Fault locator and selectivity sensor

A sensor for a power distribution system includes: a conductor; a core proximate the conductor; and a reed switch adjacent the core, the reed switch in electrical communication with an electronic trip unit. A power distribution system includes: an upstream circuit breaker including an electronic trip unit; a downstream circuit breaker in electrical communication with the upstream circuit breaker; a first sensor positioned downstream from the downstream circuit breaker, the first sensor includes: a conductor in electrical communication with the downstream circuit breaker; a core located proximate the conductor; and a reed switch adjacent the core, the reed switch in electrical communication with the electronic trip unit.