Schweitzer Engineering Laboratories, Inc. (SEL) has announced the immediate availability of arc-flash detection (AFD) capability in the SEL-751A Feeder Protection Relay, providing fully automatic protection against dangerous arc-flash events. Without AFD, the arc flash can cause severe personal injury, extensive equipment damage, and lengthy system outages. In contrast, AFD interrupts power to the arc flash before it can cause significant damage. Anyone with metal-clad switchgear will benefit from using the SEL-751A with AFD.
The SEL-751A AFD solution uses fiber-optic, arc-flash light sensors to detect the light produced by an arc-flash event. To prevent false tripping, the SEL-751A looks for an overcurrent that coincides with the light flash. When both conditions are met, the SEL-751A sends a trip signal to the circuit breaker in as fast as 2 ms. This fast tripping significantly reduces the damage-causing energy released by the arc-flash event.
“As a result of new NESC and NFPA requirements, many utilities and industrial companies are looking for ways to mitigate arc-flash hazards. The SEL-751A can reduce these hazards by stopping an arc-flash event before it escalates into a catastrophic, high-energy event,” said SEL R&D Manager Angelo D’Aversa.