What happens to the main batteries and engine driven generators when a GPU is connected and powering the aircraft?

When a Ground Power Unit (GPU) is connected to the Dassault Falcon 2000LXS and is powering the aircraft, the main batteries and engine-driven generators are automatically disconnected from the electrical system. This automatic disconnection occurs to prevent any back-feed of power between the GPU and the aircraft's internal power system, ensuring that the GPU can effectively provide power without interference from the aircraft's batteries or generators.

In cases where a GPU is utilized, the system is designed for efficient power management, allowing the GPU to supply the necessary electrical power for avionics and other systems without the added burden of the aircraft's batteries or generators being active. This minimizes wear and tear on the onboard systems while providing a stable power source during ground operations such as preflight checks or maintenance tasks.

The other options do not correspond correctly to the aircraft's automatic systems designed for managing power sources effectively when a GPU is connected.