Automatic Circuit Reclosers (ACRs) are a class of switchgear which is designed for use on overhead electricity distribution networks to detect and interrupt momentary faults. Also known as Reclosers or Auto-reclosers, ACRs are essentially medium voltage rated circuit breakers with integrated current and voltage sensors and a protection relay, optimized for use as an overhead network distribution protection asset. Commercial ACR's are governed by the ANSI/IEEE C37.60, IEC 62271-111 and IEC 62271-200 standards. In ANSI countries three major classes of operating voltage are 15.5 kV, 27 kV and 38 kV.