How is a Current Transformer (CT) typically connected in a circuit?

A Current Transformer (CT) is typically connected in series within a circuit. This connection method is crucial because a CT is designed to measure the current flowing through a conductor by producing a proportional output current that is suitable for instrumentation and protection applications.

When configured in series, the CT allows the same current that is present in the primary circuit to flow through its primary winding. This enables the CT to accurately transform and scale down this current to a lower value in its secondary winding, making it safer and more manageable for monitoring or control purposes. The output of the CT can then be connected to measurement instruments, relays, or data acquisition systems.

Connecting a CT in parallel would not provide accurate measurements of the primary current since the current flowing through a parallel connection would be different from the total current in the primary circuit. The other options, such as a loop connection or a star configuration, do not align with standard practices in connecting current transformers and would not yield the desired functionality of current measurement.