Electrician's Licensing Practice Exam

Does a TVSS provide adequate protection against lightning strikes?

1. Yes

2. No

3. Only in certain conditions

4. Only for indirect strikes

The correct answer is: No

A Transient Voltage Surge Suppressor (TVSS) is designed to protect electrical equipment from voltage spikes, such as those caused by lightning strikes, power surges, or other transient events. However, the protection offered by a TVSS is limited and is typically more effective for smaller surges rather than direct lightning strikes. Lightning strikes can induce extremely high energy levels that exceed the capacity of most TVSS systems. A direct lightning strike can carry millions of volts and kilojoules of energy, which can overwhelm any surge protection device. While a TVSS might offer some level of protection against voltage transients produced by nearby strikes or lesser surges, it is not sufficient to handle the full impact of a direct lightning strike. In contrast to a TVSS, additional protective measures such as lightning rods, grounding systems, and whole-building surge protection devices are recommended to help mitigate the risks associated with direct lightning strikes. These systems work together to safely divert the energy of a lightning strike away from sensitive equipment and into the ground. Consequently, while a TVSS can be part of an overall protective strategy, it does not provide adequate protection against the full force of a lightning strike directly hitting a structure or system.