Grounding Versus Bonding (26min:26sec)
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- Опубліковано 15 лип 2024
- Visit www.MikeHolt.com/14code to explore Mike's complete range of 2014 NEC training products. For over 35 years Mike Holt Enterprises has specialized in providing quality training products for Exam Preparation, Continuing Education & Code Training for the electrical industry.
This clip is extracted from Mike Holt's Illustrated Guide to Changes to the NEC 2014 DVD Library
![Grounding, System and Equipment [250.4, 2020 NEC]](http://i.ytimg.com/vi/lyD6gzEze68/mqdefault.jpg)
![Transformers - Understanding Delta/Delta Connections [250.4(A)] (26min:36sec)](/img/n.gif)
I have been an electrician for 15+ years and we need to have, share and exchange more quality information like this. UA-cam is supposed to be like this, a place where you can learn. Thanks Mike holt for sharing your knowledge.
Yeah sad thing is is that co-workers still laugh at u when u get zapped. I remember the first time I tasted a little bit higher voltage than 120 it was just across 2 legs of 208 and It caught me on the soft spot of my forearm (it was a piece of emt with wires hanging out that looked like an abandoned circuit) that was a bit of a different level lol I could feel it pulse through me and my coworker laughed at me the rest of the day lol.
Mike Holt is a national treasure
A living example of the spirit that built the nation, the shoulders we stand on today
This is my humble opinion after watching many of his videos
Thank you sir
Everything about that cute little ground wire every time I watch this has me dying. I can't get enough of it.
I'm watching this 2 years later and I'm dying too!
lol!!!!!!!!!!!!!!!
Are you guys dead yet 🤔
You ate the man, Mike. Thank you for all of your masterclasses.
Fascinating, changes everything that I thought I knew. Thank you Mike Holt!
I was just looking for guides on how to create my own ground at home, but this video is very informative and fun to watch. Thanks for the info!
much respect but the freak out at the end is comedic gold.
FINALLY, a discussion that assumes an elevated working knowledge of electricity in the target audience. Thank you. I'm resigned to listen to all your videos after ten minutes into this, my first one.
You are most welcome.
Hands down, the best presentation on the subject that I've ever seen.
Thank you!! Sparks in Daytona
Thank you but watch - studio.ua-cam.com/users/videompgAVE4UwFw/comments
Thank you for sharing your knowledge
Thanks for the thoughts you have contributed here.
When he went off the rails and sarcastically ranted about NASA grounding their rockets I couldn’t stop laughing 🚀 Seriously though, when someone is PASSIONATE about what they say it becomes natural to listen and learn from them. Mike Holt knows his stuff and truly educates millions. You make the world a safer place Mike!
LOVE THIS !!!!
Very instructive seminar of 08/25/2018. 6:40 hours fully loaded. Thanks Mike
Thanks, you must have been at our NYC seminar! We had a great time with everyone!
Great video and a point about Defibrillation stops the heart from fibrillating, think of it like rebooting the heart and letting it naturally regain a rhythm. It is a single shock rated in joules. It is not multiple pulses. Multiple pulses would be external pacing which would increase the heart rate but not typically used to restore a normal sinus rhythm
Thanks for the additional information.
I absolutely love this! I've learned more in this video than in class
That's what I'm talking about! I love making a difference in the lives of others. Thank you for letting me know this video made a difference.
Mike. Your video was great explaining grounding in an electrical system.
Thank you.
Nice one I'm Avid fan of your video
Thank you!
Those rods on poles, lights and even signs in FL are to protect pedestrians etc. Almost everything metal outdoors has a rod in FL now. You were on the right path when you got all emo talking about the ground rods around the shuttle pad. Lively video. I learned alot.
+patrickwelch
I have no idea what you are talking about.
Another guy is saying you can't have too many ground rods. Of course you want everything in one path with a full return. But then how many bonds before a surge buildup. A whole city on one bonding circuit doesn't sound good either.
very good information
the 30 volts and 15 volts for electric shock and hazard from death comes from the amperage that is required to stop the heart and using ohms law and an assumed resistant in a persons body is where the 30 volts comes from. I believe 0.1 amps can cause the heart to stop so assuming a person resistance is 300 ohms 30 volts could kill someone.
Thanks again for fighting electrical ignorance! Little do people realize that that rebar cage IS a very effective ground. Heck, even the concrete itself is considered ground. CEC allows one to encase their grounding electrode into concrete - can't site the rule atm..
250.52(A)(3)
I would have subscribed when I finished college in 1990, I liked the video kudos
So this would be the reason the Neutral and the ground would be connected in the main panel ( not in a sub panel ) , or would go back to the a neutral bar, to clear a ground fault ?
So when put up an 20 ft ham antenna mast, I live in a mobile home, they advice to use a 8 ft ground rod to ground the mast. The ground of the coax should be bonded to the metal frame of the mobile home which is bonded with the power box in my home which is connected with the ground rod at the electric companies power box 25 feet away. It does not feel right somewhere. Any advice please?
Thank you for the quality videos. Keep it up. There is. Still plenty of false info out there!
STEVE HOLT!
I'm afraid to flip my light switch after watching this but thank you for the heads up to this diy'r
Yea really...
Please watch this video ua-cam.com/video/mpgAVE4UwFw/v-deo.html
@@mikeholt3717 ⁰
My midddle school electric shop teacher test hot circuits with his fingers.
Some places require the earth as the return. Some utilities use SWER system where the earth is the neutral, it saves them the money of running a second wire for the neutral.
Correct, en.wikipedia.org/wiki/Single-wire_earth_return
Need some instruction on concentric bends, please!
Thank you!
Just search the Internet and you'll get all of the info you need.
When there is current through the human body, it is not necessarily electrons carrying the current. In some cases, it is positive sodium ions, like it is in our nerve cells.
***** Certainly, Mike.
This is where I first learned about it:
amasci.com/miscon/eleca.html#frkel
The page discusses the "accident" that Benjamin Franklin made by arbitrarily picking the sign convention of charge. It may frustrate the teaching of introductory electricity, when our convention of current flows opposite the electrons. But what it really did, was force us to confront the problem of understanding "current" in a more generalized sense.
Had he picked the signs to eventually make a positive electron, we'd complacently teach that current is the flow of electrons. The directions of each would be the same, and we wouldn't be prompted to separate the concepts, to think that current could be carried by something other than electrons.
It may not necessarily be electrons carrying the current. But rather anything with charge. Usually the body with the least mass, that can freely flow. Current flows in the direction that an equivalent flow rate of positive charge would flow, to create the same electric/magnetic field effects as which ever charge actually flows.
Perhaps this is the way AC enters the body?
Fib-rih-lay-tion
De-fib-rih-lay-tor
The heart consists of millions of electrical cells that charge and discharge. The heart is controlled by the brain.
The heart has its own electrical pacing system. Theoretically, if you unplug the brain/heart connection but keep oxygenated blood flowing to the heart, it will beat on its own.
The heart has 3 pacing sources, 1 normal and 2 escape (backup) systems.
The normal pacing signal is given by the Sinus node located in the Atrium (the top half of the heart). It’s rate is 60-100 beats per minute. When the signal comes from the Sinus node at a rate of 60-100 it is called a Normal Sinus Rhythm (NSR). Slower than 60 from the Sinus node is called a bradycardia. Faster than 100 from the Sinus node is called a tachycardia.
If the Sinus node is damaged from tissue or electrical damage (lack of oxygen via clogged artery or electrical shock) the heart will go into an Escape rhythm.
The first of the 2 Escape rhythms comes from the middle of the heart and is called the Junction (Junctional rhythm). The junctional escape rate is 40-60 beats per minute.
If the Junction is knocked out, the last escape rhythm comes from the bottom half of the heart called the ventricle. This rhythm is called an Idio-ventricular rhythm and the rate is 20-40 beats per minute. In the medical world it’s simply said to be an idio rhythm.
The top and bottom half of the heart do not beat at the same time. Mechanical action occurs when the electrical system sends the signal to the cells. The normal discharge recharge cycle goes like this:
Atrium-discharge (muscles contract and blood is pumped into the ventricle filling it up).
The electrical signal sent by the Sinus node when it fires off travels to the ventricle, but it is intercepted by the Junction for a very brief moment, held and immediately released to continue on its way down to the ventricle.
Recharging of the atrium begins.
Ventricle-discharge, atrium recharge completes.
Atrium - discharge, ventricle - recharge.
Repeat 86,400 a day.
When you are electrocuted ALL of the electrical cells in the heart discharge at once and there is no recharging. The entire pacing system is knocked out and the electrical cells in the ventricles begin discharging in total chaos. The ventricle is a quivering mass at this point. No blood is being pumped.
A defibrillator discharges all the cardiac electrical cells at once and hopefully the Sinus node will step up and take over the electrical system again. After the defibrillator fires off, the first thing everyone does is look at the monitor screen to see if the electrical waves have changed out of ventricular fibrillation.
If the heart returns to a viable rhythm (NSR is the ultimate goal) the term is Converted. “He converted back to Sinus”.
If you survive an electrocution, you most likely will suffer permanent damage to your cardiac electrical system and suffer from various dysthymias for the rest of your life.
You are amazing, how do you know this to be true?
MikeHoltNEC I was a Paramedic for 36 years. Now I’m a Firestopping Inspector.
The only problem i have with equipment grounding conductors is they have the potential to route lightning directly into your panel box. Any steel frame structure with steel siding beams and collumns is an equipment grounding conductor itself. Metal raceways should be used to limit the use of individual equipment grounding conductors and to save on copper. When the huge metal building gets struck by lightning it will track thru the columns and footings and will be diverted from the main electrical distribution center.
I think this is just an opinion not based on any study that supports your statement. Wiring with EGCs have been done for about one hundred years... Please provide facts next time you make a post.
Sorry if i look dumb saying this , I'm new and on the process of learning to become an electrician... So the difference here between grounding and bonding , is that grounding is a myth? Using ground poles won't really protect you from high voltage? The bonding part is more effective , because you bond the ground to any metal type part and bring it back to the source so it can trip? If anyone can be kind enough to correct me if I'm wrong. Thank you.
This is correct, but also watch ua-cam.com/video/mpgAVE4UwFw/v-deo.html
You're not dumb at all. Ground is the most important concept to understand while also being the most difficult. Ground is the medium through which the power system returns electrons to the source (not necessarily true for AC but this is a fine analogy for most applications). Bonding is creating equipotential connections at each piece of equipment (accounting of course for voltage drop). Grounding is very real and necessary. In principle, Ground should be referenced at only one point from bonded conductors. There will circulating currents and issues with protective devices otherwise (specifically microprocessor based relays and such).
Ground poles will not protect you from high voltage if they are shorted. In a broad (not "totally" true) sense voltage will be forever the same if it's connected to a ground conductor before reaching the load (if it's shorted). If you connect a ground rod to the positive secondary lead of a 7200/240/120 transformer the voltage at the meeting point of the rod and the conductor will be +120 volts... always. The point of grounding is to carry current to a protective device (breaker, relay, fuse) that will clear the fault by opening the circuit (loop). In a substation, relays are installed looking at a proportional ground current flow. If it measures something over 140 Amps on the ground conductor, the relay will open the breaker.
Ground will not make things safe. It is a means by which things can be made safe. It's for this reason I don't agree with Mr. Holt in that grounding doesn't make things safer. It does. You can't clear a ground fault without an appropriate ground path of return. The myth Mr. Holt is (correctly) trying dispel is that grounding is all that is needed to make things safe.
Bonding will make things safe because bonding will eliminate large potential gradients. It will place things (metal, ground rods, metal equipment casings, soil) at the same potential, whether that's 2V or 250,000V. So long as the voltage difference is kept at a minimum, current will not flow in amounts large enough to cause harm.
I would recommend the IEEE Green Book if you want to have a complete understanding of grounding in a Power System.
Tyler Minix that’s so interesting.. so the guys servicing high power lines, on helicopters, when they use that rod, is that actually bonding?
@@Lazdinger Yes, that's correct.
The incidence on page 1:20 may be avoided had transformer winding are floating off the ground. So what is the benefit of grounding networks upstream?
That is not the system grounding we use in the USA. See MikeHolt.com/Fundamentals.
Is there any program like this for the Canadian code
Not that I'm aware of.
Acoording to you 25 second 40 amp going though body will kill heart then isnt that too long breaker to trip Mike ? Ark fault current intrapter shut off faster?
When I see other test by easton ir levinton they open by 1 second by shortening wire I think those chart are way off?
Moto Back to constitution what you all be sayings , yo?
No, since a ground fault is not an arcing fault.
@@MikeHoltNEC 25 second 40 amp is too much for body
..the distribution transformers have earth the neutral outside, why do we need to ground/earth it again indoor..?
Sooooooo? Don't stick the fork in the wall socket?
plz make a vedio on how to size breaker and if there is kindly tag me there @ Mikehotnec
Isn't the ground rod for lighting too?
Please watch this video - ua-cam.com/video/mpgAVE4UwFw/v-deo.html
Back to source ? . source on poul , nutro is connected at transformer on poul connected to earth ground anyway right so whats the deffarence ? Its going same earth ground
Watch the video again.
A lot of good info here, but I couldn't help but laugh my a$$ off.
Lol...
Where do I go to buy ur electrical exam busters
That's a great way to describe our product. Please call 352.360.2620 and my staff will 100% get you taken care of. Visit MikeHolt.com/Exam first so you know your options!
Isnt nutro going to earth gound at end?
Watch the video again.
22:31-22:33 LOL.
So a bonded propane furnace with an underground tank will always have at least two different ground locations per structure?
Nope. And I don't understand what you are saying.
@@MikeHoltNEC gas furnace or boiler grounded via ground wire to stake by meter , also grounded by copper piping at tank via gas line . Two different ground locations, potential for stray voltage, no ?
@MikeHoltNEC not directly related to this video, thought of your lecture from a few years ago
@MikeHoltNEC you actually got me interested in the biological effects of earthing. Really changed my life . Thanks BTW
@@mikepict9011 Just follow 250.104(B), which effectively says to do 'nothing.'
At 21:11, you mention it is a practice to *not* have an EGC. If this is the case, then I assume there is no ability to clear a fault. So does this mean someone needs to get shocked (or less commonly die) and report the problem to the city government to fix the fault?
Yep...
at 13:46 when children insert keys, oh my gosh
It's a one time single event, don't ask. Same feeling as holding on to a firecracker, YMMV.
That's current
Great video, except for a tiny bit of baloney between 10:01 and 10:16. Electric shock / fibrillation has nothing to do with the frequency, or how it matches with our "body frequency", also, our body DOES NOT run at 40Hz, we have various systems in our body, which run on various frequencies, which vary with time as well. The only part of frequency that is relevant to electric shock has to do with the penetration. For example, an RF signal frequency is too high to penetrate deep into the body to cause electrical shock, you'll get a burn instead. As long as the frequency is low enough, you'll get a shock and if the current is high enough you'll get fibrillation. If the frequency is high enough, you'll get a burn instead.
Also the body has a capacitance which can be penetrated much easier by AC than DC. Therefor the higher the frequency the lower the capacitive resistance the higher the inductive resistance. ANd therefor in between the two you will get shocked.
Alec Kristi. prove it.
26in:26sen...????? What is that means??
Typo, should be minutes
Also that "cute little wire" is not for lightning protection. It is to bleed of induced voltage to ground so anyone touching that pole won't get lit up (or dogs peeing on it as described in your grounding myths videos).
+Max Koller The pole is connected to 12 very large bolts that are probably 12 - 15' in the concrete cage; any induction on the metal pole is take care of by the inherent grounding of the metal pole to the concrete base.
Yeah that is enough, but I think this is more for the regulations than actual use. (Got to meet those regs).
Voltage cannot "bleed off."
@@MikeHoltNEC My money is one that "Ufer ground" is better than that "cute little wire" for bleeding off "induced voltage".
Oh my goodness!! I cannot believe I just sat here and listen to a grounding and bonding video from Michael and had spent the entire video talking about electric shock give me a break!!!!
I'm a little thick headed. I think this is the 'BIG MESSAGE'.
15:48 "…So the concept of providing protection to people is to make sure everything that’s metallic is connected to an equipment grounding conductor. And we have to make sure that all of the equipment grounding conductors are connected ultimately back to the equipment grounding conductor at the source, which is going to be your grounding terminal and we have to make sure that we bond that equipment grounding terminal at the transformer to the system itself via the system bonding jumper.
If you provided proper equipment grounding conductor, proper termination, proper connection all the way back to the source, that equipment grounding conductor, that supply side bonding jumper, that system bonding jumper and all those interposing connections back there is called the effective ground fault current path, and that’s how we get the electron from that fault back to the source to open up that protection device (the breaker). It’s that simple… Make all the metal parts connect to the equipment grounding conductor, connect it back over to the equipment grounding conductor at the source, connect the source over to the neutral, badda-bing badda-boom, we’re done. "
Right I believe this is why the ground and the neutral wires are connected to the neutral bus bar, so the equipment ground has an opportunity to return the ground faulted charge back to the source .And why you do not connect the ground and neutral in a sub-panel , because when the neutral is charged ie. carrying current back to the source ie. the main panel , , the ground wire would also become charged .
Its funny and sad how lot of engineers and tecnics think a ground rod solves all risks of fault current or electrocution.
23:40 - 24:14 lol
110 tickles..
277..well it doesnt feel good at all 😲
120V kills, it does not tickle...
Voltage doesn’t push the electrons. Voltage is not doing the work. I get your concept but it’s technically false and wrong information.
Interesting comment… do you have anything to support your statement or is this your opinion.
@@MikeHoltNEC Yes, sorry for not including that. Voltage is not a force. Therefore could not possibly place a force on anything. Voltage is a scalar. It’s only a magnitude of difference in charges. A force is a vector, so it has two things.. magnitude & direction. Voltage does not fit that definition. I don’t mean this in any mean or offensive demeanor. I love your work, videos, programs, etc. I’m a fan and co-contributor to making sure the proper information is relayed to our electrical industry. United we stand!
Thanks, so you have nothing to support your ‘opinion.’
@@MikeHoltNEC Mike with that logic I could ask you the same thing. Let me know when you prove that voltage is a force, so I can be there when you win a noble peace prize and change physics forever 😂😂
@@Electric_Sherlock Okay, so you understand, my statement that Voltage is the Electromotive Force (EMF) that pushes and pulls electrons in a circuit is what is written in every book on the topic. If you find something that says that Electromotive Force (EMF), as measured in volts, is not the pressure to move electrons in a circuit, please give me the source. I'm not trying to be disrespectful, I just want to have the facts you have on the topic that I don't have.
This information is wrong. For one, it assumes that facility ground and power neutral are the same thing. All his models are based on this. Neutral and ground should NEVER be tied together other wise we are back before we had three pong electrical outlets. Poles are not supposed to be grounded it is the lightning rod at the top that is and it should be electrically isolated from the pole to create a 30% cone of protection. If you do not protect a metal pole that goes into concrete if lightning strikes it the instantaneous heat created by the strike will super heat the concrete and blow up the foundation that holds it up. This man is ludicrous. I guess this explains a lot of the shotty contractor work I see.
+Max Koller At the service to all buildings having a grounded system (120/240, 120/208, 277/480, the utility neutral is always bonded to the equipment grounding conductor. Lightning striking a conductive surface does not result in concrete in the slab to blow up. This is the reason the NEC almost requires the re-bar in a building footer to serve at the building system grounding electrode. If you have any documentation to support your statements, please forward to me at Mike@MikeHolt.com.
www.google.com/search?q=lightning+damage&client=ms-android-att-us&source=android-browser&prmd=ivsn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiXrrPP0-TKAhUY8WMKHYh-BTcQ_AUIBygB#imgrc=_j0AdFbJDtynXM%3A
When enough electricity to power a city for two days strikes a small location the heat energy created from resistance can instantly vaporize water/humity creating enough steam power to break/blow up anything that cannot conduct that amount if power. I will quote Einstein here energy cannot be created or destroyed only transferred. And the fastest way to do that is heat. That is why you never ground in non-conductive material.
By the way hot, neutral, and ground are 3 separate wires for a reason. If you tie them together electrically it is the same as only 2 wires. Got to get away from the 2 prong outlet of the mid century. Sorry don't mean to blast you, but I had more explaining to do to my less experienced guys than I want to do after seeing this. Like the video though it was very entertaining and it started a great discussion.
+Max Koller Neutral and Grounds are required to be bonded together via the National Electrical Code at service equipment at all building supplied by a grounded system [250.24(C)] and the load side of separately derived systems like transformers and some generators [250.30(A)]. After that location neutrals and grounds are required to be separated, see 250.142..