Layered surge protection strategies to safeguard electronics from lightning, utility switching, and internal loads.
Surge protection is one of the most misunderstood aspects of electrical system safety. Below are answers to the questions we hear most often from facility managers and engineers.
A solid ground is necessary for surge protection devices to function, but it doesn't replace them. Without an SPD, surge current will find its own path to ground — and that path often runs straight through your electronic equipment, exceeding the dielectric strength of internal components and causing failure.
A UPS provides clean, uninterruptible power to critical equipment, but it offers little protection for communication and control lines, and minimal coverage for the broader network. The surge suppression built into even large UPS units typically tops out at 25–40kA. Our smallest AC entrance protector starts at 70kA, with units available up to 600kA.
Lightning is only one source of transient surges. Today's facilities run far more interconnected control and communication devices than previous generations, and modern electronics are significantly more susceptible to transient damage. Many surge events go unnoticed until cumulative damage causes an unexpected failure.
Not significantly. For most operations, a single surge event that takes down a control or network system — even once in a decade — costs more in downtime and repairs than comprehensive protection would have over that entire period. System availability is the real risk, not just equipment damage.
Low-voltage control and communication interfaces connect directly to sensitive driver and receiver chips with very little tolerance for voltage differences. These interfaces are statistically more vulnerable to surge damage than power supplies, which typically have built-in filtering and operate at higher voltages. This holds true even when all data lines remain inside the building, where induced voltages from nearby strikes or differences in AC voltage references between connected devices can still cause damage.
Carrier-provided protection is designed primarily for personal safety — preventing lightning from migrating onto their infrastructure and causing injury. It provides primary protection only, and does not address the secondary protection your equipment requires at the point of use.
Metal housings carry a risk of fire or explosion if a TVSS unit fails. UL1449 2nd Edition requires that TVSS units fail safely, and all ASC products are independently UL-tested to that standard. The thermoplastic enclosure is NEMA 4X rated — corrosion-proof, UV-stabilized, and suitable for indoor or outdoor installation. The clear gasket door lets you check module status without opening the enclosure.
