{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SU1656-6KV40","brand":"Siemens","brandSlug":"siemens","productSlug":"5SU1656-6KV40","canonicalUrl":"https://aoctrl.com/siemens/5SU1656-6KV40","factsUrl":"https://aoctrl.com/api/mcp/products/5SU1656-6KV40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens 5SU1656-6KV40 FI/LS protector, Type A (PSE/SSF), 1+N-pole, B-curve 40A, 300mA residual, 6kA, 70mm wide.","salesMarkdown":"The Siemens 5SU1656-6KV40 is a combined residual current device and miniature circuit breaker (FI/LS protector) in a single 70mm-wide module. It packs Type A residual current detection at 300mA with a B-curve 40A overcurrent trip and 6kA breaking capacity into a 1+N-pole format — one protected phase plus switched neutral. The Type A classification means it detects pulsating DC residual currents in addition to sinusoidal AC — essential on circuits feeding single-phase electronics, VFDs, or switching power supplies where a pure AC-sensitive (Type AC) device would miss fault current. The 300mA residual threshold is sized for fire protection rather than personal shock protection (30mA is the touch-safe limit); this unit goes into sub-distribution or feeder circuits where the goal is arc-flash and cable-fire prevention, not direct personnel protection. The B-curve 40A overcurrent characteristic trips between 3x and 5x rated current (120-200A magnetic release), suited for resistive and general-purpose loads — lighting, socket outlets, small motor circuits — where inrush is moderate. The 1+N-pole configuration switches the phase and disconnects the neutral, leaving the neutral pole unswitched in the off state on some variants — check the wiring diagram for your specific board layout. The 70mm width (4 module spaces on a DIN rail) is wider than a standard single-pole MCB (17.5mm) because the RCD core and trip electronics occupy the extra space. Snaps onto a 35mm DIN rail in a distribution board or sub-panel. The 70mm width means it occupies four 17.5mm module positions — plan the rail fill accordingly, especially when combining with other RCBOs or accessories. Supply-side connection is typically from the busbar; load-side terminals accept up to 25mm² conductor. No separate RCD block needed upstream — this is a single-device solution for combined overcurrent and residual protection.","metaTitle":"Siemens 5SU1656-6KV40 FI/LS Protector Type A, 40A B-Curve, 3","metaDescription":"Siemens 5SU1656-6KV40 FI/LS protector, Type A, 40A B-curve, 300mA residual, 6kA breaking capacity. Current lifecycle stage. Quoted to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Residual Current Breakers (RCCB/RCBO)"],"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=283862&mlfb=5SU1656-6KV40","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SU1656-6KV40/alternatives.json"},"ai":{"faq":[{"question":"What is 5SU1656-6KV40's listed description?","answer":"The official description is: FI/LS-PROTECTOR TYPE A (PSE/SSF), D=70MM IFN 300MA, 6KA, 1+N-POLE B 40A. This is a combined RCD/MCB in a 70mm-wide module, Type A residual sensitivity at 300mA, 6kA breaking capacity, 1+N poles, B-curve 40A overcurrent trip."},{"question":"Where can I buy the 5SU1656-6KV40 and get current pricing?","answer":"The 5SU1656-6KV40 is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm commercial response."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SU1656-6KV40","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/5SU1656-6KV40 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}}