Is a ground bar considered a bus bar?

[Epalmateer]

I can't really find anywhere the new defines busbar. Would ground bars and neutral bars be considered busbars? If not what is your explanation?

 

[Epalmateer]

Typo "the new" was supposed to be "that"

 

[Carultch]

I can't really find anywhere the new defines busbar. Would ground bars and neutral bars be considered busbars? If not what is your explanation?

Is there a particular reason it makes a difference in your application?

Ordinarily, I would consider it a busbar, but perhaps if I had some context to the question, I might see a reason to answer differently. Busbar is to electricity, as manifold is to plumbing, in the sense that it is a device for distributing and combining current. A ground or neutral bar would certainly fit my general understanding of what a busbar is.

 

[Epalmateer]

Is there a particular reason it makes a difference in your application?

Ordinarily, I would consider it a busbar, but perhaps if I had some context to the question, I might see a reason to answer differently. Busbar is to electricity, as manifold is to plumbing, in the sense that it is a piece of equipment for distributing and combining current. A ground or neutral bar would certainly fit my general understanding of what a busbar is.

350.64 c allows for sections of busbar to connect gec

 

[Epalmateer]

Is there a particular reason it makes a difference in your application?

Ordinarily, I would consider it a busbar, but perhaps if I had some context to the question, I might see a reason to answer differently. Busbar is to electricity, as manifold is to plumbing, in the sense that it is a piece of equipment for distributing and combining current. A ground or neutral bar would certainly fit my general understanding of what a busbar is.

250. Fat finger

 

[Epalmateer]

Is there a particular reason it makes a difference in your application?

Ordinarily, I would consider it a busbar, but perhaps if I had some context to the question, I might see a reason to answer differently. Busbar is to electricity, as manifold is to plumbing, in the sense that it is a device for distributing and combining current. A ground or neutral bar would certainly fit my general understanding of what a busbar is.

Would the definition in 393.2 say no?

 

[Carultch]

250.64 c allows for sections of busbar to connect gec

Yeah, that's a tricky one that I don't know how to answer. The intent of all the remaining options, seems to be that you irreversibly splice the GEC any time it is necessary for it to be discontinuous. Busbars are commonly used either with threaded fasteners to attach lugs, or with built-in lugs on a ground bar, all of which would mean a reversible connection.

I am not familiar with what the author of this section had in mind, by allowing "busbar" to connect the GEC, and how it would allow reversible connections if at all. If you have your doubts on this one, I'd recommend irreversible tap connections only, in order to use the same GEC for multiple devices.

 

[Epalmateer]

Yeah, that's a tricky one that I don't know how to answer. The intent of all the remaining options, seems to be that you irreversibly splice the GEC any time it is necessary for it to be discontinuous. Busbars are commonly used either with threaded fasteners to attach lugs, or with built-in lugs on a ground bar, all of which would mean a reversible connection.

I am not familiar with what the author of this section had in mind, by allowing "busbar" to connect the GEC, and how it would allow reversible connections if at all. If you have your doubts on this one, I'd recommend irreversible tap connections only, in order to use the same GEC for multiple devices.

I really just want to know they had in mind. Would a definition in article 3 be valid in article 2?

 

[infinity]

Would the definition in 393.2 say no?

I say no. That definition is relative that article only. Not all bus bars are connected with insulators and not all are for power rail applications.

 

[Dennis Alwon]

This is a busbar, IMO

 

[Epalmateer]

I would agree. I think it needs to be defined in article 2.

 

[Fred B]

Just to clarify from other thread as to NEC definition or lack thereof and placement within the NEC. Been told by a member the CMPs have been in process over the last several cycles and in the coming one to get all the definitions into one location. If it is a universal definition that reoccur in multiple code sections they have been trying to get them all into Article 100. If it is one that pertains only to a singular Article or limited scope the effort has been to get all those definitions into XXX.2. This type of discussion is the primary justification to make definitions easier to find and to apply. Some things are left undefined because the feeling it is universally understood, if someone feels something need more definition been told by the member that they welcome input.
NEC 2017 indicates the use of the term "busbar" also in 230.205(D), 250.24(A)(4), 250.30(A)(4)(6),(6)(c)(2); 250.64(C)(2); 250.94(B),; 310.10(E)(F); 366.2; 366.100(E) etc.
So to answer OP all these references in 250 to busbar use for grounding I would say yes the ground bar is a specific type of busbar, but not the only type. Every grounding bar is a busbar but not every busbar is a grounding bar.
I would say the definition in 393.2 would be unique to that section as it includes special criteria such as insulation. That may also be true for other utilization of busbar in other sections.

 

[Epalmateer]

Just to clarify from other thread as to NEC definition or lack thereof and placement within the NEC. Been told by a member the CMPs have been in process over the last several cycles and in the coming one to get all the definitions into one location. If it is a universal definition that reoccur in multiple code sections they have been trying to get them all into Article 100. If it is one that pertains only to a singular Article or limited scope the effort has been to get all those definitions into XXX.2. This type of discussion is the primary justification to make definitions easier to find and to apply. Some things are left undefined because the feeling it is universally understood, if someone feels something need more definition been told by the member that they welcome input.
NEC 2017 indicates the use of the term "busbar" also in 230.205(D), 250.24(A)(4), 250.30(A)(4)(6),(6)(c)(2); 250.64(C)(2); 250.94(B),; 310.10(E)(F); 366.2; 366.100(E) etc.
So to answer OP all these references in 250 to busbar use for grounding I would say yes the ground bar is a specific type of busbar, but not the only type. Every grounding bar is a busbar but not every busbar is a grounding bar.
I would say the definition in 393.2 would be unique to that section as it includes special criteria such as insulation. That may also be true for other utilization of busbar in other sections.

Well said.

 

[Dennis Alwon]

Whenever I see or read about busbars this is what I see. Not sure how that would be defined.

1500 ampere copper busbars within a
power distribution rack for a large building

 

[Epalmateer]

Whenever I see or read about busbars this is what I see. Not sure how that would be defined.

1500 ampere copper busbars within a
power distribution rack for a large building

I mean, I think if they defined it is as something without threaded holes for the sole purpose of screw type terminals, only bolting means

 

[Epalmateer]

Whenever I see or read about busbars this is what I see. Not sure how that would be defined.

1500 ampere copper busbars within a
power distribution rack for a large building

Or say that wires must terminate terminate to it with ring type terminals

 

[Fred B]

Whenever I see or read about busbars this is what I see. Not sure how that would be defined.

1500 ampere copper busbars within a
power distribution rack for a large building

That is probably why we use more "common" terminology of ground bar vs other types that are power distribution type like shown or what a residential guy might see in a panel board for stab-on connection of breakers.

 

[Epalmateer]

Or list rules for busbars used for grounding and bonding

 

[don_resqcapt19]

Whenever I see or read about busbars this is what I see. Not sure how that would be defined.

1500 ampere copper busbars within a
power distribution rack for a large building

That is what I think of when I read the term busbar. I see the earlier one you posted as a grounding bus or grounding busbar.

 

[Dennis Alwon]

That is what I think of when I read the term busbar. I see the earlier one you posted as a grounding bus or grounding busbar.

Exactly both are busbars but used for different purposes