What is UL 98?

UL 98, also known as Underwriters Laboratories Standard 98, is a safety standard for disconnecting switches used in electrical systems. It sets forth requirements and test procedures to assess the performance of these switches to ensure their safe operation.

Importance of UL 98

UL 98 plays a crucial role in promoting safety in electrical installations. These disconnecting switches are used to control the flow of electrical power and provide an emergency shut-off in case of faults or maintenance. By conforming to UL 98 standards, these switches can reliably protect personnel and electrical equipment from potential risks such as electric shock, arc flashes, and electrical fires.

Key Requirements of UL 98

UL 98 defines several requirements that disconnecting switches must meet in order to comply with the standard. One key requirement is the ability to safely interrupt and make currents under specified conditions. This ensures that the switch can handle high electrical loads without causing damage or compromising safety. The standard also covers provisions for device labeling, design features, short-circuit ratings, and endurance testing.

Testing and Certification

In order to achieve UL 98 certification, disconnecting switches undergo rigorous testing by accredited laboratories. These tests evaluate various aspects of the switch's performance, including its voltage rating, current carrying capacity, endurance, and mechanical strength. Manufacturers are required to submit samples for testing and ongoing factory inspections to ensure compliance with UL 98 requirements. Once certified, the product is marked with the UL symbol, indicating its compliance and providing confidence to end-users.