What are the differences between the extended end gutter feature, the wireway feature, and the equipment space feature in an NQ or NF panelboard?
UL 67, UL 50, CSA C22.2 No.'s 20-M1989 & 94-M91, NEMA PB1, NFPA 70 Art. 408, Federal Specification W-P-115C Type 1 Class 1 , 2003 IBC, NFPA 5000, ASCE/SE17
Understanding the difference in these optional features is essential to their correct application.
Equipment space provides additional space in the panelboard box, a barrier from the rest of the panelboard, and a separate cover with door for the extra space. Also equipment space can only be provided at the load end (as opposed to incoming line end) of the panelboard. Equipment space may be provided for NEMA 1, NEMA 3R and NEMA 4/4X stainless steel enclosures. This feature is available factory assembled only.
An extended end gutter provides additional space in the panelboard box and is selectable for either top or bottom location, independent of the direction of feed (top or bottom) to the panelboard. With an extended end gutter the sheet metal for the box is extended and is a continuous piece, not an addition bolted onto the standard box. Similarly, the cover for an extended end gutter is one continous piece of metal. No barrier is provided with an extended end gutter.
Extended left and/or right side gutters are also available, and similar to extended end gutters, the box and cover sheet metal are extended, not pieced onto the standard box and cover.
Extended gutters for NQ and NF panelboards are available for NEMA 1 enclosures only and are available factory assembled only.
Lastly, a wireway feature is a separate piece which is bolted onto the standard box, and it may be added to either the top or bottom of the box, independent of the direction of feed (top or bottom) of the panelboard. When installing the wireway, first the box end wall is removed, the wireway is added and the end wall is reinstalled onto the end of the box, which now has been extended by the wireway. The wireway cover is a separate piece from the standard cover. No barrier is furnished with a wireway. Wireways are available for NEMA 1 enclosures only. They are available as a factory assembled option, or they may be purchased separately for field installation.