Why not switchboards?

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RB1

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Where in the code does it require a switchboard used for service equipment to have a rating not less than the load calculated in accordance with Article 220? I have found plenty of references to individual disconnects, but nothing on the bus itself.
 
iwire said:
IMO the busses in that case are service conductors and 230.42 would apply.
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I am not sure I can agree with that. Don?t you go through an overcurrent device, or at least a disconnecting means, before you hit the buswork? Isn?t that the point of demarcation between the ?service conductors? and ?feeders??

It?s a pity that 408, Part II, does not open with the same opening sentence as does 408, Part III. We may have only 110.3(B) to fall back upon.
 
ryan_618 said:
I don't have my 2008 code here at work, but I was thinking that they clarified this in the 2008. I could be mistaken though.
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I see some clarification for panelboards, but not for switchboards.
 
charlie b said:
I am not sure I can agree with that. Don’t you go through an overcurrent device, or at least a disconnecting means, before you hit the buswork?
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I certainly could be mistaken but my take on the question was a section of switch board without a single main but six or less service disconnects installed in it. :)

That is a fairly common way to avoid GFP requirements.
 
This is the section I was thinking:
230.79 Rating of Service Disconnecting Means.
The service disconnecting means shall have a rating not less than the calculated load to be carried, determined in accordance with Part III, IV, or V of Article 220, as applicable. In no case shall the rating be lower than specified in 230.79(A), (B), (C), or (D).
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I think it can be argued rather easily that the disconnecting means includes the entire assembly, not just the breaker(s).
 
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