What is the required conductor ampacity for ungrounded conductors supplying a capacitor?

The correct choice involves understanding the ampacity requirements specific to ungrounded conductors supplying a capacitor. When capacitors are used in electrical systems, they can create conditions that necessitate higher current capacities than the capacitor's rated current. Specifically, the National Electrical Code (NEC) dictates that ungrounded conductors supplying capacitors should have an ampacity of 135% of the rated current of the capacitor itself.

This percentage is determined to account for factors such as inrush current, which is the initial surge of current that occurs when a capacitor is charged. The increased ampacity ensures that the conductors can handle this surge without overheating or risking damage. Therefore, using 135% of the capacitor's rated current for sizing the conductors helps maintain safety and reliability within the electrical system.

Understanding these requirements helps ensure that capacitors are properly integrated into circuits while minimizing risks associated with overheating and electrical faults.