{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"S201-K4","brand":"ABB","brandSlug":"abb","productSlug":"S201-K4","canonicalUrl":"https://aoctrl.com/abb/S201-K4","factsUrl":"https://aoctrl.com/api/mcp/products/S201-K4","rawCanonicalId":null},"summary":{"shortDescription":"ABB S200 series, miniature circuit breaker, S201-K4, 4 A, 1-pole, Trip Curve K, 277 VAC, 6 kA interrupting rating, DIN rail mount.","salesMarkdown":"Curve K is a specialty magnetic trip curve designed for highly inductive loads — think motor starters, solenoid valves, or transformer primaries where the inrush current is high but short. The K curve's magnetic trip threshold (typically 8–12× rated current) lets it ride through those inrush spikes without nuisance tripping, unlike a Curve C (5–10×) or Curve D (10–14×) which might trip on a motor start or hold too long on a fault. ## Where it's used — the deployment context This is a DIN-rail mounted supplemental protector per UL 1077, not a branch-circuit rated breaker per UL 489. That distinction matters: UL 1077 devices are intended for overcurrent protection within equipment — control panels, HVAC units, machine tool enclosures — not as the main service disconnect. In a panel, it protects a single 4 A load circuit, typically a contactor coil, a small power supply, or a PLC output group. Listed under UL 1077 as a supplemental protector and CSA 22.2, the S201-K4 carries the safety certifications needed for North American panel builds. The S200 series also holds IEC/EN 60898 and IEC/EN 60947-2 ratings for global installations, though the specific listing here is UL/CSA. RoHS and REACH compliance documentation is available from the manufacturer upon request — standard for ABB's current-production S200 line.","metaTitle":"S201-K4 Miniature Circuit Breaker, 4A, 1P, Curve K, 277VAC","metaDescription":"S201-K4 miniature circuit breaker, 4 amps, 1 pole, Trip Curve K, 277 VAC, 6 kA interrupting rating. UL 1077 supplemental protector. Current lifecycle. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["1-Pole MCB (DIN Rail)"],"specifications":{"Amps":"4","Type":"Trip Curve K","Poles":"1","Mounting":"DIN Rail","Volts AC":"277","lifecycle_stage":"current","Interrupt Rating AC":"6 kA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$37.97","priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/1b888e9d473400bd32917551d1de57a0.pdf","sourceUrl":null,"alternativesUrl":"https://aoctrl.com/api/mcp/products/S201-K4/alternatives.json"},"ai":{"faq":[{"question":"What is the S201-K4's interrupting rating?","answer":"The S201-K4 is rated for 6 kA interrupting capacity at 277 VAC, which is the maximum fault current it can safely clear."},{"question":"What does Trip Curve K mean on the S201-K4?","answer":"Trip Curve K is a magnetic trip characteristic with a threshold of 8–12 times rated current, designed to handle high inrush from inductive loads like motors and transformers without nuisance tripping."},{"question":"Where can I buy the S201-K4?","answer":"The S201-K4 is sourced and quoted to order against an RFQ through independent distribution, with availability and current pricing confirmed at quote time."},{"question":"Will the S201-K4 drop into a panel designed for the S201M-C10?","answer":"Mechanically yes — both are 1-pole DIN-rail breakers in the same S200 family footprint. But the K curve on the S201-K4 has a different magnetic trip threshold than the C curve on the S201M-C10, so verify the load's inrush characteristics before swapping. The S201M-C10 is also rated 10 A, not 4 A, so the ampacity is different."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/abb/S201-K4","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/abb/S201-K4 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:15:54.622Z","lastPublished":"2026-09-02T08:15:54.622Z","indexable":true}}