Code HunterRead the article: CODE HUNTER — Calculations, 2014 NEC
I have seen many display cases and commercial displays in retail stores made by millwork shops that incorporate lights and outlets, concealed power strips and power supplies, have multiple large flat screen displays, and a mixed bag of LED tape lights and drivers that are not Listed. Does UL list these types of display products as entire assemblies?
Yes. UL Certifies/Lists a broad range of these types of products under two different product categories. From traditional display cases showcasing luxury goods to standalone kiosks used for product demonstrations, checking prices or printing coupons, modern retail displays pose a number of potential risks to both retail workers and consumers. Many displays incorporate lighting, integrate computers, or include other electrical or electronic features that are potential sources of fire or electrical shock. It is important to understand that listed or recognized components such as luminaires may not be rated for in cabinet use. The displays must be designed so that they don’t unexpectedly collapse under the weight of heavy products such as televisions and computers, and can be quite challenging for an electrical inspector to inspect. The UL Certification/Listing of these displays address these concerns.
UL Certifies/Lists display showcases under the product category Wired Cabinets (ZNXR) covering products such as illuminated and non-illuminated jewelry cabinets, and cosmetic showcases. UL also Certifies/Lists commercial displays under the product category Commercial Displays (IYMX) covering products such as lighted and powered shelving units, standalone kiosks, luminary store displays, motorized rotating merchandise displays, and motorized carpet flooring displays. A commercial display is a furnishing other than a showcase or cabinet that is used in a commercial establishment to display merchandise.
Wired cabinets (category ZNXR) are evaluated for compliance with UL 65, the Standard for Safety for Wired Cabinets, and can be permanently connected or cord-and-plug connected. Cord-and-plug connected wired cabinets are limited to groups of six or less coupled together by flexible cord and locking connectors. One of the wired-cabinet sections is connected to a permanently installed receptacle in the building structure by a flexible cord and plug cap rated 15 or 20 A. The electrical requirements are based on those in NEC 410.59.
Permanently wired cabinets may include convenience outlets for connecting point of sale equipment and similar products. Cord-and-plug connected wired cabinets can have receptacles for connecting factory-installed equipment, such as luminaires. These receptacles are not intended for powering additional equipment.
Wired cabinets may be divided into sections when it is impractical to ship as a single unit. When multiple sections of a Wired Cabinet are sent to the installation site, each major subassembly bears a “Wired Cabinet – Section ___ of ___” Certification/Listing Mark, (the first blank identifies the number of the section, and the second blank identifies the total number of sections that constitute the complete wired cabinet). Each group of wired-cabinet sections includes installation instructions describing or illustrating proper assembly and electrical connection of the sections when applicable.
In contrast, commercial displays (category IYMX) are evaluated for compliance with UL 962, the Standard for Safety for Household and Commercial Furnishings, and can be permanently connected or may be cord-and-plug connected with up to two power-supply cords.
For commercial units with a surface area greater than 10 sq. ft. and intended to be adjacent to other furnishings, or standalone units that are greater than 20 sq. ft., the surface-burning characteristics of the materials used in these assemblies may be no greater than that of ordinary lumber used in on-site construction. Materials used for finished surfaces must have a flame-spread rating of 200 or less and, unless otherwise marked, a smoke-developed rating of 450 or less. These displays will be marked with the UL Certification or Listing Mark identifying them as a Commercial Display.
The UL Guide Information and Certifications/Listings can be viewed for both of these categories in the 2015-16 UL White Book PDF at www.ul.com/whitebook. Wired Cabinets (ZNXR) can be found on page 624 and Commercial Displays (IYMX) on page 253. This information is also available on UL Product Spec at www.ul.com/productspec; please enter ZNXR or IYMX at the category code search.