What the ratings mean for fit
The ABB S203-K6 is a 3-pole miniature circuit breaker from the S200 series, rated 6 A continuous with a Trip Curve K characteristic. The K-curve trips magnetically between 8 and 12 times rated current — designed for inductive loads like motors and transformers where inrush current exceeds a C-curve's tolerance but doesn't need the high-end delay of a D-curve. At 6 A, it protects a 3-phase motor drawing roughly 2.2 kW at 480 V, sized for the branch circuit rather than the main feeder. Rated 480Y/277 V AC with a 6 kA interrupting capacity, this breaker clears phase-to-phase and phase-to-neutral faults up to 6 kA without welding its contacts. The 6 kAIC is adequate for most light-industrial panelboards fed from a 75 kVA or smaller transformer; verify the available fault current at the installation point before committing the BOM line. Classified as a UL 1077 supplemental protector — not a branch-circuit rated UL 489 breaker. That means it's intended for internal panel protection of control circuits, HVAC equipment, or machine-tool sub-circuits where the upstream branch breaker already provides the service entrance protection. CSA 22.2 listed for Canadian installations.
DIN-rail integration and panel fit
Snaps onto standard 35 mm DIN rail per EN 60715. Three-pole width occupies 54 mm (3 x 18 mm per pole) of rail space — plan the enclosure fill factor accordingly. The S200 series uses a tunnel-style screw terminal accepting 0.5 to 25 mm² (AWG 20–4) copper wire; torque to 2.5 Nm per the terminal marking.