{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"S203-K3","brand":"ABB","brandSlug":"abb","productSlug":"S203-K3","canonicalUrl":"https://aoctrl.com/abb/S203-K3","factsUrl":"https://aoctrl.com/api/mcp/products/S203-K3","rawCanonicalId":null},"summary":{"shortDescription":"ABB S203-K3, 3-pole miniature circuit breaker, 3A, Trip Curve K, 277 VAC, 10 kA interrupting rating, DIN rail mount.","salesMarkdown":"The K-curve is designed for inductive loads with high inrush currents — think motor starters, solenoid valves, or transformer primaries — where a B- or C-curve would nuisance-trip on startup. Three-pole construction means it protects a three-phase load or three independent single-phase circuits off the same DIN rail. At 277 VAC phase-to-neutral, it's common in North American lighting panels where the line-to-neutral voltage is 277 V. The K-curve's magnetic trip threshold — typically 10–14x rated current — handles the inrush of small motor loads or lighting ballasts without dropping out on startup. For a maintenance tech swapping out a failed S203-C8 in the same panel: the footprint and DIN-rail mount are identical, but the trip curve is different — C-curve trips at 5–10x In, K-curve at 10–14x In — so verify the load's inrush profile before substituting.","metaTitle":"ABB S203-K3 Miniature Circuit Breaker, 3-Pole, 3A, K-Curve","metaDescription":"ABB S203-K3 3-pole MCB, 3A, K-curve, 277VAC, 10kA interrupting rating. Current lifecycle stage. Quoted to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Miniature Circuit Breakers (MCB)"],"specifications":{"Amps":"3","Type":"Trip Curve K","Poles":"3","Mounting":"DIN Rail","Volts AC":"277","lifecycle_stage":"current","Interrupt Rating AC":"10 kA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$20.32","priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/1b888e9d473400bd32917551d1de57a0.pdf","sourceUrl":null,"alternativesUrl":"https://aoctrl.com/api/mcp/products/S203-K3/alternatives.json"},"ai":{"faq":[{"question":"How do I get current pricing and availability for S203-K3?","answer":"We source and quote the S203-K3 to order against an RFQ. Submit a request and we'll confirm current pricing and availability at quote time."},{"question":"Will S203-K3 drop into a panel that was specified around S203-C8 without rewiring?","answer":"The S203-K3 shares the same 3-pole DIN-rail footprint and 277 VAC rating as the S203-C8, so it fits mechanically. But the trip curve differs: K-curve (10–14x In) handles higher inrush than C-curve (5–10x In). Only substitute if the load's inrush matches the K-curve — otherwise you risk nuisance trips or loss of coordination."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/abb/S203-K3","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-K3 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}}