What conditions will interrupt the EPBIT when introduced with an initial AC source?

The correct answer pertains to the operation of the electric systems in the aircraft, specifically in reference to the Emergency Power Bus Isolation Transformer (EPBIT). When the initial AC source is introduced, the EPBIT is responsible for managing power distribution.

One crucial aspect of the EPBIT’s function is that it will be interrupted when there is a significant load introduced to the system. The operation of hydraulic pumps represents a high demand on the electrical system, as these pumps require substantial power to function. When hydraulic pumps begin operation, they can exceed the capacity supported by the EPBIT, leading to its interruption as a protective measure to prevent overload or system failure.

In contrast, while landing gear deployment and the flight control mode panel switch cycle may have operational impacts, they do not exert the same level of electrical load as hydraulic pump operation. An AC supply interruption directly impacts the power supply but does not qualify as a load demand that would interrupt the EPBIT. Therefore, the introduction of hydraulic pump operation is the condition that would cause interruption of the EPBIT when an initial AC source is introduced.