What can cause transient voltage events in an electrical system?

Transient voltage events are sudden spikes or changes in voltage that can occur in an electrical system, potentially leading to equipment damage and operational issues. The correct choice highlights lightning and switching operations as primary causes of these transient voltage events.

Lightning strikes create high-energy surges when they hit electrical lines or components, leading to a rapid increase in voltage known as a surge. Additionally, switching operations—such as the operation of circuit breakers, relays, or disconnect switches—can cause sudden changes in current flow, which in turn generate transient voltages due to inductive kickback or changes in the magnetic field associated with the current. These events can create brief but significant voltage spikes that may adversely affect sensitive electrical equipment.

In contrast, steady electrical loads do not contribute to transient voltages as they maintain a consistent demand on the electrical system. Fluctuations in power supply frequency affect the stability and performance of electric systems but do not directly cause transients in the same manner that lightning or switching events do. Inconsistent grounding methods may introduce other electrical issues, such as noise or interference, but they do not inherently generate transient voltage events like direct lightning strikes or the effects of rapid circuit switching do.