{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RB1025-1SB0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RB1025-1SB0","canonicalUrl":"https://aoctrl.com/siemens/3RB1025-1SB0","factsUrl":"https://aoctrl.com/api/mcp/products/3RB1025-1SB0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RB1025-1SB0 electronic overload relay, 3...12 A, Class 10, screw connection, manual reset only, size S0, for contactor mount.","salesMarkdown":"The Siemens 3RB1025-1SB0 is an electronic overload relay in the SIRIUS 3RB10 series, rated for 3...12 A motor protection with Class 10 trip characteristic. It mounts directly on a contactor in size S0, using screw terminals, and is configured for manual reset only. The 3...12 A current range covers small to mid-size induction motors — think 2.2 kW at 400 V three-phase, or a 5 HP motor at 480 V. Class 10 trip means it will ride through normal starting inrush on most pump, fan, and compressor loads (typical start time under 10 seconds), but will trip before the motor overheats on a stalled rotor. The manual reset only configuration means the relay latches after a fault and requires a physical button press to re-close the circuit — no auto-restart, which is the safer choice for unattended or hazardous machinery where unexpected re-start could injure personnel. Size S0 is the standard Siemens contactor footprint for this current class. The relay snaps onto the contactor without additional hardware, and the screw terminals accept 0.5...4 mm² wire. Wiring is straightforward: the three-phase motor leads pass through the relay's current sensing apertures, and the N/C trip contact (95-96) breaks the contactor coil circuit on overload. Verify the contactor's coil voltage matches the control circuit before wiring the trip contact.","metaTitle":"Siemens 3RB1025-1SB0 Electronic Overload Relay, 3-12A, Class","metaDescription":"Siemens 3RB1025-1SB0 electronic overload relay, 3...12 A, Class 10, screw connection, manual reset, size S0. Current lifecycle stage. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"lifecycle_stage":"current"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=379529&mlfb=3RB1025-1SB0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RB1025-1SB0/alternatives.json"},"ai":{"faq":[{"question":"What is the closest alternative to the 3RB1025-1SB0 in this family?","answer":"Within the same 3RB10 series, the closest alternative would be a variant with a different current range (e.g., 1...3.2 A or 8...32 A) or with automatic reset instead of manual. The size S0 footprint and Class 10 characteristic are shared across the family. No pin-compatible direct alternative exists outside the 3RB10 series without changing the contactor mount."},{"question":"Where can I buy the 3RB1025-1SB0?","answer":"The 3RB1025-1SB0 is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RB1025-1SB0","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/siemens/3RB1025-1SB0 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}}