YouTube NEC bonding violation??

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Timebuilder

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I was looking at several of Mike's YouTube videos, and mixed in with the search results was this one regarding the bonding of a grounding electrode enclosure. I'm not sure if the bonding jumpers have to be the same size or greater, because of certain aspects of the installation as seen in the video, aspects which I have asked about in my posted comment.

https://www.youtube.com/watch?v=hPubuC0EzRc

I wonder if any of you think my comment was on target, or if the original poster was correct, and why?

Thanks!

Art Houston
 
Timebuilder said:
I was looking at several of Mike's YouTube videos, and mixed in with the search results was this one regarding the bonding of a grounding electrode enclosure. I'm not sure if the bonding jumpers have to be the same size or greater, because of certain aspects of the installation as seen in the video, aspects which I have asked about in my posted comment.

https://www.youtube.com/watch?v=hPubuC0EzRc

I wonder if any of you think my comment was on target, or if the original poster was correct, and why?

Thanks!

Art Houston
Click to expand...

http://ecmweb.com/bonding-grounding/grounding-and-bonding-part-1-2?page=3
 
MasterTheNEC said:
http://ecmweb.com/bonding-grounding/grounding-and-bonding-part-1-2?page=3
Click to expand...

Now you are talking about effectiveness. That isn't what I am asking about.

Reveiw the conversation I had with a poster below that video. I posed several ideas that he did not address, and so far, have not been addressed here.

If someone has insights to the points I made regarding the apparent "conditions" mentioned in the relevant paragraph, I would like to hear them.

I would particularly like to hear from someone who has seen similar installations shown on stamped plans, and hear what they say about the code paragraph.

Thanks in advance.
 
Timebuilder said:
Now you are talking about effectiveness. That isn't what I am asking about.

Reveiw the conversation I had with a poster below that video. I posed several ideas that he did not address, and so far, have not been addressed here.

If someone has insights to the points I made regarding the apparent "conditions" mentioned in the relevant paragraph, I would like to hear them.

I would particularly like to hear from someone who has seen similar installations shown on stamped plans, and hear what they say about the code paragraph.

Thanks in advance.
Click to expand...
Can you post what exactly was not addressed....maybe your questions where addressed but got lost in the message of what you specifically are asking.
 
MasterTheNEC said:
Can you post what exactly was not addressed....maybe your questions where addressed but got lost in the message of what you specifically are asking.
Click to expand...


If you visit the video link and look at the conversation in the comments section, you will see where I am going with this.

Ideally, one of the code committee guys will know the history behind that paragraph, and can speak to aspects such as the mention of cabinets and equipment, as opposed to simply saying that ALL ferrous metal enclosures for GEC's must have a same-size bond at each end.

To me, it is not intuitive whether or not they are trying to keep an induced voltage out of equipment, or merely limit GEC impedance. Is the need for a same-size bond conditional on the connection of the enclosure to a cabinet or equipment? It is not sufficiently clear to me just what their intent might be.

I would love to know if the installation shown in the video came from a set of stamped and approved plans, too.
 
Timebuilder said:
If you visit the video link and look at the conversation in the comments section, you will see where I am going with this.

Ideally, one of the code committee guys will know the history behind that paragraph, and can speak to aspects such as the mention of cabinets and equipment, as opposed to simply saying that ALL ferrous metal enclosures for GEC's must have a same-size bond at each end.

To me, it is not intuitive whether or not they are trying to keep an induced voltage out of equipment, or merely limit GEC impedance. Is the need for a same-size bond conditional on the connection of the enclosure to a cabinet or equipment? It is not sufficiently clear to me just what their intent might be.

I would love to know if the installation shown in the video came from a set of stamped and approved plans, too.
Click to expand...

The NEC has a requirement for bonding at both ends of a ferrous enclosure (including both raceway and sheath) of a GEC for one major reason:

The ferrous enclosure with the GEC running through it will form an inductor (choke) with the single turn of conductor linked to the ferrous "core".
This will reduce the capacity of the GEC to carry high fault currents at 60Hz. but will have an even greater effect on the high frequency currents associated with lightning.
To avoid the choke effect you have to allow the entire current (well maybe 90% or more) to flow through the enclosure instead. The effect is vaguely similar to the skin effect seen on large conductors carrying AC, but the details are very different.

The same requirement does not apply to an EGC. But the EGC is required to be in the same enclosure with the grounded and ungrounded conductors, so for any fault involving only that circuit the net current will be zero, so no choke effect.
 
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Timebuilder said:
If you visit the video link and look at the conversation in the comments section, you will see where I am going with this.

Ideally, one of the code committee guys will know the history behind that paragraph, and can speak to aspects such as the mention of cabinets and equipment, as opposed to simply saying that ALL ferrous metal enclosures for GEC's must have a same-size bond at each end.

To me, it is not intuitive whether or not they are trying to keep an induced voltage out of equipment, or merely limit GEC impedance. Is the need for a same-size bond conditional on the connection of the enclosure to a cabinet or equipment? It is not sufficiently clear to me just what their intent might be.

I would love to know if the installation shown in the video came from a set of stamped and approved plans, too.
Click to expand...


I understand the theory of the choking effect. That's not what I am asking about.
 
Timebuilder said:
I understand the theory of the choking effect. That's not what I am asking about.
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It's probably best if you forget the link and your conversation there, ask you question here with the specifics of what you don't agree with or understand.

Roger
 
roger said:
It's probably best if you forget the link and your conversation there, ask you question here with the specifics of what you don't agree with or understand.

Roger
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Roger are you saying that the only intelligent individuals in the electrical industry inhabit this forum and don't venture over to Youtube?:angel:
 
MasterTheNEC said:
Roger are you saying that the only intelligent individuals in the electrical industry inhabit this forum and don't venture over to Youtube?:angel:
Click to expand...

Why of course I am. JK :D

I just think it would be easier and less confusing to have the specific questions posted here.

Roger
 
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