The ABB S201-K2 is a 1-pole miniature circuit breaker rated 2 A with a K trip curve, designed for DIN rail mounting in control panels and distribution boards. It carries a 6 kA interrupting capacity at 277 VAC and is listed as a UL 1077 supplemental protector — meaning it protects downstream equipment rather than serving as a service-entrance disconnect. The K curve provides a higher magnetic trip threshold than B or C curves, making it suitable for loads with moderate inrush, such as small motors, transformers, or solenoid banks.
K curve and application fit
The K curve trips magnetically at 8–12× rated current, compared to 5–10× for C curve and 10–14× for D curve. At 2 A, that means the magnetic trip fires between 16 A and 24 A. This gives you enough headroom to start a small motor or charge a capacitive load without nuisance tripping, while still providing short-circuit protection. For purely resistive loads or general-purpose branch circuits, a C curve would trip faster — K is the right choice when you know the load draws a brief inrush above 10× the continuous rating.
Compliance and approvals
Listed under UL 1077 (supplemental protection) and CSA 22.2, the S201-K2 is accepted in North American industrial panels where a branch-circuit-rated breaker is not required. It also carries CE marking for European markets. RoHS and REACH compliance documentation is available on request.