Question
Is a UL Solutions sign section label required on each section/housing of a LED Class 2 powered multi section/housing sign? I understand there recently was a change to UL 48, the Standard for Electric Signs, that relaxed Certification/Listing Mark requirements for these types of signs. Why the change in labeling and what should I look for?
Answer
A UL Sign Section Certification (Listing) Mark is not required on sign housings that are supplied by Class 2 power only. Instead, such a multi-housing sign can now carry a single Sign Certification (Listing) Mark. Only sign sections that house branch circuit power have to be designated and labeled with the UL Electric Sign Section Certification (Listing) Mark.
Traditionally, signs consisting of multiple interconnected parts (such as channel letters used to spell a facility name) have had branch circuit power brought into each section. Each section required evaluation and safeguards against fire and electric shock risks. Each section was then individually labeled as a Certified (Listed) Sign Section to demonstrate compliance with the safety requirements of UL 48, Standard for Electric Signs.
The shift to light-emitting diode (LED) technology has had tremendous impact on the sign community. The energy efficiency improvements allow LED signs of reasonably large scale to operate within Class 2 power limits, which reduces the level of safeguards needed to manage fire and electric shock risks.
One of the secondary benefits of operating within Class 2 limits is the ability to utilize the Class 2 wiring methods defined in the National Electrical Code® (NFPA-70® 2023; NEC®) between remotely located sign housings. This allows a sign to be spread over a large area with many small, individually illuminated parts.
What’s changed?
In December 2023, UL 48 was revised to more appropriately address the safety risk profile of multi-housing signs operating within Class 2 power and voltage limits.
These revisions redefined “section signs” as “A sign shipped as subassemblies that require other than class 2 field-wiring between the subassemblies to complete the overall sign.”. The revised definition specifically excludes housings that contain only Class 2 circuits. The revisions also require the installation instructions to identify all of the housings that are suitable for field installation with the sign using Class 2 wiring methods. This ensures that the Class 2 power supply is operated within its marked rating.
The UL Solutions sign certification program retains its separate labeling provisions for individual vs section signs. Each section of a section sign is still required to be identified, e.g.,“1 of 4”, “2 of 4”, etc.. However, these newly redefined multi-housing signs only require a single Electric Sign (not Electric Sign Section) label, with the single label typically applied to the housing containing branch circuit power (where the Class 2 power supply is located). This new approach reduces the number of certification labels and provides sign manufacturers more options to manage sign aesthetics especially for signs with many (often small) separate housings.
UL Solutions continues to maintain the section sign certification program to address designs that bring branch circuit power into each section. Manufacturers can choose to certify any multi-housing sign as a section sign if that’s their preference.
For more information on how these signs may be labeled, see the guide information for the product category Electric Signs (UXYT) on UL Product iQ at www.UL.com/piq; enter UXYT at the search field.
