Client: Rich Mountain Electric Cooperative

Location: Mena, AR

Description:
TOTH designed Crystal Hill Substation which is a 10 MVA distribution substation that serves mostly residential load through four 13.2 kV feeders. The substation is fed from a radial 69 kV transmission line that terminates on a box bay dead-end structure. A 69 kV gas circuit breaker provides protection and sectionalizing for the 69 kV transmission line. A second gas breaker isolates the transformer from potentially destructive currents. The 13.2 kV feeders are protected by vacuum circuit reclosers. The distribution structure features a transfer bus to allow for uninterrupted service while performing recloser maintenance. A pre-fabricated concrete control building houses digital protective relaying equipment, a 48 Vdc battery backup system, and auxiliary ac and dc load centers for the station. Structures and bus were designed for simplified utilization of a mobile substation during transformer maintenance and failure events.