What is UL 1077 ?

Title: What is UL 1077 and UL 1137? A Comprehensive Guide to Supplementary Protectors

Electrical equipment is an essential part of our daily lives, and it is crucial to ensure its safety and reliability. Supplementary protectors, such as fuses, circuit breakers, and surge protectors, are installed in many electrical systems to protect sensitive equipment and wiring from damage caused by excessive current or fault conditions. However, these devices may not always perform as expected, which is where UL comes in. UL 1077 and UL 1137 are two widely recognized standards for supplementary protectors that provide guidelines and regulations regarding their performance, construction, and testing. In this article, we will explore what UL 1077 and UL 1137 are all about and how they impact various industries.

UL 1077: The Purpose of the Standard

UL 1077 is a technical standard established by Underwriters Laboratories (UL) to ensure the safety and reliability of supplementary protectors used in electrical systems. The standard provides guidelines and regulations regarding the performance, construction, and testing of these devices. It aims to ensure that supplementary protectors can interrupt current, withstand electrical and mechanical stresses, and provide reliable protection under specified operating conditions.

UL 1077 covers both thermal-magnetic and magnetic trip variants and establishes minimum requirements for their marking and documentation. The standard provides a comprehensive approach to evaluating the performance of supplementary protectors and ensuring their compliance with safety standards.

UL 1137: The Role of the Standard

UL 1137 is a technical standard developed by UL to provide guidelines for the construction, installation, and maintenance of electrical equipment used in hazardous locations. These locations include areas where flammable gases, vapors, liquids, or combustible dust particles may be present. The standard aims to prevent fires, explosions, and other accidents caused by the ignition of these hazardous substances due to electrical equipment.

UL 1137 covers various aspects of electrical safety, including the design and testing of equipment, selection of suitable materials, proper wiring, grounding techniques, and the use of protective measures such as enclosures and seals. Compliance with UL 1137 ensures that electrical equipment can be safely operated in potentially dangerous environments.

Conclusion:

UL 1077 and UL 1137 are important standards for supplementary protectors used in electrical systems. They provide guidelines and regulations for the performance, construction, and testing of these devices and ensure that supplementary protectors can interrupt current, withstand electrical and mechanical stresses, and provide reliable protection under specified operating conditions. Compliance with these standards is essential for the safety and reliability of electrical systems.