What is UL 997?

UL 997 is a widely recognized standard that provides guidelines for the safety of industrial control panels in the United States. It sets forth requirements for the construction, performance, and testing of these panels to ensure their safe operation in various industrial environments.

Construction Requirements

The construction requirements specified by UL 997 cover the design and assembly of industrial control panels. These requirements address issues such as proper enclosure and component spacing, wiring methods and connections, protection against electrical hazards, and labeling. Compliance with these construction requirements ensures that the control panel is built to withstand the rigors of the intended industrial environment and minimizes the risk of electrical accidents.

Performance Requirements

In addition to construction requirements, UL 997 also sets performance requirements for industrial control panels. These requirements cover factors such as temperature rise, short circuit current ratings, and overload and fault protection. Panels must be tested to demonstrate compliance with these requirements, ensuring that they can safely handle the electrical loads they are designed for and provide reliable performance over time.

Testing and Certification

UL 997 requires that industrial control panels undergo rigorous testing by a certified laboratory. The testing process includes various assessments such as dielectric voltage-withstand, ground continuity, and protection against electric shock. Once a control panel successfully meets all the requirements, it receives UL listing or certification, indicating its compliance with UL 997 standards. This UL certification instills confidence in end-users, confirming that the control panel is safe, reliable, and suitable for use in industrial applications.