To what does the term "follow current" relate in the context of surge arrestors?

The term "follow current" in the context of surge arrestors refers to the current that continues to flow after the surge arrestor has discharged a surge event. When a surge arrestor activates during a voltage spike, it conducts current to protect equipment by diverting excess voltage away. Following this event, there may still be a residual current that flows through the surge arrestor or the connected equipment, referred to as follow current. This is critical to understand because even after a surge is mitigated, the potential for damage or further surges can still exist if this follow current is not adequately managed. Recognizing this concept helps in designing systems that can effectively handle both initial surge events and any subsequent currents that may pose additional risks to electrical systems.