{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"S203-K20","brand":"ABB","brandSlug":"abb","productSlug":"S203-K20","canonicalUrl":"https://aoctrl.com/abb/S203-K20","factsUrl":"https://aoctrl.com/api/mcp/products/S203-K20","rawCanonicalId":null},"summary":{"shortDescription":"ABB S203-K20, 3-pole miniature circuit breaker, 20 A, Trip Curve K, 277 VAC, 10 kA interrupting rating, DIN rail mount.","salesMarkdown":"## 20 A, Curve K, 3-pole MCB for motor and transformer branch circuits The K curve provides a higher magnetic trip threshold (typically 8–12× In) than a C curve (5–10× In), making it suitable for loads with moderate inrush — motor starters, transformer primaries, and solenoid banks — where nuisance tripping on a C curve would be a problem. The 20 A continuous rating and 10 kA interrupting capacity at 277 VAC cover most light-industrial and commercial branch circuits. The 3-pole footprint matches the common 3-module width (52.5 mm) of ABB's S200 series. Busbar comb and accessory terminals (auxiliary contacts, shunt trip, undervoltage release) are shared across the S200 family, so a panel already built around S203-C10 or S203M-C50 accepts the S203-K20 without rewiring the busbar or reordering accessories. The S203-K20 carries a current lifecycle stage. No official successor has been announced; the S200 series remains the active platform.","metaTitle":"S203-K20 Miniature Circuit Breaker, 3P, 20A, Curve K","metaDescription":"S203-K20 3-pole MCB, 20 A, Trip Curve K, 277 VAC, 10 kA interrupting rating. Current lifecycle stage. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["3-Pole MCB (DIN Rail)"],"specifications":{"Amps":"20","Type":"Trip Curve K","Poles":"3","title":"S203-K20","Mounting":"DIN Rail","Volts AC":"277","description":"Miniature Circuit Breaker, 3P, 20A|Miniature Circuit Breaker, 3 Pole, 20 Amp","lifecycle_stage":"current","Interrupt Rating AC":"10 kA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$20.32","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/1b888e9d473400bd32917551d1de57a0.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Where can I buy S203-K20 and how is it quoted?","answer":"Sourced through independent distribution. Submit an RFQ for current availability and pricing — confirmed at quote time, no stock or price figures on this page."},{"question":"What is the closest functional second-source to S203-K20?","answer":"The S203-C10 shares the same 3-pole DIN-rail footprint and 10 kA interrupting rating but uses a C curve (5–10× In) instead of K (8–12× In). If the branch circuit feeds a motor or transformer, the K curve is the better fit; for general-purpose resistive or lighting loads, the C curve works. Both use the same accessories and busbar."},{"question":"Will S203-K20 drop into a panel specified around S203-C10 without rewiring?","answer":"Yes — same 3-pole width, same DIN-rail mount, same busbar comb pattern. No rewiring needed; just swap the MCB."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/abb/S203-K20","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/S203-K20 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}