Where should the GEN RESET switches be positioned for a Ground Power Unit (GPU) start?

For a Ground Power Unit (GPU) start, the GEN RESET switches should be positioned to the "Off" position to ensure proper system operation and safety protocols during the startup process. When the switches are in the "Off" position, it prevents any potential issues that could arise from having the generators engaged while utilizing external power. This allows the aircraft to safely rely on the ground power for starting the engines without involving the aircraft's own generators, which are not yet online.

In contrast, having the switches in the "NORM," "On," or "Standby" positions could lead to unintended electrical system engagement, potentially causing complications or failures during the startup sequence when using external power. Thus, setting the GEN RESET switches to "Off" is a critical procedure during a GPU start to ensure safety and the integrity of the electrical systems involved.