NEC 2008, Article 408.36, OCPD's in panelboards

[AQC]

Could somebody help me understand NEC 2008, Article 408.36. This involves OCPD's in panelboards. Also, what are your experiences with this topic in regards to installation of panelboards greater then 42-poles?

 

[roger]

For your first question, it simply means that if the panelboard is rated for 200 amps it must be protected at not more than 200 amps.

I am not sure I understand your second question but if it has to do with Exception No. 2, it would mean you could not use a panelboard with more than 42 breakers for this application.

Roger

 

[Dennis Alwon]

Many areas have not even seen panelboards that have more than 42 circuits. I understand that Sq.D makes a 60 cir. panel but I know there are none of those options available around my area. I dn't think GE even makes one yet. I prefer sub panels to one large panel.

 

[AQC]

My 2nd question was not intended to be related to the 1st question. For clarification, I simply wanted to know if anybody has installed panelboards greater than 42-poles, and what where your experiences with them, good or bad?? The NEC 2008 eliminated the 42-pole limit (except in the exception cases).

 

[kwired]

I will be installing a 66 circuit Square D NF 277/480 panelboard soon. Have not seen it yet but the enclosure is 86" high. Will need to watch out to make sure highest breakers are not too high. Not too concerned about having more than 42 poles because the nature of the connected loads will not have anymore circuits loaded at same time than I would be able to put into a 42 circuit panel. I will be using 54 poles in my installation.

 

[Leestarkweather]

I will be installing a 66 circuit Square D NF 277/480 panelboard soon. Have not seen it yet but the enclosure is 86" high. Will need to watch out to make sure highest breakers are not too high. Not too concerned about having more than 42 poles because the nature of the connected loads will not have anymore circuits loaded at same time than I would be able to put into a 42 circuit panel. I will be using 54 poles in my installation.

I have done 84 circuit NQ panels with 3P 400A MCB at top and 400A Thru Feed Lugs at bottom--panel is very tall, but by mounting no more than 4" off the floor (to allow sweep broom), center of handle of MCB in ON position was compliant. There are large gutters at both ends, which brings the CB's down in height.