ABB S203-K3 Circuit Breaker

ABB S203-K3 is a three-pole miniature circuit breaker from the S200 family (catalog number 2CDS253001R0317) with a nominal current rating of 3 A and a curve K thermal-magnetic trip, designed to protect 3‑phase circuits from overloads while reducing nuisance trips on motor starts. It is DIN-rail mountable and built with finger-safe, multi-function terminals for straightforward panel installations in commercial and industrial environments. The device offers a short-circuit current rating (Icu) up to 6 kA and is rated for voltages up to 277 VAC (phase-to-neutral) / 480 VAC (phase-to-phase), making it compatible with common 480Y/277 power systems. Construction features include robust internal metallic components and flame-retardant, halogen-free materials (V0 internal components), aligning with safety and environmental considerations. The S203-K3 carries UL 1077 and CSA 22.2 marks for supplementary protection, and its exact ABB part number is 2CDS253001R0317, confirming its place in ABB’s compact protection lineup for three-phase circuits. This model is well suited for distribution boards and control panels where compact, reliable protection of three-phase loads is required without external fusing.