Sub feed panel location

[elvis0]

I have a 2 section panelboard. Each section is 20"wide. Can one section be mounted above the other with all branch circuits for both sections entering the top section.
I am unclear as to whether NEC 403.8(A)3 applies to panelboards and switchboards or switchboards only.

 

[infinity]

Yes, this is permitted. You'll still need your 30" of width for the working space in front of the panels.

 

[augie47]

switches

switches

not sure of the size of your panelboards but don't forget 404.8

 

[thecrazyezel]

I have heard about this configuration before. I do not believe it is legal because you are using the top panel as a raceway for the bottom panel and you are not allowed to use panels as a raceway. There might also be height requirements that might have to be met as well. I could not find the section that mentions this but maybe someone else knows if this is possible or not. I would steer away from it if possible though...another idea would be to call the AHJ and see if they will even allow it or not. It might be legal, but they might not allow it in their county/city. Chances are this isn't the first time they have run across a situation like this.

 

[George Stolz]

I have heard about this configuration before. I do not believe it is legal because you are using the top panel as a raceway for the bottom panel and you are not allowed to use panels as a raceway.

Code reference, please?

 

[infinity]

Crazy, why would this be illegal?

 

[hbendillo]

Is there a limitation to wire fill in a panelboard gutter? Do you have space problems mounting the panelboards side-to-side? How high would the top most circuit breaker be? You could do something creative with a wireway to run branch circuits to the bottom panel if you have room instead of through the top panel. Look at Articles 312.7 and 312.10. You may be violating something there.

 

[badcowboy]

Code

Code

In the 2002 code, the 408.3A section says that it applies to "Switchboard or Panel board".

As far as running conductors through one panel board for another, it is not allowed (2002 NEC 408.3(A)(3)). You may run wire horizontally if separated by a barrier, but not vertically unless that wire is intended for termination in that vertical section.

 

[thecrazyezel]

Please see this webpage

http://www.codebookcity.com/codearticles/nec/necarticle408.htm

Item 1 - To respect the modular integrity of the panelboard and not to use it as a raceway.

I agree with 408.3(A)(3).

In addition there could be an accident where someone would throw the main circuit breaker and think all of the conductors were off and then touch a hot one.

Also, you have to mind 404.8(A). You can argue one way or another but there are just to many catches for this one. 408.3(A)(3) is clear and if you choose to do the installation you could get called out on it by the AHJ.

 

[LarryFine]

In my opinion, 408.3(A)(3) does not apply to two stacked panel sections, as they effectively become a single section, vertically speaking. 408 is about busbars and conductors, not the enclosures themselves. The reference to barriers in the exception to (A)(3) bears this out.

 

[iwire]

Larry if it's 'one section' then there are two many overcurrent devices.

I think we are better off calling it two sections.

But 408.3(A)(3) only applies to switchboards notice the "as applicable" in 408.3(A).

That said....it does not matter.

You can use panel boards as raceways as long as you do not exceed the fill.

This is not 'up to the inspector' it is the NEC.

Take a look at 312.8 and be sure to read past the first sentence.

 

[iwire]

Please see this webpage

http://www.codebookcity.com/codearticles/nec/necarticle408.htm

Item 1 - To respect the modular integrity of the panelboard and not to use it as a raceway.

I agree with 408.3(A)(3).

So do I, but that specific section only applies to sections of a switchboard.

A panel board does not have 'vertical sections"

if you choose to do the installation you could get called out on it by the AHJ.

I don't think so, I would point the AHJ to 312.8.

 

[infinity]

So do I, but that specific section only applies to sections of a switchboard.

A panel board does not have 'vertical sections"

I don't think so, I would point the AHJ to 312.8.

Agreed, the requirements for switchboards and panelboards are not the same. 312.8 directly applies to panelboards.

 

[wbalsam1]

.....As far as running conductors through one panel board for another, it is not allowed (2002 NEC 408.3(A)(3)). You may run wire horizontally if separated by a barrier, but not vertically unless that wire is intended for termination in that vertical section.

You've said panelboard in your quote above, but the provision you quoted (3) is referring only to conductors in or travelling horizontally through vertical sections of switchboard...