For devices with screw shells, which terminal is connected to the grounded conductor?

The correct choice is the terminal connected to the screw shell, as this terminal is specifically designed for grounding purposes. In devices that utilize screw shells, the screw shell acts as a conductive outer enclosure that ensures safety by providing a grounded path for fault currents.

When properly installed, the terminal connected to the screw shell ensures that if there is a fault or short circuit within the device, the electrical current will flow to ground through this terminal, thereby preventing electric shock hazards. This is crucial for maintaining safety standards, ensuring that the device operates without risk of exposing users to live electrical components.

In contrast, other terminals may not provide this grounding function. For instance, the terminal on the left, the terminal with the highest voltage, and the terminal at the bottom may serve different roles in the electrical circuitry, such as providing power or connecting to different voltage sources, but they do not facilitate the grounding necessary for safety compliance as effectively as the terminal connected to the screw shell.