The ABB S201PR-K5 is a single-pole miniature circuit breaker from the S200PR RTT series, rated 5 A continuous at 277 VAC with a 10 kA interrupting capacity. The Trip Curve K characteristic means the magnetic trip threshold sits at 8–12× rated current — designed for inductive loads like motor starters, solenoid valves, and transformer primaries where inrush current is high but sustained overloads are rare.
Where it sits in the panel
The single-pole footprint takes one module width (17.5 mm), so it fits tightly in a crowded enclosure. Rated for 277 VAC line-to-neutral circuits, common in North American commercial lighting and small motor branch circuits.