# 408.40 ground/neutral on shared bar



## dielectricunion (Nov 29, 2012)

"Equipment grounding conductors shall not be connected to a terminal bar provided for grounded conductors...unless identified for the purpose and located where (neutral and ground are bonded)..."

Does this article prohibit the mixing of grounds and neutrals on the same bar in a main panel?

I just heard someone claiming this but I've seen plenty of passed inspections where grounds and neutrals shared


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## The_kid (Nov 4, 2014)

dielectricunion said:


> "Equipment grounding conductors shall not be connected to a terminal bar provided for grounded conductors...unless identified for the purpose and located where (neutral and ground are bonded)..."
> 
> Does this article prohibit the mixing of grounds and neutrals on the same bar in a main panel?
> 
> I just heard someone claiming this but I've seen plenty of passed inspections where grounds and neutrals shared



In a main panel the feeder neutral and ground are bonded. You don't isolate grounds/neutrals in a main. 

I suppose the listed bonding screw would be how it's identified? I'm not sure how to interpret that.


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## dielectricunion (Nov 29, 2012)

I understand the bonding at first means of disconnection, Im just a little confused about the identification for the use of both EGCs and grounded neutrals.

If I looked into the panel/manufacturer fine print, I'm sure there's something identifying that bar for both in a bonded setup.


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## McClary’s Electrical (Feb 21, 2009)

dielectricunion said:


> I understand the bonding at first means of disconnection, Im just a little confused about the identification for the use of both EGCs and grounded neutrals.
> 
> If I looked into the panel/manufacturer fine print, I'm sure there's something identifying that bar for both in a bonded setup.


Yep exactly. You just answered your own question.


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## McClary’s Electrical (Feb 21, 2009)

Why did you leave out the last sentence? It's the most important part. 

Secondly, you don't see many panelboard s in a residence


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## dielectricunion (Nov 29, 2012)

I was just abbreviating the last sentence because I'm lazy and typing on a phone... Permitted by 250 I didn't include.

So a residential main panel wouldn't be considered a panel board? I figured it was


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## McClary’s Electrical (Feb 21, 2009)

Those are considered load centers. 


"As permitted by 250" were the key words.


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## dielectricunion (Nov 29, 2012)

I know they're called load centers, but that's not a term defined or used in NEC.

Would a load center be considered a panel board?


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## McClary’s Electrical (Feb 21, 2009)

Panel board is clearly defined. You won't see many panelboards in a residence


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## Tom Solanto (Mar 11, 2011)

dielectricunion said:


> I know they're called load centers, but that's not a term defined or used in NEC.
> 
> Would a load center be considered a panel board?


A load center is a panel board. There is no definition for load center because it is the same thing. Look at the definition of panel board. It has all the components of a load center.

*Panelboard.* A single panel or group of panel units designed
for assembly in the form of a single panel, including
buses and automatic overcurrent devices, and equipped
with or without switches for the control of light, heat, or
power circuits; designed to be placed in a cabinet or cutout
box placed in or against a wall, partition, or other support;
and accessible only from the front.


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## cabletie (Feb 12, 2011)

dielectricunion said:


> I know they're called load centers, but that's not a term defined or used in NEC.
> 
> Would a load center be considered a panel board?


A loadcenter is a panel board and cutout box all in one. 
Commercial panel boards are built separate. The cut out boxes are installed first. later the panel board is installed in the cutout box.


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## McClary’s Electrical (Feb 21, 2009)

Tom Solanto said:


> A load center is a panel board. There is no definition for load center because it is the same thing. Look at the definition of panel board. It has all the components of a load center.
> 
> *Panelboard.* A single panel or group of panel units designed
> for assembly in the form of a single panel, including
> ...










cabletie said:


> A loadcenter is a panel board and cutout box all in one.
> Commercial panel boards are built separate. The cut out boxes are installed first. later the panel board is installed in the cutout box.


You're both wrong. Check the ul listing on those panels and youll see they are not panelboards. To say both are the same is completely false.


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## Mulder (Sep 11, 2010)

mcclary's electrical said:


> You're both wrong. Check the ul listing on those panels and youll see they are not panelboards. To say both are the same is completely false.


If that is the case, 408 wouldn't apply to loadcenters.


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## Tom Solanto (Mar 11, 2011)

mcclary's electrical said:


> You're both wrong. Check the ul listing on those panels and youll see they are not panelboards. To say both are the same is completely false.


Since you mentioned UL why not actually read it. It is obvious that a load center is included in the description. 

*PANELBOARDS (QEUY)
USE, INSTALLATION AND MARKINGS*
This category covers lighting and power panelboards rated 600 V or less.
Panelboards are intended for mounting in cabinets, cutout boxes or enclosures designed for the purpose. The enclosure may be provided with the
panel or provided separately. Only panelboards marked to indicate that they
are for use in specific enclosures (identified by either catalog number or specific
dimensional information) and panelboards labeled as ‘‘Enclosed Panelboards’’
have been investigated to determine that wiring space is adequate,
or have been investigated for short-circuit-current ratings greater than
10,000 A rms symmetrical..
Enclosed panelboards identified with an Enclosure Type designation are
intended for use as indicated in Electrical Equipment for Use in Ordinary
Locations (AALZ).
Some enclosed panelboards have one or more openings for plug-in watthour
or similar meters. Such panelboards, when marked for outdoor use
have, except for the joint between the plug-in meter and opening, been
investigated for rain tightness.
Some panelboards are suitable for use as service equipment and may be
so marked. Such marking is part of the Certification Mark as noted below
or is an integral part of other required markings. Panelboards marked to
indicate that they are suitable for use as service equipment and which can
be removed from the enclosure are marked to identify the specific enclosure
in which they are intended to be installed. If the acceptability of such a panelboard
for use as service equipment depends upon the condition of installation
or use, the panelboard is marked to indicate those conditions.
Some panelboards incorporate neutrals factory bonded to the frame or
enclosure. Such units are marked ‘‘Suitable Only for Use as Service Equipment.’’
Panelboards marked for use at services may also be used to provide the
main control and means of cutoff for a separately derived system.
Panelboards are marked with their short-circuit-current rating in rms symmetrical
amps. The marking states that short-circuit ratings are limited to
the lowest interrupting rating of (1) any device installed or intended to be
installed therein, and/or (2) any combination series-connected device. However,
for combination series-connected devices, the short-circuit-current rating
marked on the panelboard may be higher than the interrupting rating of
a specific circuit breaker installed or intended to be installed in the panelboard.
This higher rating is valid only if the specific overcurrent devices
identified in the marking are used within or ahead of the panelboard in
accordance with the marked instructions.
Panelboards to which units (circuit breakers, switches, etc.) may be added
in the field are marked with the name or trademark of the manufacturer
and the catalog number or equivalent of those units that are intended to be
installed in the field. Molded-case circuit breakers (see DIXF) may also be
Classified and marked as being suitable for use in certain panelboards in
place of or along with specific units marked on the panelboard.
Where in normal operation the load will continue for three hours or more,
molded-case circuit breakers and fused switches, other than fused power
circuit devices, should not be loaded to exceed 80% of their current rating
unless the device is otherwise marked. Low-voltage ac power switching
devices (see PAPU) and fused power circuit devices (see IYSR) used in panelboards
are suitable for continuous use at 100% of their rating.
Some panelboards may be provided with ground-fault protection for services
or major feeders. The circuit(s) so protected are identified by a marking,
such as on a wiring diagram.
These panelboards are intended for use with copper conductors unless
marked to indicate which terminals are suitable for use with aluminum conductors.
Such marking is independent of any marking on terminal connectors
and is on a wiring diagram or other readily visible location. If all terminals
are suitable for use with aluminum conductors as well as copper
conductors, the panelboard is marked ‘‘Use Copper or Aluminum Wire.’’ A
panelboard employing terminals or main or branch circuits units, individually
marked ‘‘CU-AL,’’ is marked as noted above or ‘‘Use Copper Wire
Only.’’ The latter statement indicates that wiring space or other factors make
the panelboard unsuitable for aluminum conductors.
Unless the panelboard is marked to indicate otherwise, the termination
provisions are based on the use of 60°C ampacities for wire sizes 14–1
AWG, and 75°C ampacities for wire sizes 1/0 AWG and larger as specified
in Table 310.16 of ANSI/NFPA 70, ‘‘National Electrical Code’’ (NEC). However,
3-wire, single-phase service entrance or feeder conductors for dwelling
units may be as covered in Section 310.15(B)(6) of the NEC. Termination
provisions are determined based on values provided in Table 310.16 or Section
310.15(B)(6), with no adjustment made for correction factors.
Some panelboards, constructed with interlocked main switching and overcurrent
protective devices, have been investigated for use in optional
standby systems in accordance with Article 702 of the NEC and are marked
‘‘Suitable for use in accordance with Article 702 of the National Electrical
Code ANSI/NFPA 70,’’ or, if provided within kit form, ‘‘Suitable for use in
accordance with Article 702 of the National Electrical Code ANSI/NFPA 70
when provided with interlock kit Cat No. ____.


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## Tom Solanto (Mar 11, 2011)

Mulder said:


> If that is the case, 408 wouldn't apply to loadcenters.


Mulder, that is exactly correct. Nice point!


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## Tom Solanto (Mar 11, 2011)

mcclary's electrical said:


> You're both wrong. Check the ul listing on those panels and youll see they are not panelboards. To say both are the same is completely false.


I did a search in the UL white book 2013. The words Load Center is not ever mentioned. If a load center is not a panel board then there must be a section for it in the White Book, correct?


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## Dennis Alwon (May 9, 2009)

mcclary's electrical said:


> You're both wrong. Check the ul listing on those panels and youll see they are not panelboards. To say both are the same is completely false.


The NEC does not use the term load center but the manufacturer does. IMO, they are virtually the same. The load centers are probably a cheaper model thats all.

I agree with Tom-- no mention of load center in the UL either


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## Dennis Alwon (May 9, 2009)

To the OP

Could the person you talked with be talking about 408.41



> 408.41 Grounded Conductor Terminations. Each grounded
> conductor shall terminate within the panelboard in an individual
> terminal that is not also used for another conductor.
> Exception: Grounded conductors of circuits with parallel
> ...


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## McClary’s Electrical (Feb 21, 2009)

Mulder said:


> If that is the case, 408 wouldn't apply to loadcenters.


It doesn't. Nec is a third party, and has many flaws. I'm going straight to the horses mouth. If the manufacturer's call one a panel board,  and one a loadcenter, I'm certainly not gonna be the goofball walking around calling them both the same thing. When you order a panel board, you get the guts, that's it. So keep playing lingo just because the nec doesn't define both, while I'm gonna keep referring to each by their (proper) manufacturers given name. 


Don't like it? Take it up with the people that make the panelboards, and load centers, and CLEARLY classify them differently.

http://www.schneider-electric.com/products/us/en/

Click on that link and you'll see them classified differently. 

Also, call up tomorrow and order a 200 amp panelboard and see what arrives.


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## Dennis Alwon (May 9, 2009)

mcclary's electrical said:


> It doesn't. Nec is a third party, and has many flaws. I'm going straight to the horses mouth. If the manufacturer's call one a panel board, and one a loadcenter, I'm certainly not gonna be the goofball walking around calling them both the same thing. When you order a panel board, you get the guts, that's it. So keep playing lingo just because the nec doesn't define both, while I'm gonna keep referring to each by their (proper) manufacturers given name.
> 
> 
> Don't like it? Take it up with the people that make the panelboards, and load centers, and CLEARLY classify them differently.
> ...



Jerry you are arguing nomenclature when we are saying as per the NEC they are the same ---


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## McClary’s Electrical (Feb 21, 2009)

Dennis Alwon said:


> To the OP
> 
> Could the person you talked with be talking about 408.41


Cmon. Stop choosing only the word you want. Both nec and ul clearly state panel board being assembled. They clearly state being installed in an enclosure. They clearly state the enclosure must match the panelboard. They clearly state the panelboard must be removable. 

So, 

Do you take a loadcenter and put it into an enclosure? 
Do you match the loadcenter to its enclosure? 


NOPE. 

You guys are just saying that because the nec lacks a definition. These are very clearly two different animals. 

Also. That part he highlighted doesn't mean it comes fully assembled. It very simply means the enclosure may come with the panelboard.


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## Dennis Alwon (May 9, 2009)

They are different animals but they are the same per the NEC rules.


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## McClary’s Electrical (Feb 21, 2009)

Dennis Alwon said:


> Jerry you are arguing nomenclature when we are saying as per the NEC they are the same ---


Actually I never stated what the nec defined. I only stated these are two different things. But hey, you guys are welcome to call them by the wrong name of you like. Let me know how it goes when you order your panelboard.


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## McClary’s Electrical (Feb 21, 2009)

Dennis Alwon said:


> They are different animals but they are the same per the NEC rules.


I actually think nec definition of panelboard doesn't meet at all how loadcenters are bought or installed.


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## Tom Solanto (Mar 11, 2011)

Dennis Alwon said:


> The NEC does not use the term load center but the manufacturer does. IMO, they are virtually the same. The load centers are probably a cheaper model thats all.
> 
> I agree with Tom-- no mention of load center in the UL either


I am with you. The UL section I pasted earlier says that the panelboard can come with the enclosure. Just like a load center. 

If I load center is not a panelboard where can we find the NEC regulations? It's the same.


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## cabletie (Feb 12, 2011)

Yes I believe they are all the same. I also believe that a eaton IPC or a Square D IPaC is also a panelboard mounted in a cabinet along with other panelboards and dry type transformers.


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## McClary’s Electrical (Feb 21, 2009)

As I stated before, it doesn't matter to me, feel free to walk around calling them the wrong name. Why would I care if you look silly?


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## Dennis Alwon (May 9, 2009)

mcclary's electrical said:


> As I stated before, it doesn't matter to me, feel free to walk around calling them the wrong name. Why would I care if you look silly?


It seems like you do care as you are making a point of it over and over. I don't think anyone looks silly over this issue. I hear the terms used all the time interchangeably. So what if it isn't exact. As I stated the NEC considers them the same in terms of requirements but you are correct the correct terms are not always being used.


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## McClary’s Electrical (Feb 21, 2009)

Dennis Alwon said:


> It seems like you do care as you are making a point of it over and over. I don't think anyone looks silly over this issue. I hear the terms used all the time interchangeably. So what if it isn't exact. As I stated the NEC considers them the same in terms of requirements but you are correct the correct terms are not always being used.


Maybe you're right. I would prefer on a forum of Profesional electricians that we don't use terms like 
Plug=receptacle
Ground=equipment grounding conductor
Ground=grounding electrode conductor
Ground= grounded conductor
110=120 volt
220= 240 volt
440 = 480 volt
Load center= panel board
Outlet= receptacle

All of the above are wrong. You're right, I would prefer we don't use them if we are to call ourselves professionals.


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## Tom Solanto (Mar 11, 2011)

mcclary's electrical said:


> Maybe you're right. I would prefer on a forum of Profesional electricians that we don't use terms like
> Plug=receptacle
> Ground=equipment grounding conductor
> Ground=grounding electrode conductor
> ...


Great point! Agree 100%. If we want to increase, develop or maintain our credibility we need to speak like pro's. It's really important not to sound like a lay person.


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## McClary’s Electrical (Feb 21, 2009)

Tom Solanto said:


> Great point! Agree 100%. If we want to increase, develop or maintain our credibility we need to speak like pro's. It's really important not to sound like a lay person.


Thats really all I ever meant. I wasn't arguing what was defined, just that these two terms did not mean the same thing.


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## Hawkrod (Mar 19, 2012)

Yeah, I agree as well, what things are called and what they are is not always the same thing. To me a load center is a panelboard but I know others do not agree. Sometimes people post here using local names and it leaves me scratching my head trying to figure out what they are saying. It does not make either of us wrong.


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## dielectricunion (Nov 29, 2012)

So, panelboards vs load centers aside... Where do I find the rules applying to a residential load center in the NEC?

Is 408 the wrong article to be looking through ?


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## cabletie (Feb 12, 2011)

Under panelboards


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## Carultch (May 14, 2013)

mcclary's electrical said:


> You're both wrong. Check the ul listing on those panels and youll see they are not panelboards. To say both are the same is completely false.


What is a general term for Load Center, Panelboard, Switchboard, and Switchgear, that I can use in all applications and still be correct?

"Circuit Distribution Enclosure", perhaps?

As I understand it, these all accomplish the same purpose, just at different ampere/size categories.

Heck, even Motor Control Center is similar enough to this kind of equipment, that I'd call it a Switchboard by mistake.


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## five.five-six (Apr 9, 2013)

mcclary's electrical said:


> As I stated before, it doesn't matter to me, feel free to walk around calling them the wrong name. Why would I care if you look silly?


Irony...


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## Barjack (Mar 28, 2010)

This is from Schneider's FAQ:





> What is the difference between Load Centers and Panelboards?
> Issue:
> What is the difference between QO Load Center and NQ Panelboards?
> Product Line:
> ...


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## McClary’s Electrical (Feb 21, 2009)

Barjack said:


> This is from Schneider's FAQ:


So what. Cutler hammer makes a ch panel that is classified as a panelboard also. That doesn't prove anything


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## macmikeman (Jan 23, 2007)

Somewhere I can sense Bob Dylan sitting back on his easy chair in front of a computer connected to the internet laughing at all this.....


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## Barjack (Mar 28, 2010)

mcclary's electrical said:


> So what. Cutler hammer makes a ch panel that is classified as a panelboard also. That doesn't prove anything



You know what you are? Really awesome, that's what. 


Sent from my iPhone using electriciantalk.com


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## Carultch (May 14, 2013)

mcclary's electrical said:


> So what. Cutler hammer makes a ch panel that is classified as a panelboard also. That doesn't prove anything


It proves that you are being nitpicky about a distinction that isn't relevant to the original question. The point is, that it is a manufactured enclosed assembly that contains a set of busbars, a breaker for each circuit, an insulated neutral bar, and an enclosure bonded ground bar.

This question was about whether it is or isn't a violation to connect neutrals to the ground bar, in an enclosure of this type.


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## McClary’s Electrical (Feb 21, 2009)

Carultch said:


> It proves that you are being nitpicky about a distinction that isn't relevant to the original question. The point is, that it is a manufactured enclosed assembly that contains a set of busbars, a breaker for each circuit, an insulated neutral bar, and an enclosure bonded ground bar.
> 
> This question was about whether it is or isn't a violation to connect neutrals to the ground bar, in an enclosure of this type.


So when you wire a house, you enter all the odd circuits on the left side of the panel, and all the even circuits on the right side of the panel? Without criss crossing any? Because that's a requirement for a panel board.


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## cabletie (Feb 12, 2011)

That is a requirement of a switchboard. The basic requirement is that they don't want feeders in one section going through other sections. Typically these sections are 30" wide and bolted together. The buss between sections are also bolted together in the field. One 30" section is a vertical section.


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## Carultch (May 14, 2013)

mcclary's electrical said:


> So when you wire a house, you enter all the odd circuits on the left side of the panel, and all the even circuits on the right side of the panel? Without criss crossing any? Because that's a requirement for a panel board.


I'd just go back to 110.12:
110.12 Mechanical Execution of Work.
Electrical equipment shall be installed in a neat and workmanlike manner.

In order to meet this, you'd need to keep good organization of your wiring inside the enclosure, and minimize crossing as much as practical.

I'm aware that the requirements become more strict as your equipment grows in size. Should I build a load center to the panelboard's rules, it would still be correct.


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## wistech (May 14, 2015)

Wow, this thread got out of hand! Has anyone actually answered the poster's question?

The answer is: neutrals and grounds can share the same termination bar if that termination bar is bonded to ground, which is usually done at the main panel... errr load center. However, sometimes that main breaker is located in the meter socket outside, even if there's a main breaker in the main p... load center. If that's the case, there will be a separate ground bar for the grounds and the neutral to case bond is done in the meter socket enclosure.

Hope that helps


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## don_resqcapt19 (Jul 18, 2010)

mcclary's electrical said:


> As I stated before, it doesn't matter to me, feel free to walk around calling them the wrong name. Why would I care if you look silly?


This just points out the difference between "field language" and "code language". There are many things where different terms are used in the field and in the code. For the application of the code, you have to use the "code language". 

Where do I find the rules for installing a load center in the NEC?


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## reddog552 (Oct 11, 2007)

*Bob Dillon*



macmikeman said:


> Somewhere I can sense Bob Dylan sitting back on his easy chair in front of a computer connected to the internet laughing at all this.....


My name is Bob Dillon


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## B-Nabs (Jun 4, 2014)

mcclary's electrical said:


> I'm going straight to the horses mouth. If the manufacturer's call one a panel board, and one a loadcenter, I'm certainly not gonna be the goofball walking around calling them both the same thing.





Barjack said:


> This is from Schneider's FAQ: A QO Loadcenter is a panelboard.





mcclary's electrical said:


> So what. Cutler hammer makes a ch panel that is classified as a panelboard also. That doesn't prove anything


Seems to me the horse's mouth is saying a loadcenter is a panelboard and you are contradicting yourself McClary.

This is a case of categories, where one category is a member of another category, but not the other way around. That is to say, a loadcenter is a type of panelboard, but a panelboard is not necessarily a loadcenter. Just like if I said water is a liquid, but a liquid is not necessarily water.


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## FaultCurrent (May 13, 2014)

A cabinet or a cutout box is just the enclosure.

A cutout box is surface mounted.

A cabinet can be surface or flush mounted.

A panelboard, or a load center if it pleases you, can be installed in a cabinet, cutout box, switchboard, or whatever.


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## wistech (May 14, 2015)

Please moderator, for the love of God close this thread! ;-P


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## telsa (May 22, 2015)

*The NEMA players are trying to shift...*

We've all seen the ancient panels when C/Bs were new (ish) and wire space for the conductors was pitiful.

Sixty-year old panels even featured bronze neutral-grounding busses with 'soft' bronze/ brass flat headed button-top screws. Yiikes.

Today the NEMA players have pulled the 42 circuit limit on lighting panel boards -- pretty much eliminating even the term 'lighting' -- to accommodate the slew of AFCI and GFCI C/Bs their code crews have convinced the NEC to adopt as mandatory.

BECAUSE of the tricky characteristics of AFCI circuit build outs, we're seeing the NEMA players massively increase the length and adjacency of the neutral return bars.

(Sq D is bringing out a scheme that has trick breakers and a trick neutral that mates up very much like a hot bus bar. C-H has full length neutrals that are hard on the sides of both breaker rows -- for AFCI / GFCI neutral pigtail connections.)

CONSEQUENT to that design, the NEMA players are slapping in ADDITIONAL grounding conductor rails -- even for -- ESPECIALLY for -- residential Services.

We should look to see a shift over to having ALL neutrals landed on the neutral bars -- only ; ALL grounding conductors (green/bare) landed on separate rails with explicit bonding jumpers -- probably anodized green or white -- EVEN AT single point residential services... with allowance for jumpers to run of to the meter pan where customary. 

All of the prior art will be grandfathered, of course.

&&&&

ONE aspect of having the greens and whites separate even in a residential panel is that it opens up the possibility of a quick test of the MAIN circuit breaker.

The latest generation of solid state testers is the size of a Chicklets tablet. One can imagine a time, SOON, when it will be customary to pull the jumpers (neutral to GEC bond) and let the magic tester profile the MAIN C/B.

This would likely also be a time when the NEUTRAL RETURN back to the Poco could be digitally tested -- very much in the style of ground rod impedance testing performed at this time.

I think this is where the NEMA players are headed -- and will take the NEC writers with them.

It will mean that weird, crazy, marginal neutral returns -- from the Service back up to the Poco will become cheap and easy to spot. (for the first time, it would seem)

It would also permit the quality of the GEC to be drastically easier to test.

Right now, with all of these conductors (grounded and grounding) under the same 'rail' no speedy test is possible/ practical... Making it impossible to market any (digital logic) test gear to resolve decaying residential Services.

Sick neutrals -- especially neutral returns to the Poco -- are the bane of our craft.

Opinions, please:


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## B-Nabs (Jun 4, 2014)

Jesus Murphy man, you missed your calling as a novelist.


Sent from my iPhone using Tapatalk


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## wistech (May 14, 2015)

telsa said:


> We've all seen the ancient panels when C/Bs were new (ish) and wire space for the conductors was pitiful.
> 
> Sixty-year old panels even featured bronze neutral-grounding busses with 'soft' bronze/ brass flat headed button-top screws. Yiikes.
> 
> ...


I've already come across a QO panel with a neutral bus bar for AFCIs and GFCIs. The neutral connection to the AFCI is made through the metal clip that typically attached to a plastic rod in regular QO panels. Pretty neat idea.


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