Will a sectionalizer interrupt fault current?

A sectionalizer is a device used in electrical distribution systems to automatically isolate sections of the network during a fault without interrupting normal operation. Its primary function is to work in conjunction with a protective device, such as a fuse or circuit breaker, which is responsible for interrupting fault current.

When a fault occurs, the protective device detects the excessive current and operates to interrupt the fault. The sectionalizer monitors this event and, if it detects that the protective device has opened due to a fault, it will wait for a predetermined period to confirm that the fault remains present before it operates to isolate the section of the line. This coordination allows the sectionalizer to minimize the impact of faults on the system without directly interrupting the fault current itself.

Therefore, sectionalizers do not interrupt fault current; they operate based on the actions of upstream protective devices to manage system reliability and minimize outages. This distinction is crucial for understanding the role of sectionalizers in a power distribution system.