Safety of Surge Protection Devices

How to prevent catastrophic failures
BY DAVID KOMM, Mersen Electrical Protection
A surge protective device (SPD) plays an important role in protecting critical electronic components. However, all SPDs are sacrificial devices and, depending on the design and construction of the device, when it reaches end-of-life it could cause harm to your system.
SPD BACK STORY Historically, SPDs have provided adequate protection against high-level surges, however, they were also known for failing catastrophically. As a result, most SPDs were mounted on the equipment externally to help minimize component damage. In 2006, Underwriters Laboratories (UL), an international standards organization, updated their UL 1449 standard: “Surge Protective Devices”, which helped prevent the occurrence of catastrophic failures. When it was first introduced, many manufacturers struggled to pass the more stringent testing requirements in the updated UL 1449 standard.