What the ratings mean for fit
The ABB S202-K3 is a 2-pole miniature circuit breaker rated 3 A, Trip Curve K, with a 6 kA interrupting capacity at 277 VAC. It is classified as a supplemental protector per UL 1077 and CSA 22.2.
Integration note
Snap-on DIN rail mounting (per) — the S202-K3 occupies two 18 mm module widths in a standard enclosure. The K-curve magnetic trip at 8–12x In means it will hold steady through a motor start but clear quickly on a hard short. For panel builders: the 6 kA SCCR at 277 VAC is adequate for most control panels fed by a transformer with limited fault current; verify the available fault current at the panel's point of supply before committing to the BOM.