Schweitzer Engineering Laboratories SEL-9502 Contact Arc Suppressor

The SEL-9502 Contact Arc Suppressor from Schweitzer Engineering Laboratories is a compact, self-powered, two-terminal device that installs in parallel with a DC contact to suppress arcing in DC circuits up to 280 VDC. It protects a broad range of contact types—52A and 52B breaker contacts, trip and close contacts, lockout coils, auxiliary contacts, and control switches or PLC/SCADA interfaces—commonly found in protection, control, and automation schemes. The unit withstands interrupting 10 A of trip-coil current four times within three seconds, supporting trip, high-speed reclose, and delayed-reclose sequences without damaging the contacts it surrounds. Mounted in parallel with the contact, it reduces arc energy at opening, lowers wear and maintenance requirements, and minimizes voltage stress and DC noise, helping extend contact life and improve circuit reliability. Not for use with reed relays.