A drawing and diagram of the path electrical current takes in typical single phase north American residential service #nationalelectricalcode #electrician #electrical #diy #electricity #200amp #romex #howto #3wayswitch #christmas
Great videos by the way. I'm a 20 year journeyman and still learning new things everyday. Hard to find expirience such as yours willing to share their knowledge.
As an electrical engineer I approve! 👍 Lots of folks don't understand AC voltage and current, thinking it's like DC. Then you've got the complexities of R.M.S., inductive and capacitive loads, magnetism, transformers, capacitors, 3 phase power, and all the messy calculus math in it. Thanks for making things simple for the lay person, even jouneymen, and apprentices. 😊
Lmfaooo don't ever talk about journeymen as an electrical engineer because you people are the ones creating 💩 that doesn't work and electricians are the ones making your mistakes somehow work lmfaooooo
Thanks for this. I am a meter man for a local POCO. Been trying to explain this to Linemen. I will send them here for your very clear explanation. They always incorrectly refer to the Neutral as Ground.
Thank you for taking the time to share your knowledge in a trade that is critical. This will help more people than you think it will or that will say thank you.
Thank you very much sir, that was very informative and by showing the diagram with the 2 different colors and the arrows you made it very easy to understand. Thank you and keep up the hard work!
As an HVAC technician, my three phase knowledge went as far as knowing that my wires were in the correct position so that my rotation was correct. It was cool seeing the why and how of three-phase electrical. This was a great and well explained video, and thanks for taking the time to put make it.
This isn't 3 phase, it's a single phase centre tapped transformer arrangement. Both legs are out of phase by 180 degrees, whereas 3 phase has 3 legs out of phase by 120 degrees.
People really struggle with split phase AC, it actually helps to look at 3 phase for some, but opposite for others. They can’t understand that the neutral is a hot wire for half the cycle, since it can’t which them while being grounded like the hots can. Difference of potential hard to explain, but you have the teachers gift.
The only suggestion I would make is the choice of words. Instead of the neutral providing the extra amps I might phrase it as the extra amps are taken from the nuetral by the more negative leg. My intuitive model is one where AC pushes and pulls, and I think the hangup people have is in the notion that neutral is an active agent in some sense, so "taken from" gets around this. Dunno, maybe just me.
Personally I think it is easier to understand if you look at it as two 120 Volt supplies in series. You have a voltage of 120 sin (kt) in series with a voltage of -120 sin (kt). Since one of the currents is negative, the neutral carries only the difference. Technically they ARE adding in the neutral, but since one of them is negative (opposite polarity) the final result is the difference. I don't think it is so wrong to say that they cancel. Maybe that is just some people's way of understanding it. They call it "canceling."
Superposition makes more sense. The currents don't cancel, but instead a sum of all currents is whats measured. Kind of like how you can have a bunch of forces acting on an object but it's the net force that determines the movement of the object. Those individual forces still exists. I'm not entirely sure, but it sounds like you're thinking about "canceling". Because the topic focuses on current, not volts.
@@waroftheworlds2008"Cancel" is not the word I would have chosen. The situation is pretty simple if you use KCL. The neutral current is simply the sum of the two hot currents. But since the two hot voltages have opposite polarities, the magnitude of the neutral current is the arithmetic difference of the magnitudes of the two hots. But if I was trying to explain this to someone and they said "oh, the currents cancel out because they are going in opposite directions" I wouldn't say that is wrong.
Very good, was clear to me a layman, a mr. fix it. ? I would like to cover the 2 main lines coming in to my fuse box, so I can safely work in it, is that possible? Thanks,
So positive current comes from the transformer, into the circuit panel box, out through a circuit breaker,to, an appliance, back on the neutral to the neutral, ground block in the circuit, breaker panel, then goes out on another neutral to an appliance on the negative cycle of the sine wave, through another appliance, and out through the hot back to the transformer? It seems like a lot of neutrals will have current on other appliances on the opposite sine leg. What I can’t grasp, is, why would you need amps going through an appliance on the negative cycle? Maybe because it’s on the negative cycle. It needs to get back to the transformer. So at one point all of the neutrals in that circuit panel box may actually have current going through them on the negative cycle, or positive cycle depending on the sine wave. you did a fantastic job on showing me how current actually travels. If anybody else can help me out here, it will be appreciated.
you don't need to know current direction during the cycle in a day to day life. just have to remember that the left side is 180 deg of the other side and your good so you have 120V on one side 120V on the other side the sum equal 240....
yep the load, if you plug your cell phone charger on one side and the hair dryer on the other side the load are not balanced but there is no real issue to it , unless you decide to overload one side and don't use the other side
The problem might be terminology. When looking at a transformer, the "neutral" is a center tap not a called neutral. So the concept of "neutral" is that it should be inert and not source any voltage or current, and you clearly show that it is not the case... Well, It's been a long time since I took electronics so I'm watching you and thinking, there's Kirchhoff's circuit laws basically account for all the voltages, I guess also current, this was a little sloppy on terminology and I'm just as guilty to call things power current voltage almost interchangeably, but you get your point across and I understand what you're saying... Basically, that Current has to add up to zero all around... i.e., if the total is X then all the elements must add up to X, the center tap will be the difference in the different phases. So I'm sure that something in those electronics tech course could a good way to back up your points... but please check into my information before presenting because I don't want to guide you wrong... there's enough of that going on these days. LOL.... Cheers!
Interesting. That explains the voltage fluctuations when I had a problem with the neutral after an ice storm some years back. So what is the function of a ground rod, just out of curiosity?
How about an isolated transformer? We have isolated 480v to 120v transformers on our buckets at work. We had a Apprentice go around and ground them to the frame. Seemed to cause issues so we removed them. Do they need bonded? I said no. They are no longer isolated at that point. There is a potential for an electric bleed off to the frame in case of a short. What are your thoughts on them?
Normal stuff need to be grounded Some RARE equipement will use isolating transformer for safety but you don't see that often anymore Like the old razor plug in the bathroom ...was an isolating transformer so you could not GROUND yourself even if you wanted to Now a day they use a GFCI plug that trip when it detect that you are GROUNDED lol
I know where that amperage is coming from. the computer system lights and relays operate on a 120V circuit. In theory there's a way to do it but you would have to install a 220 to 110 transformer. The problem with that is it makes it much more complicated.
So. is that how my 240V 3 wire works? Was wondering how/why no neutral wire at the tub, but has 4 wires at the breaker box on the side of the house by the tub.
ok... but what if i have a HUGE inductive load on 1 leg.... and all resistive heaters on the other leg? . AC electricity is so strange to my automotive tech 12V mind (and some 6V stuff.... which can get REALLY strange.... EX 74 kawi g5 100cc... if headlight burns out, brake light gets all the power, and blows every time you hit the brakes lol) . i have yet to find a positive ground however.... yet i know they exist
If I am correct.....At the end, you say that there is 1/3 of an amp imbalance. That 1/3 of an amp imbalance is because the electronics, the timer, etc. is a 120 volt device, and is put across one side ("leg") instead of across both sides. that is using up that small amperage. That's why there is a small imbalance.
I’m an apprentice and this perplexes me. Why are 2 hots needed in the first place? Is it possible to run one hot, one neutral and still get the box to work?
You still have to have a reference point somewhere. If you used a single wire with earth return, you could have 1 hot and 1 at ground. That's essentially what's coming to your house, but now the ground is center tapped in the middle of the 240 to give you 2 opposite legs, with the center being grounded and tied to your neutral.
Actually i am curious What would happen if you touched a bare neutral Would it cloae the circuit just like touching live and make electricity flow through you?
Hi bro..... The matter is related to two currents running in the opposite direction so the result I(total)=i1-i2 the differential current passes across the neutral, based on the transformer concept
The way you do it in lots of your video is unconventional for me Over here we just do do like you did arrow from H1 to neutral point and neutral point to H2 and just substract value in the neutral branch because arrows are point in reverse direction inserting current direction during cycle in the same explanation will just lose most poeple and it's not of much use on a day to day basis
This all sounds good and rational, however just like the kids in high school want to know what is this math all about and how relevant is it. If the relevance of this is only in the electrical engineers sphere that most electricians will never dwell in, show the relevance to regular people on how this matters and is used to figure out an issue.
Its about having an understanding how how stuff work. It about wanting to be more than just an installer and actually being an electrician. If you understand this GFI and a the rules for bonding and grounding should become intuitive
