed, which, over time decayed. Newer cable has the neutral jacketed. Nowadays, most distribution circuits are a Y system, meaning they have a neutral. The neutral is a solid connection hooked to the Xo bushing on the low side of the transformer. All 3 phases and the neutral are hooked together internally in the transformer. On a delta system, there is no return or neutral wire. These systems are dangerous, due to the fact you can literally ground one phase in the system and it will not trigger any protection or relaying on that circuit. Delta systems are not preferred due to the safety factors compared to a grounded Y system.
@@kenchiison4570 The thing is smart people always be aware what they don't know, and the opposite think they know it all. You are seeing things from under the rocks that is the universe you perceive. Read my comments more careful as why I think delta three phase is use for long distance transmission. Delta transmission for thousands of mile requires 3 conductors, while wye requires 4. It does not take Einstein to figure out which one to choose. Neutral and ground is not a high power very long distance (as often interstates) electricity transmission requirement.
Neutral and ground is a local last mile, if not last hundred yards thing. Tell us what is your professional credential. I am not a linesman, but I am a EE despite high power and electrical distribution is far from my expertises.
@@maestrovso .If you're worried about cost, you would just convert to DC and only have 2 wires. Look at your transmission structures. Up on the very top. Usually 2 static wires up there. Used for lightning protection and sometimes have a fiber optic cable in them. Usually tied in to the substation and a pole ground at each structure. Even if it's a delta. You can have a 480Y or a 480 delta. The equipment will function the same. Which one would you prefer?
@@kenchiison4570 You are so out of your depth that it shows. Please when you see those high tension transmission line steel towers next time count the number of cables on them. If there are three they are delta. delta and wye both are user for electric grid, and they both have their uses. I am talking about power grid distributions that is tens of thousands of volts.
Like I pointed out, you view of the system is imprisoned in your little sphere of your myopic view.
@@maestrovso No 5hit Sherlock. 3 conductors but there is still a static wire above, usually. The point is, whether it's delta or wye, it usually has a static wire above for protection, and or, communication.
That was so enjoyable to watch cause you are so honest and natural about your explanations!
It's great you like it, But Don't take his stuff too seriously.
His explainations are filled with errors.
I think the biggest thing that confuses people is taking that all “electricity” is current.. hence the confusion of current source versus voltage source stuff like that.. once people get just the basic idea of what voltage actually is compared to what current actually is, i.e. talking about fields, versus the flow of electrons, makes everything so much easier to understand!
Getting beyond that comparison to water the most people are taught to compare it with, and have that stick in their head. Makes actually learning and understanding stuff a lot more difficult.
You have such a good balance of bringing in people that I’ve only worked in the field, as well as people that might be engineers, it’s a really good balance and I appreciate that very much!!
We definitely need more of this in electrical, HVAC, etc. etc.
Current is the real physical parameter of electricity. Technically, there is no voltage. The final form of Maxwell's equations has no voltage in it. Now this doesn't mean that the concept of voltage isn't useful--it's incredibly useful. But current is the key.
BEST explaination of a Main panel...like, ever. Mini loops!
Well delivered info. The drawing done as you explained it is the only way to do it in my opinion. Electricity is one of those things that is difficult to grasp cause you can’t see it but you helped clarify. Thankyou thankyou. Keep it up, well done.
Liked and subscribed!!
YES! If you saw how the neutral and hots are attached at the transformer outside, you would understand.
Bro you actually explain stuff so we’ll, and with your board drawing and explaining at the same time, It is VERY helpful for me Personally to understand
Thanks just subscribed
Great explanation to the topic. Makes me absolutely stop adding circuits to my house until I see how it applies to determining where and how to add a circuit.
Even I need to watch this few more times maybe a thousand thousand spectacular learning session. Recently I've been questioning the common side of just a small 24 volt circuit which led me to this great demo of how current close in a home
I reallly love the way you explained everything in this video.. i remember when i was learning i could never understand this because my teachers had a difficult time explaining it in a way everyone understood. I am so bad at explaining how Electricity works to someone that is new and teying to learn cause i makes sense in my head just cant put it in words. You have a true talent at explaining Electricity
a beautiful explanation. it solved my problem to use a single 12/3 wire for kitchen microwave and kitchen coffee maker on two different outlets without causing overload on neutral. cool. thank u.
11:24 that blew my mind, awesome!
This video was excellent. It's remarkable how many people have worked in the trade and never understood this concept. Years ago I worked in the Electrical-Mechanical shop of a large university. Only a couple guys in the whole place new this concept. I learned this when I was trying to install an electric water heater. NOW, think about 3 phases and 480 VAC. That jazz really messes with peoples minds. Add to this I have seen guys who could explain some of this but could not install a water heater, properly. Another thing that baffles the masses is that a VOM does NOT measure electricity flow; it measures the voltage differences on conductors. It's a wonder why our grid even works at all. Sometimes I think I live in a third world country. Keep up your good work.
Hats off on the informative video…recommend taming the high energy back ground music! Distracting!
Now I understand why there is a neutral on a 220v circuit, potential path for unbalanced loads (unequal current usage). For current to flow back to the transformer, the legs have to give and receive the potential equally, the neutral is for the unequal potential. Got it, ty
Very awesome video.very educational for someone that knows a little about electricity but you really laid it out perfectly with your drawings.what a great lesson.keep the knowledge coming.👍
I am old and English is my second language but understand the way you explained, that makes you a great teacher
This gentleman is a good teacher. Another good explanation of the North American split-phase power delivery is a video by Engineering Mindset.
As far as does current flow on the neutral, it has to; otherwise there wouldn't be a circuit.
That is eye-opening. Thank you for this. Now I have to let it soak in and mull it over. Lots of new info and different ways to think about things I thought I already knew…. You are a great teacher.
This old 1952 John Deere B, has positive ground, and negative is hot!
Ended up been lost in the colour at the end but loved it, I ended up understanding lightening. Brilliant.
Dude this was the best explanation for me! Finally! Thank you so much!!!
👍💯👌 Best explanation i ever got!!! about N wire. Excellent electrician who perfectly know his job! Good luck. Спасибо большое!
This information would’ve been awesome 25 years ago when I re-wired my entire home from attic to basement… To know that people are still running air conditioners off of Knob and Tube is amazing 😳.. There was even 12/2 wire connected to it under floor boards… What a mess….
I love the way you break things down
Yes, a neutral wire can carry an electrical current when it's being used as a return source for power.
So that's what balancing circuits is for. I've wired 5 of my own homes and never really thought this way. My next remodel I'm going to use this information, thanks so much.
Thank you ! This was amazing. I'm being trained to become an apprentice and this was very enlightening. I'll share my notes with my classmates and direct those who speak english to this video.