A circuit that is not affected by a fault is described as ______.

• A. Unfaulted
• B. Faulted
• C. Isolated
• D. Operational

Answer: (A)

Understanding fault status of a circuit: if a circuit has no fault present, it remains in its normal, designed condition and is described as unfaulted. That means there are no abnormal currents, voltages, or disturbances affecting it within that portion of the system. A faulted circuit, by contrast, has some abnormal condition such as an overcurrent, short, or open that would change its behavior. Isolated describes removing or disconnecting the circuit from the rest of the system to prevent fault propagation, not simply that it isn’t affected by a fault. Operational means the circuit is functioning, but that alone doesn’t guarantee it’s free from faults. So the term that best fits “not affected by a fault” is unfaulted.