What provides overcurrent protection for the secondary leads in a CSP transformer?

The provision of overcurrent protection for the secondary leads in a CSP (Containerized Substation Package) transformer is typically achieved through the use of a low voltage circuit breaker. This type of circuit breaker is designed to interrupt the electrical flow in the event of an overcurrent condition, thereby preventing damage to the transformer and the connected equipment.

Low voltage circuit breakers have specific ratings that can be selected based on the expected load and the characteristics of the transformer. When an overcurrent occurs, such as during a fault condition or when there is an overload, the circuit breaker will sense the excess current and automatically trip, disconnecting the power supply and protecting the circuit. This automatic action is crucial for ensuring both safety and equipment longevity in electrical systems.

Other protective devices, like fuse links or safety switches, serve different purposes and may not provide the same level of responsiveness or adjustability for overcurrent scenarios as a low voltage circuit breaker. For example, fuses need to be replaced after they blow, while safety and disconnect switches are more about isolating equipment rather than providing instantaneous overcurrent protection.