UL’s Name Change and Circuit Breakers for Back Feeding

UL Solutions Question Corner
UL Solutions Question Corner

Question

I see UL has now changed its name to UL Solutions, and the UL Question Corner is now the UL Solutions Question Corner.  Has anything else other than the name changed?  Are UL Certification (Listing) Marks changing?  I am on a UL Standards Technical Panel (STP), is that process changing?

Answer

On June 27, the UL enterprise revealed new brands for its three organizations — UL Research Institutes, UL Standards & Engagement, and UL Solutions. The brands reflect and clarify the unique role that each organization plays in working for a safer world.

The UL Research Institutes’ brand signals its focus on rigorous independent research into ongoing and emerging human safety risks. As threats evolve and their consequences become more severe, UL Research Institutes pursues scientific discovery to advance public safety — marshaling resources to scan for and assess emerging human safety risks in areas such as autonomous systems and artificial intelligence.

The UL Standards & Engagement brand exemplifies its longstanding role as a critical facilitator of standards-related public-private partnerships around the world. UL Standards & Engagement translates data and safety science research into actionable, rigorous safety standards and drives safety advocacy campaigns focused on improving public safety.

The UL Solutions brand represents its commitment to partnering with customers and stakeholders around the world to help solve safety, security, and sustainability challenges. A global safety science leader, UL Solutions delivers testing, inspection, and certification services, together with software products and advisory offerings, that support our customers’ product innovation and business growth.

While the logos for the organizations have been updated to reflect the new brands, the existing UL Certification Marks, the UL Solutions Certification (Listing) process, and the UL Solutions staff and technical expertise remain unchanged. The Standards Technical Panel (STP) process used by UL Standards & Engagement to develop UL Standards is also not changing.

Learn more about UL Solutions and our new brand at https://www.ul.com/ulsolutions.

 

Question

Are UL Certified (Listed) Circuit breakers marked “line” and “load” considered suitable for back feed or reverse current?  If they are marked line and load, is there an additional rating that could identify the circuit breaker as suitable for back feed or reverse current as referenced in 2020 NEC® 705.12(D)?

Answer

UL Certified (Listed) molded case circuit breakers marked “line” and “load’ identify the direction of the current flow and are not investigated for reverse current or back feeding. There is no additional rating for circuit breakers marked “line” and “load” that will identify a circuit breaker as suitable for back feed or reverse current.

Only circuit breakers NOT marked “line” and “load” are also investigated for reverse current or back feeding.

Molded case circuit breakers are investigated for compliance with UL 489, the Standard for Safety for Molded-Case Circuit Breakers, Molded-Case Switches, and Circuit-Breaker Enclosures, and are Certified (Listed) under the product category Circuit Breakers, Molded Case and Circuit-breaker Enclosures (DIVQ). The product marking section of category DIVQ notes that circuit breakers are marked “Line/Load” unless acceptable for use with the connections reversed. Only circuit breakers not marked line and load are investigated for reverse current to be used for back feeding a circuit breaker.

The UL guide information and Certifications (Listings) for DIVQ can be located on UL Product iQ™ at www.ul.com/piq; enter DIVQ at the search field.

The complimentary Molded Case Circuit Breakers Marking and Application Guide located at www.ul.com/markingguides explains circuit breaker markings in detail.

 

Note: We are now UL Solutions. Learn more about our new brand at https://www.ul.com/ulsolutions.

About UL Solutions
UL Solutions helps create a better world by applying science to solve safety, security and sustainability challenges. We empower trust by enabling the safe adoption of innovative new products and technologies. Everyone at UL shares a passion to make the world a safer place. All of our work, from independent research and standards development, to testing and certification, to providing analytical and digital solutions, helps improve global well-being. Businesses, industries, governments, regulatory authorities and the public put their trust in us so they can make smarter decisions. To learn more, visit UL.com.