In what configuration is a booster transformer connected to the primary line?

A booster transformer is designed to improve or boost the voltage levels in an electrical system, particularly where long transmission lines result in voltage drops. It is connected in parallel with the primary line to enhance the overall voltage supplied to the circuit loads without interrupting the primary line's continuity.

When connected in parallel, the booster transformer allows the primary side to maintain its path to the electrical source while the transformer injects additional voltage as needed to compensate for any losses and ensure that users receive adequate voltage levels. This configuration enables better regulation of voltage throughout the distribution network, which is critical in ensuring the efficiency of power delivery to end users.

Connecting a transformer in series would mean that all the current flowing through the line would pass through the transformer, which is not the case for booster transformers. Similarly, configurations like a closed loop or reverse connection do not accurately describe how a booster transformer functions in relation to the primary line. Hence, the parallel connection is the appropriate and effective setup for optimizing voltage levels in electrical systems.