Rail Fault Protection

Railroad systems are increasingly required to operate in common corridors with power transmission and distribution lines presenting new equipment protection challenges. Damaging AC faults caused by failure of power utility equipment on overhead power lines present high-energy, long-duration events that typical lightning surge protective devices are not capable of withstanding. These events pose a risk to track-connected signaling and crossing warning systems as well as other protective equipment.

Dairyland’s Overwatch HEFPD is a new class of device, designed using our decades of experience in high-energy applications. With a design featuring Dairyland’s proven solid-state technology, Overwatch can withstand the powerful, long-duration events caused by AC faults, keeping sensitive track-connected equipment protected. Overwatch is rated up to 4000 amps for a 12 cycle (0.2 second) duration AC fault event as defined in AREMA 11.3.7, while also meeting the applicable requirements of primary surge protection as defined in AREMA 11.3.1.