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Retrofitting and UL Listings: What You Need to Know

Retrofitting existing electrical equipment, including reconditioning components, can be a cost-effective way to improve your equipment’s reliability and safety without replacing it. The retrofit process involves assessing equipment, such as switchgear or circuit breakers, and identifying which components are outdated and should be upgraded. This process reduces risk to employees and machinery. It also minimizes the period of equipment downtime caused by a complete replacement or the extensive downtime caused by electrical equipment failure.


However, when retrofitting or refurbishing existing equipment, it’s also important to consider how that will affect its compliance. For various electrical equipment in industrial, agricultural, civil, defense, and other environments, the relevant regulations will be the National Electrical Code/NEC (NFPA 70) and a specific UL listing for that equipment and its use. Reconditioned, refurbished, or retrofitted equipment that was compliant when it left the factory can lose this rating once it has been altered, so it’s important to know how that process works, which equipment is affected, and how to ensure ongoing compliance.


AI artwork of men working on retrofitting a switchgear

UL Listings and Reconditioning


Reconditioning, refurbishing, rebuilding, retrofitting, and rebuilding all refer to roughly the same process: updating existing equipment with newer components and thus restoring it to at least original operating conditions. However, there is a difference between this process and normal servicing of equipment that never leaves the facility or one-to-one replacement of parts. For example, replacing a motor starter, fuse, or circuit breaker does not count as reconditioning and doesn’t affect the equipment’s UL compliance.


Reconditioned or retrofitted equipment can be certified as UL compliant through its original manufacturer or a UL Solutions authorized vendor with the requisite manufacturing skills, capacity, facilities, and technical knowledge to restore products to the applicable UL standard. Being part of UL Solutions’ rebuilt equipment program requires the vendor to use appropriate materials according to the specific UL listings, have appropriate measurement and testing equipment at their facility, and know which equipment can be reconditioned.


Reconditioned equipment must have its original compliance listing mark removed and have a new one added with the words ‘Reconditioned,’ ‘Rebuilt,’ ‘Refurbished’, or ‘Rebuilt.’ Some changes, however, such as changing a luminaire for an LED light, don’t require recertification.


Applicable and Non-Applicable Equipment for Retrofitting


Retrofitting existing equipment is a cost-friendly solution that improves safety, reduces risk, and increases equipment lifespan. Due to specific design features or their role in protecting the safety of people in the vicinity, some equipment can’t be reconditioned and re-assessed.

The types of equipment that can be reconditioned include:


  • Electrical switchgear and switchboards or individual sections of them

  • Electromechanical protective relays 

  • Current transformers

  • Low and medium-voltage circuit breakers

  • High-voltage circuit breakers


As mentioned, certain types of equipment can’t be reconditioned or refurbished and regain compliance, which are generally quite specific in their assembly and function, including:


  • Fire pump controllers

  • Molded-case circuit breakers

  • Low-voltage circuit breaker trip units

  • Arc-fault circuit interrupters

  • Ground-fault circuit interrupters

  • Low-voltage lighting systems

  • Branch-circuit ground fault protection

  • Receptacles

  • Flanged surface devices

  • Low and medium-voltage fuse holders

  • Non-renewable fuses for low and medium-voltage

Certification for Retrofitted Equipment


The NEC (Section 110.21(A)(2)) is clear that reconditioned equipment can’t be certified as compliant based solely on its original listing. To maintain compliance with relevant UL listings for electrical equipment and its specific usage, the refurbishment must be performed by a certified vendor. It is possible for retrofitted equipment that has been otherwise refurbished to be field tested and achieve compliance, but that requires a site visit from an inspection team.


When completing a retrofit and returning the equipment to operations, the NEC (Section 110.21(A)(2)) states the equipment must be marked with the name or other identifying marking of the vendor who has performed the renovation, along with the date of the retrofit. The standards to be applied to retrofitted equipment would apply to newly manufactured equipment rather than those applicable at the original manufacture date. 


Though reconditioning means that the original certification listing mark is removed and replaced by its new certification mark, this doesn’t mean removing the entire label as that contains information such as voltage and short circuit current ratings, along with other information that’s potentially critical for the re-installation of the retrofitted equipment.


AI artwork of men working on retrofitting switchgear

Retrofit with Enercon


Retrofitting allows companies to improve safety for personnel and machinery and reduce risk and equipment downtime at a reduced cost compared to total equipment replacement. However, those undergoing a retrofitting process must be aware of how this will affect their NEC and UL compliance. The most important factor is ensuring that a UL-certified vendor is doing the retrofit. It’s also important to consider the components and equipment that can’t be refurbished and maintain compliance due to their design or safety importance.


At Enercon, we help organizations of all sizes meet compliance requirements through new builds and retrofits. With our large UL508A / UL698A panel shop, we can handle any job specifications and help you retrofit your electrical equipment. To find out more, contact us here.

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