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The visual aids and clear narration makes this video tops. I am amazed how much I just learned in 13 minutes. Super educational. Thank you very much from this new subscriber.
A short circuit should always trip the breaker. Ground fault: no guarantee. I recently had a ground fault that took me hours to find - and it had been there, undetected, for 40+ years. A new UPS indicated the ground fault - and started the hunt. On my electric furnace (20 kW) one of the hots got loose. Furnace still worked - but the arcing melted the connection block - I had to replace that and some adjacent wires that got damaged. I now torque that each fall before the heating season.
Another great video. Electrical systems initially are pretty straightforward but there is a bit of nuance to them to really get a good understanding of them and understand why particular codes are there.
I installed an AF/GFCI breaker in my kids bedroom for those exact reasons. Maybe they accidentally poke an outlet or maybe they damage a cord using it as a rope.
Basically, in the American system, the breaker also protects against ground faults for indirect contacts, which are the statistically most dangerous faults...for direct contacts and neutral-to-ground faults we use the GFCI.
We in Argentina use both GFCI breakers and the regular brakers. You don't need a ground wire nor grounded rod to activate the GFCI breaker, because if you touch a live wire or a (metal) fixture that has a hot wire touching it in a fouled way, your body acts as the path to earth. This event doesn't kill you because the current gets interrupted before reaching 30 milliamperes (which are considered deadly). The real use of the Grounded rod and the ground wire is to prevent fires when an electric arc occurs between the hot wire and the neutral wire (they need just 300 milliamperes to happen, that can't be detected by the regular breaker. You just need to connect the GFCI breaker in series with the main braker, and the whole electrical installation is protected.
En realidad no es asi, el diferencial de 30mA que decis vos solo te protege ante el contacto indirecto, para que si tocas la chapa metalica energizada haya una tension de contacto maxima de 50V en el momento de la derivacion con una resistencia de suelo menor a 1660 ohms (50V/1660 ohm=30mA)... si tocas el vivo desnudo y descalzo (contacto directo) te aseguro que por ley de kirchoff recibiras mas de 30mA y lo unico que te "salva" de morir es ese pequeño "lag" o "tiempo" que tarda en activarse el diferencial que son entre 15 a 20 milisegundos. Es un error comun creer que el diferencial es un limitador de corriente mas bien es un limitador de tension de contacto.
God bless you people! You make great videos ( like most uk, us and german videos) must be something in the way saxonic languages are structured that makes your thinking so logical and clear.
Hey, love your videos! I have a request if you have a request/suggestion box? Not related to this particular video though, but here goes: It would be cool to know why we can use a 3 phase motor with a capacitor to power a 1 phase load 230V. How does the 400V between phases become 230V just because you put a capacitor between 2 of the phases?
I don't understand the purpose of the GFCI outlets. Isn't there already a 30mA differential breaker in the main electrical panel? I am French so I wonder if this is not the case in America.
A lot of European service panels have RCD's built into them, which as you said trips around 30mA and protects any circuit breaker connected to it, so the need for GFCI would be indeed redundant. On the other hand, North America does not have RCD's built in. The standard service panel in North America has a main breaker, the circuit breakers - which are only there to prevent the wires from receiving more current than they're rated for, and then the busbars for neutral and ground. So unless you go out of your way to install breakers that have arc protection and/or ground fault protection, there is no protection for the people, only for the property. Hope this helps!
Gfci monitors between current going out vs returning on neutral. Its possible for current to leak out of a circuit but also have enough impedence not to short out completely. You could become a "load" and a normal breaker wouldn't know the difference. Thats why they are required around sources of water like sinks or pools. If current leaks into the water and finds another path to ground the GFCI will see this difference in return current and trip.
@@Kanis5000 this doesnt really answer their original question, they were confused as to why gfci outlets are a thing because they thought all service panels had a rcd by default.
They act as a superquick breaker right there at the GFCI outlet...not only do you have to worry about the energy exposure to the current across the body, if current travels across the heart, the heart can be thrown into arrhythmia and cause a heart attack. The GFCI instantly trips to minimize that travel time to the normal circuit breaker (the normal breaker won't even heat up) and exposure to minimize the shock risk. That's what they are really intended for.
My question is: if the effective ground fault current path completes the circuit in a normal fault current situation how come that instant increase in current trips that branch circuit breaker first and not the main breaker or all the breakers for that matter? Since A/C is flowing back and forth and the low resistance of the EGC causes such high current wouldn’t the direction of current flow-at least for a brief moment-bring that high current through the main breaker and onto the bus bars it protects which would trip everything?
The branch breaker has a lower threshold, it should therefore trip first. If it doesn't, the main breaker should trip shortly after, depending on the size of the current passing through it.
Thanks for the excellent video. What is behind the increased resistance of the ground wire/rod route compared to the neutral wire route? Is this just due to increased resistance of dirt compared to a copper wire? Thanks
the GROUND path from building to pole is just dirt, you know dirt is very bad on conducting electricity, but resistance varies depending on soil conditions like rains or illegal discharge of pollutants that contains heavy metals
oh wasn't aware the GFCI isn't a very regular thing .. i don't really understand the difference between a GFCI and an ELCB (we call it FI falut current indicator often called main fuse by non electricians) or is it the same thing?
5:17 Hah, this is allowed or even required in a lot of European countries. Obviously in this case residual current device(gfci) on all circuits is mandatory. We have panel mounted ground fault only breakers here, the standard overcurrent breakers are downstream from it, as far as I can tell the US only has combined ground fault and overcurrent available? Would be very expensive to fit a whole panel with that though a lot of Western Europe is actually doing that.
@@jm036 i guess that's nice but why not add something like a central 50mA rcd (or whatever would the 120v alt be) for redundancy? is there some reason or just not implemented
I am subscribed to this channel and TH-cam is not showing this video in the feed, even after 3 days. This popped as a suggestion only because I was looking at some other grounding related videos.
Fault current is instantaneous, the circuitbreaker is lowest rated so should trip first, if for some reason it doesn't then the main breaker should and if that doesn't then the transformer fuse should pop
That is a good question to ask. The reason that the downstream breaker trips first is this: Every overcircuit protection device (whether a breaker or a thermal fuse) takes a certain amount of time to react. A typical breaker/fuse will trip nearly instantly when a massive overload happens (think >5x the rated current). A more modest overload, like 2-3x, may take several seconds to trip. So a 600A fault current on a 200A breaker would take seconds to trip, while the downstream 15A breaker will trip instantly because the 600A is _far_ in excess of its instantaneous trip threshold. (In the circuit breakers used in electrical panels, two distinct mechanisms can trip the breaker: a thermal mechanism acts slowly, and is for modest overloads. It trips once it gets hot, which is why it acts slowly. A very modest overload can take many minutes to trip! The second mechanism is magnetic. The current flows through an electromagnet, but at the rated current (and a few times above, e.g. 5x), the magnetic field it causes is too weak to trigger the breaker. But a large fault current causes a strong magnetic field, which instantly trips the breaker.)
Thank you @tookitogo and just to add that, we have shown this is a previous video (Based on Din rail breakers) th-cam.com/video/gqEu9t8HwW0/w-d-xo.htmlsi=crCY59fy_QpK6EJE&t=812
The main breaker limits what amperage to cut power at. The circuit, wires and breakers, themselves can experience thousands of amps or any other amount they just won't be able to handle it and melt.
Question for you electricians who are smarter than me. I have a friend who lives in an older home with old wiring. It has a fuse box and with no appliance ground wires in their home runs. Short of rewiring the home (which will be done in the next year or so), is there a difference or reason for using a GFCI receptacle vs. just a regular 3-prong receptacle? How would you recommend a temporary work around? Thanks in advance!
I've heard of arc fault detectors in English speaking countries, but have never heard about their existence in my region (Belgium, Netherlands, Germany, France). With regards to earthing, are these systems called the same in the USA? TT, TN, TNC-S, IT?
Yes, it's called AFDD (arc fault detection device). And you can get combined breakers with rcd and afdd from 6-40A(eaton), 10-32A(schneider). Ofc other producers have them aswell.
so normal circuit breakers only trip if there is short circuit but if the path is between the body it will still be lethal. while gfci could detect current difference between hot and neutral even when the body with high resistance is passing current, so it will trip on ground faults. circuit breakers saves electricity bill and also fire hazards while gfci saves electrical hazards
Electrical engineer here: Circuit breakers trip based on either 1. max current or 2. average current over time. 1. In order to measure max current, the breaker has a small electric magnet powered by the current flowing through the circuit. The magnetic force is porpotional to current, and at a set point, it is stronger than a spring, tripping the breaker. 2. Average current over time is measured using a bi-metalic coil. As the coil heats up, it starts to unwind, and at a set point, it is stronger than a spring, tripping the breaker. An important note is that the current creates a constant rise in temp that eventually reaches equilibrium with the surrounding area. This means that if you have multiple overloaded breakers close together, the rated average current will go down. Gfci breakers (ground fault circuit interupt) used the same principle from #1, but instead of a spring, it uses the return path of the circuit. If power is divert from the return path, such as whe a person gets shocked, the break trips. Hope this helps. Edit: phone lagged and posted mid writeup
This could be normal in GFCI receptacle or regular receptacle as well. Plugging in a tool or appliance with the power off (tool or appliance) will prevent this problem. If the receptacle is old and/or not gripping the cord very well, you should change it. Check the plug condition also.
It often is normal. With electronic gadgets (which use modern switch mode power supplies, like phones, computers, TVs, etc), plugging them in charges a capacitor in the power supply. This is an instant huge current. Most of these devices don’t have “real” power switches, so when plugging in, you’re always plugging it in “hot”. Similarly, larger appliances with motors or heaters can also spark if plugged in while turned on. In all cases, the size of the spark depends on when in the mains waveform the connection happens. If it’s right at the zero crossing, nothing happens, if it’s right at the peak of the sine wave, the spark can be much larger. Since that happens 100/120 times per second (both halves of the 50/60Hz line frequency), it’s random to the naked eye. You can always eliminate sparking by using a switched power strip in between, and only plugging in with the strip switched off.
@@tookitogo Good information, you're right about TV's, computers, etc., and they are normally plugged into surge protectors/power strips and left plugged in all the time, so sparking would not be an issue.
Very short momentary arcs are normal as only voltage is required to start at arc but when amperage is added and there is a suatained distance between two points is when it becomes dangerous. The amps will sustain and increase the power of the arc depending on how many amps. The amperage is determined by the load draw but as long as you don't have something big on when you plug it in there should be low risks.
I mean, if you have full ground fault protection on the whole electrical system (like the UK electrical standard), both are equally dangerous. And much safer compared to without it.
As an electrician in America, I can tell you it sounds like a nightmare if something trips the system. Your entire dwelling loses power until it's found. Unless there's something I don't understand about that system. And this video is either old or they're not keeping up with the codes. Now, everything has to arc-fault protected, and the usual wet locations need to be both arc and ground-fault protected. Individual breakers makes it much easier to pinpoint a problem vs. the entire home shutting off.
@@snakeinthegrass7443 we do have individual over current breakers which is downstream of a residual current breakers. For overcurrent, you will always know which ones are tripping. For Residual current (ground fault), yes, you would have to flip all of them. The good news is that, for wet places, because of the standard, usually a more sensitive residual current breaker is used. So you don't have to flip all the breakers, jus guess which group it is and start there
@@snakeinthegrass7443I have pretty much the same regulations in my country (France(?). And yup, sometimes the whole house trips due to a defective device. But as OP responded, you have enough breakers to isolate the cause ! Moreover, there's a differential per neutral bar (Abt 10 circuits per bar if I'm not mistaken). Sometimes, it's not the whole house which trips
ANYONE???!!! A coil with an inductance of 500 millihenries has the current through it dropped from 20 amps to 2 amps in 5 milliseconds. What will the induced voltage be? Will it be in the same direction or the opposite direction to that of the source?
Why not just install one GFCI or any current differential detector on the main panel instead of having many on individual outlets? One in the main panel could protect all the outlets. I understand there are GFCI breaker for the main panel, but then why bother with GFCI outlets
I just moved to a new state and I didn't see GFCI in the bathrooms, so I went to the main panel, and lo and behold, GFCI right there on the main panel. I had no idea they ever did it that way. Only downside is its further away if you've gotta reset it lol
because identifying a ground fault in that system would be stupidly annoying and complex, leaving you without power throughout the house just because a lamp has poor quality electronics that leak to ground. Also, statistically most electrocutions are due to indirect contact and the circuit breaker will trip perfectly well in that situation, modular GFCIs are more for specific situations like a bathroom or damp locations. That is the strength of the NEMA system over IEC
The algorithm is mad because you're obviously promoting dangerous things like touching live electrical wires. You should be advocating electrical safety, like Mehdi. (/s because someone won't get it.)
Electrical engineer here: electricity is safe as long as you don't pick it. It is also wise to not question it, for the demons that live in the wire are vengeful. But the wards often hold making the ardent energy flow.
Dear Sir/Madam, I hope this message finds you well. I am currently a university student pursuing a degree in Control and Automation Engineering. I would like to seek advice from experienced professional engineers, or those who have at least had practical experience in this field, regarding a book titled "Electric Circuits," 10th edition, by James W. Nilsson and Susan Riedel. The contents of the book’s chapters are as follows: 1. Circuit Variables 2. Circuit Elements 3. Simple Resistive Circuits 4. Techniques of Circuit Analysis 5. The Operational Amplifier 6. Inductance, Capacitance, and Mutual Inductance 7. Response of First-Order RL and RC Circuits 8. Natural and Step Responses of RLC Circuits 9. Sinusoidal Steady-State Analysis 10. Sinusoidal Steady-State Power Calculations 11. Balanced Three-Phase Circuits 12. Introduction to the Laplace Transform 13. The Laplace Transform in Circuit Analysis 14. Introduction to Frequency Selective Circuits 15. Active Filter Circuits 16. Fourier Series 17. The Fourier Transform 18. Two-Point Circuits My question is: Do I need to learn all the material from every chapter of this book in order to perform the tasks of a Control and Automation Engineer? Additionally, what steps should I take in my learning journey? I sincerely appreciate any guidance or suggestions you can provide.
If you want to be the best in your field, get promotions and solve problems that other people can't, then yes, learn it all. You don't necessarily need to remember every part, but remember where to find the answer. Make notes, take screenshots, keep a folder of information and solutions you can look back on in future. No one is born with knowledge, it is something we acquire over time with effort.
Meanwhile Gallium Nitride adapter companies: Let's just push more high watt charging capabilities towards our adapter but we still make the connector with Hot and Neutral only without ground. Who needs ground anyway 😅 That's why USB4 or USB-C Power Delivery are pretty much fire hazards if the adapter itself don't have Grounding pin.
For all commenting angels if want a video on how a calculator works then like. So that this comment can fly away to the video editor or youtuber.😢 The person will explain briefly.
As a Frenchie, I don't know why electrical installations look so unsafe in other countries ? 😅 EU and french (NF) rules are very complicated, but I know I'm safe in every single condition ! I'm glad they exist when I've uninstalled a radiator, and the current was still live (even though the breaker was off. Turns out, it was mislabeled. I could have died 😂
@Phil-D83 they don't save lives they rob people. Normal breakers work just fine and always had. And when you replace a panel in an old house, how come there ok with not installing them there where the wiring is a hundred years old? Answer that. Afci breakers are useless and are a scam by corporations and companies that make them. They should be a choice not a requirement
Breakers are a scam. Neutrals are a scam. Switch legs are a scam. Dedicated circuits are a scam. Grounded receptacles are a scam. Splice boxes are a scam. Junction boxes are a scam. NEC is a scam. /s
Can anyone help; I've got 2 sockets upstairs both do not have any power coming through the live, instead the neutral and the cpc are showing as constant live? Every other outlet is ok. I checked with a socket tester and the phase and earth is showing as a fault. No breakers are tripping or have tripped at all
*This free video took WEEKS to make!* If you’d like to support Paul’s efforts, links below:
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😊😊
Hello sir please🙏🙏🙏 explain DC wire vs AC wire thank you ❤❤❤
Sir can please make videos about ne 555 timer and square DC wave generator videos please 🥺
The visual aids and clear narration makes this video tops. I am amazed how much I just learned in 13 minutes. Super educational.
Thank you very much from this new subscriber.
A short circuit should always trip the breaker. Ground fault: no guarantee.
I recently had a ground fault that took me hours to find - and it had been there, undetected, for 40+ years.
A new UPS indicated the ground fault - and started the hunt.
On my electric furnace (20 kW) one of the hots got loose. Furnace still worked - but the arcing melted the connection block - I had to replace that and some adjacent wires that got damaged. I now torque that each fall before the heating season.
Another great video. Electrical systems initially are pretty straightforward but there is a bit of nuance to them to really get a good understanding of them and understand why particular codes are there.
A good example was Paul's LED video. So much more nuance to it than I thought.
one of the best videos i have seen explaining this. this should be a mandatory watch for every apprentice. great video!
I installed an AF/GFCI breaker in my kids bedroom for those exact reasons. Maybe they accidentally poke an outlet or maybe they damage a cord using it as a rope.
I found it informative and the graphics are useful for a newbie.
Amazing content for Electrical Engineer in MEP love your channel help me with the NEC
Basically, in the American system, the breaker also protects against ground faults for indirect contacts, which are the statistically most dangerous faults...for direct contacts and neutral-to-ground faults we use the GFCI.
We in Argentina use both GFCI breakers and the regular brakers. You don't need a ground wire nor grounded rod to activate the GFCI breaker, because if you touch a live wire or a (metal) fixture that has a hot wire touching it in a fouled way, your body acts as the path to earth. This event doesn't kill you because the current gets interrupted before reaching 30 milliamperes (which are considered deadly).
The real use of the Grounded rod and the ground wire is to prevent fires when an electric arc occurs between the hot wire and the neutral wire (they need just 300 milliamperes to happen, that can't be detected by the regular breaker.
You just need to connect the GFCI breaker in series with the main braker, and the whole electrical installation is protected.
En realidad no es asi, el diferencial de 30mA que decis vos solo te protege ante el contacto indirecto, para que si tocas la chapa metalica energizada haya una tension de contacto maxima de 50V en el momento de la derivacion con una resistencia de suelo menor a 1660 ohms (50V/1660 ohm=30mA)... si tocas el vivo desnudo y descalzo (contacto directo) te aseguro que por ley de kirchoff recibiras mas de 30mA y lo unico que te "salva" de morir es ese pequeño "lag" o "tiempo" que tarda en activarse el diferencial que son entre 15 a 20 milisegundos. Es un error comun creer que el diferencial es un limitador de corriente mas bien es un limitador de tension de contacto.
PLEASE MAKE A VIDEO ON POWER FACTOR,IT IS NOT WELL TAUGHT ON ANY OTHER TH-cam CHANNEL.
LOVE FROM INDIA ❤
God bless you people! You make great videos ( like most uk, us and german videos) must be something in the way saxonic languages are structured that makes your thinking so logical and clear.
8:09 wouldn’t the current on the neutral still remain the same (0.6 amps) because the lights resistance remains the same?
Excellent video
Great animations!
Thank you! I learned a lot!
Thank you very much for amazing videos! Would you be able to make a video of how low water cut off work on boilers?
Amazing useful info as usual, Could you consider creating a future video on wide band-gap SiC/GaN devices for power applications?
GFci and rccb/rcd have similar function right?
thank you for the training sir
Hey, love your videos! I have a request if you have a request/suggestion box? Not related to this particular video though, but here goes: It would be cool to know why we can use a 3 phase motor with a capacitor to power a 1 phase load 230V. How does the 400V between phases become 230V just because you put a capacitor between 2 of the phases?
I don't understand the purpose of the GFCI outlets. Isn't there already a 30mA differential breaker in the main electrical panel? I am French so I wonder if this is not the case in America.
North American breakers don't have the 30mA differential breaker, or what we'd call GFI or GFCI, that's common or required in Europe.
A lot of European service panels have RCD's built into them, which as you said trips around 30mA and protects any circuit breaker connected to it, so the need for GFCI would be indeed redundant. On the other hand, North America does not have RCD's built in. The standard service panel in North America has a main breaker, the circuit breakers - which are only there to prevent the wires from receiving more current than they're rated for, and then the busbars for neutral and ground. So unless you go out of your way to install breakers that have arc protection and/or ground fault protection, there is no protection for the people, only for the property. Hope this helps!
Gfci monitors between current going out vs returning on neutral. Its possible for current to leak out of a circuit but also have enough impedence not to short out completely. You could become a "load" and a normal breaker wouldn't know the difference. Thats why they are required around sources of water like sinks or pools. If current leaks into the water and finds another path to ground the GFCI will see this difference in return current and trip.
@@Kanis5000 this doesnt really answer their original question, they were confused as to why gfci outlets are a thing because they thought all service panels had a rcd by default.
They act as a superquick breaker right there at the GFCI outlet...not only do you have to worry about the energy exposure to the current across the body, if current travels across the heart, the heart can be thrown into arrhythmia and cause a heart attack. The GFCI instantly trips to minimize that travel time to the normal circuit breaker (the normal breaker won't even heat up) and exposure to minimize the shock risk. That's what they are really intended for.
Can you make a video where you show how to wire a normal alternator to in this case a tractor where the positive is running in the chassis
My question is: if the effective ground fault current path completes the circuit in a normal fault current situation how come that instant increase in current trips that branch circuit breaker first and not the main breaker or all the breakers for that matter? Since A/C is flowing back and forth and the low resistance of the EGC causes such high current wouldn’t the direction of current flow-at least for a brief moment-bring that high current through the main breaker and onto the bus bars it protects which would trip everything?
The branch breaker has a lower threshold, it should therefore trip first. If it doesn't, the main breaker should trip shortly after, depending on the size of the current passing through it.
@ wow! Thanks for the snappy response.
It would be wonderful if you could create a video explaining how to troubleshoot and comprehend electrical circuits
Thanks for the excellent video. What is behind the increased resistance of the ground wire/rod route compared to the neutral wire route? Is this just due to increased resistance of dirt compared to a copper wire? Thanks
the GROUND path from building to pole is just dirt, you know dirt is very bad on conducting electricity, but resistance varies depending on soil conditions like rains or illegal discharge of pollutants that contains heavy metals
@@uranium_chunkisn't that tt? i think tn-s is better
Every substance has conductivity. Soils/dirt just happen to have a very poor conductivity.
What happens when testing a resistance or continuity with a multimeter in a live high voltage circuit??
Sir can I install a piece of power capacitor at home to maintain the voltage drop the value of the capacitor is 450v 3kvar
Please make vedio on 04 to 20 milliamp signal use in instrumentation.
I love 💕 your all vedios
oh wasn't aware the GFCI isn't a very regular thing .. i don't really understand the difference between a GFCI and an ELCB (we call it FI falut current indicator often called main fuse by non electricians) or is it the same thing?
an elcb is obsolete because it only detects current in the earth wire unlike an rcd
5:17 Hah, this is allowed or even required in a lot of European countries. Obviously in this case residual current device(gfci) on all circuits is mandatory. We have panel mounted ground fault only breakers here, the standard overcurrent breakers are downstream from it, as far as I can tell the US only has combined ground fault and overcurrent available? Would be very expensive to fit a whole panel with that though a lot of Western Europe is actually doing that.
Please do make video in vacuum circuit breaker
Please do make video in acb and vcb
how you create animation in this video? it's great. what tools for made it?
is there some benefit, other than redundancy, for installing a gfci for every outlet instead of a central rcd like in europe?
Lower sensitivity
@@jm036 i guess that's nice but why not add something like a central 50mA rcd (or whatever would the 120v alt be) for redundancy? is there some reason or just not implemented
GFCI for every circuit not every outlet?
Good
Can you make a video about inrush current.
Please see our clamp meter video and circuit breaker video
Sir, I want to talk to you personally because I have many doubts to ask, how can I do so?
Bro can u do a diagram for the Davey XP25P8 Pressure Pump with 8LT Pressure Tank plis, i need to know the wiring inside out
Great and accurate videos.
Please check the definition in the NEC of "outlet"..
Please correct to "Lighting outlet", "receptacle outlet"....
Panel Breaker tripped in a certain layout, it's a bit more complicated than this.
I am subscribed to this channel and TH-cam is not showing this video in the feed, even after 3 days.
This popped as a suggestion only because I was looking at some other grounding related videos.
How would you have 600A on a ground fault if the main breaker is maybe 100 or 200A?
Fault current is instantaneous, the circuitbreaker is lowest rated so should trip first, if for some reason it doesn't then the main breaker should and if that doesn't then the transformer fuse should pop
That is a good question to ask. The reason that the downstream breaker trips first is this: Every overcircuit protection device (whether a breaker or a thermal fuse) takes a certain amount of time to react. A typical breaker/fuse will trip nearly instantly when a massive overload happens (think >5x the rated current). A more modest overload, like 2-3x, may take several seconds to trip. So a 600A fault current on a 200A breaker would take seconds to trip, while the downstream 15A breaker will trip instantly because the 600A is _far_ in excess of its instantaneous trip threshold.
(In the circuit breakers used in electrical panels, two distinct mechanisms can trip the breaker: a thermal mechanism acts slowly, and is for modest overloads. It trips once it gets hot, which is why it acts slowly. A very modest overload can take many minutes to trip! The second mechanism is magnetic. The current flows through an electromagnet, but at the rated current (and a few times above, e.g. 5x), the magnetic field it causes is too weak to trigger the breaker. But a large fault current causes a strong magnetic field, which instantly trips the breaker.)
Thank you @tookitogo and just to add that, we have shown this is a previous video (Based on Din rail breakers) th-cam.com/video/gqEu9t8HwW0/w-d-xo.htmlsi=crCY59fy_QpK6EJE&t=812
The main breaker limits what amperage to cut power at. The circuit, wires and breakers, themselves can experience thousands of amps or any other amount they just won't be able to handle it and melt.
Question for you electricians who are smarter than me.
I have a friend who lives in an older home with old wiring. It has a fuse box and with no appliance ground wires in their home runs. Short of rewiring the home (which will be done in the next year or so), is there a difference or reason for using a GFCI receptacle vs. just a regular 3-prong receptacle? How would you recommend a temporary work around?
Thanks in advance!
a gfci outlet is basically an outlet with a built in 5ma rcd
I've heard of arc fault detectors in English speaking countries, but have never heard about their existence in my region (Belgium, Netherlands, Germany, France).
With regards to earthing, are these systems called the same in the USA? TT, TN, TNC-S, IT?
Yes, it's called AFDD (arc fault detection device). And you can get combined breakers with rcd and afdd from 6-40A(eaton), 10-32A(schneider). Ofc other producers have them aswell.
so normal circuit breakers only trip if there is short circuit but if the path is between the body it will still be lethal. while gfci could detect current difference between hot and neutral even when the body with high resistance is passing current, so it will trip on ground faults. circuit breakers saves electricity bill and also fire hazards while gfci saves electrical hazards
Electrical engineer here: Circuit breakers trip based on either 1. max current or 2. average current over time.
1. In order to measure max current, the breaker has a small electric magnet powered by the current flowing through the circuit. The magnetic force is porpotional to current, and at a set point, it is stronger than a spring, tripping the breaker.
2. Average current over time is measured using a bi-metalic coil. As the coil heats up, it starts to unwind, and at a set point, it is stronger than a spring, tripping the breaker. An important note is that the current creates a constant rise in temp that eventually reaches equilibrium with the surrounding area. This means that if you have multiple overloaded breakers close together, the rated average current will go down.
Gfci breakers (ground fault circuit interupt) used the same principle from #1, but instead of a spring, it uses the return path of the circuit. If power is divert from the return path, such as whe a person gets shocked, the break trips.
Hope this helps.
Edit: phone lagged and posted mid writeup
So in a standard non gfci outlet, is it normal to have an arc happen when plugging something in? I ask because my slumlord insist this is normal.
This could be normal in GFCI receptacle or regular receptacle as well. Plugging in a tool or appliance with the power off (tool or appliance) will prevent this problem. If the receptacle is old and/or not gripping the cord very well, you should change it. Check the plug condition also.
@@surferdude642 thanks this helps a lot.
It often is normal. With electronic gadgets (which use modern switch mode power supplies, like phones, computers, TVs, etc), plugging them in charges a capacitor in the power supply. This is an instant huge current. Most of these devices don’t have “real” power switches, so when plugging in, you’re always plugging it in “hot”.
Similarly, larger appliances with motors or heaters can also spark if plugged in while turned on.
In all cases, the size of the spark depends on when in the mains waveform the connection happens. If it’s right at the zero crossing, nothing happens, if it’s right at the peak of the sine wave, the spark can be much larger. Since that happens 100/120 times per second (both halves of the 50/60Hz line frequency), it’s random to the naked eye.
You can always eliminate sparking by using a switched power strip in between, and only plugging in with the strip switched off.
@@tookitogo Good information, you're right about TV's, computers, etc., and they are normally plugged into surge protectors/power strips and left plugged in all the time, so sparking would not be an issue.
Very short momentary arcs are normal as only voltage is required to start at arc but when amperage is added and there is a suatained distance between two points is when it becomes dangerous. The amps will sustain and increase the power of the arc depending on how many amps. The amperage is determined by the load draw but as long as you don't have something big on when you plug it in there should be low risks.
Another banger.... Sorry used the wrong breaker for this comment...lol
The ground rod from the transformer to earth is frequently BROKEN in urban areas.
I mean, if you have full ground fault protection on the whole electrical system (like the UK electrical standard), both are equally dangerous. And much safer compared to without it.
As an electrician in America, I can tell you it sounds like a nightmare if something trips the system. Your entire dwelling loses power until it's found. Unless there's something I don't understand about that system. And this video is either old or they're not keeping up with the codes. Now, everything has to arc-fault protected, and the usual wet locations need to be both arc and ground-fault protected. Individual breakers makes it much easier to pinpoint a problem vs. the entire home shutting off.
@@snakeinthegrass7443 we do have individual over current breakers which is downstream of a residual current breakers. For overcurrent, you will always know which ones are tripping. For Residual current (ground fault), yes, you would have to flip all of them. The good news is that, for wet places, because of the standard, usually a more sensitive residual current breaker is used. So you don't have to flip all the breakers, jus guess which group it is and start there
@@snakeinthegrass7443I have pretty much the same regulations in my country (France(?). And yup, sometimes the whole house trips due to a defective device. But as OP responded, you have enough breakers to isolate the cause !
Moreover, there's a differential per neutral bar (Abt 10 circuits per bar if I'm not mistaken). Sometimes, it's not the whole house which trips
ANYONE???!!! A coil with an inductance of 500 millihenries has the current through it dropped from
20 amps to 2 amps in 5 milliseconds. What will the induced voltage be? Will it be in the same direction or the opposite direction to that of the source?
Why not just install one GFCI or any current differential detector on the main panel instead of having many on individual outlets? One in the main panel could protect all the outlets. I understand there are GFCI breaker for the main panel, but then why bother with GFCI outlets
I just moved to a new state and I didn't see GFCI in the bathrooms, so I went to the main panel, and lo and behold, GFCI right there on the main panel. I had no idea they ever did it that way. Only downside is its further away if you've gotta reset it lol
because identifying a ground fault in that system would be stupidly annoying and complex, leaving you without power throughout the house just because a lamp has poor quality electronics that leak to ground.
Also, statistically most electrocutions are due to indirect contact and the circuit breaker will trip perfectly well in that situation, modular GFCIs are more for specific situations like a bathroom or damp locations. That is the strength of the NEMA system over IEC
بقية الفيديوهات للقناة التي بللغة العربية اين هي ؟ انزلوها لوسمحتم
بحب قناتكم بللغة العربية انا زعلان بسبب عدم الانصاف في النشر للمقاطع 😢
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not in my house. i touch two wires and it sparks and nothing trips. great landlord😅 wired the whole house onto one breaker and that doesnt even work.
The algorithm is mad because you're obviously promoting dangerous things like touching live electrical wires. You should be advocating electrical safety, like Mehdi.
(/s because someone won't get it.)
Electrical engineer here: electricity is safe as long as you don't pick it. It is also wise to not question it, for the demons that live in the wire are vengeful. But the wards often hold making the ardent energy flow.
Proud ELECTRICAL engineer herw..😊
I note this video is Americanised, Just wondering how you developed your understanding of the US NEC? Any recommendations?
fuses and circuit breakers are pretty much the same
Can you also explain briefly that how a calculator works.😢
I'm here again
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Great video.
First comment 👌
Dear Sir/Madam,
I hope this message finds you well. I am currently a university student pursuing a degree in Control and Automation Engineering. I would like to seek advice from experienced professional engineers, or those who have at least had practical experience in this field, regarding a book titled "Electric Circuits," 10th edition, by James W. Nilsson and Susan Riedel. The contents of the book’s chapters are as follows:
1. Circuit Variables
2. Circuit Elements
3. Simple Resistive Circuits
4. Techniques of Circuit Analysis
5. The Operational Amplifier
6. Inductance, Capacitance, and Mutual Inductance
7. Response of First-Order RL and RC Circuits
8. Natural and Step Responses of RLC Circuits
9. Sinusoidal Steady-State Analysis
10. Sinusoidal Steady-State Power Calculations
11. Balanced Three-Phase Circuits
12. Introduction to the Laplace Transform
13. The Laplace Transform in Circuit Analysis
14. Introduction to Frequency Selective Circuits
15. Active Filter Circuits
16. Fourier Series
17. The Fourier Transform
18. Two-Point Circuits
My question is: Do I need to learn all the material from every chapter of this book in order to perform the tasks of a Control and Automation Engineer? Additionally, what steps should I take in my learning journey?
I sincerely appreciate any guidance or suggestions you can provide.
If you want to be the best in your field, get promotions and solve problems that other people can't, then yes, learn it all. You don't necessarily need to remember every part, but remember where to find the answer. Make notes, take screenshots, keep a folder of information and solutions you can look back on in future. No one is born with knowledge, it is something we acquire over time with effort.
Meanwhile Gallium Nitride adapter companies: Let's just push more high watt charging capabilities towards our adapter but we still make the connector with Hot and Neutral only without ground. Who needs ground anyway 😅
That's why USB4 or USB-C Power Delivery are pretty much fire hazards if the adapter itself don't have Grounding pin.
Clueless
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hello? did ytb do something weird to this video?
Wdym
@@Foxy_8796 low views compared to this channels average 🤔
@@blackholesun4942 Yeah, very strange right. We have upset the Algorithm gods somehow.
I am subscribed to this channel and didn’t see the video initially
Yes,me too
For all commenting angels if want a video on how a calculator works then like. So that this comment can fly away to the video editor or youtuber.😢
The person will explain briefly.
Seems to be a short
As a Frenchie, I don't know why electrical installations look so unsafe in other countries ? 😅
EU and french (NF) rules are very complicated, but I know I'm safe in every single condition ! I'm glad they exist when I've uninstalled a radiator, and the current was still live (even though the breaker was off. Turns out, it was mislabeled. I could have died 😂
Hi. Can l have your amil address
Hot wire, neutral wire, ground wire - all in yellow! C'mon, call channel "Kitchen engineer"
Likeew
Arc fault breakers are a scam
my home just has good ol' reliable fuses
They have issues, but they also save lives
@Phil-D83 they don't save lives they rob people. Normal breakers work just fine and always had. And when you replace a panel in an old house, how come there ok with not installing them there where the wiring is a hundred years old? Answer that. Afci breakers are useless and are a scam by corporations and companies that make them. They should be a choice not a requirement
Arc faults sucked 10 years ago but modern ones seem fine from my experience
Breakers are a scam. Neutrals are a scam. Switch legs are a scam. Dedicated circuits are a scam. Grounded receptacles are a scam. Splice boxes are a scam. Junction boxes are a scam. NEC is a scam.
/s
We get arcs for high voltage only
Can anyone help; I've got 2 sockets upstairs both do not have any power coming through the live, instead the neutral and the cpc are showing as constant live? Every other outlet is ok. I checked with a socket tester and the phase and earth is showing as a fault. No breakers are tripping or have tripped at all
If I plug anything into those sockets like a fan or phone charger it works