The purpose of overcurrent protection of capacitors is for which protection?

• A. Inrush
• B. Ground-fault
• C. Overload
• D. Short circuit

Answer: (D)

The main idea is protecting a capacitor from excessive current that can occur during faults. Overcurrent protection is there to interrupt the circuit when current spikes beyond what the capacitor can safely handle, preventing overheating, venting, or explosion from a fault condition. A short circuit creates a near-zeroin impedance path, causing a massive current surge that these protection devices are designed to detect and trip for. Inrush limiting deals with the normal charging surge when a capacitor is first connected, not with protecting against fault-induced current; overload is a sustained excessive current scenario, which is also important but is ultimately a broader fault condition, whereas the most immediate, dangerous overcurrent event is a short circuit. Ground-fault relates to leakage to earth and is not the primary target of overcurrent protection for capacitors.