{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"0451.750NRL","brand":"Littelfuse Inc.","brandSlug":"littelfuse-inc","productSlug":"0451.750NRL","canonicalUrl":"https://icboms.com/littelfuse-inc/0451.750NRL","factsUrl":"https://icboms.com/api/mcp/products/0451.750NRL","rawCanonicalId":null},"summary":{"shortDescription":"Littelfuse Inc. NANO²® 451 series, Board Mount (Cartridge Style Excluded) fuse, Surface Mount, 2-SMD Square End Block package, 750 mA, 125 VAC/125 VDC, Fast Blow, 50 A breaking capacity.","salesMarkdown":"## 750 mA protection for 125 V rails The Littelfuse 0451.750NRL is a 750 mA fast-blow fuse from the NANO² 451 series, rated for 125 VAC and 125 VDC circuits. With a 50 A breaking capacity at rated voltage, it safely interrupts overcurrents up to that level without rupturing the package — critical for clearing hard shorts on a 125 V bus without cascading to upstream protection. ## Fast-blow response and surge tolerance The fast-blow characteristic means the fuse element opens quickly on sustained overloads, protecting downstream semiconductors and thin traces from thermal damage. The melting I²t of 0.185 quantifies the energy needed to melt the element — useful for sizing the fuse against inrush currents from capacitive loads or motor starts without nuisance opening. DC cold resistance measures 0.245 Ohms, which at 750 mA produces a voltage drop of roughly 184 mV — negligible for most 125 V circuits but worth factoring into low-voltage sense paths. ## Surface-mount footprint and thermal environment Housed in a 2-SMD square end block package measuring 6.10 mm x 2.69 mm x 2.69 mm, the 0451.750NRL mounts directly to a PCB pad pattern. The surface-mount format suits automated pick-and-place assembly; the square end block provides stable solder joints under vibration.","metaTitle":"Littelfuse 0451.750NRL NANO² 451 Fuse, 750 mA, 125 V","metaDescription":"Littelfuse 0451.750NRL NANO² 451 surface-mount fuse, 750 mA, 125 VAC/DC, fast-blow, 50A breaking capacity. Active lifecycle, CSA/UL approved. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Protection"],"specifications":{"Mfr":"Littelfuse Inc.","Color":"-","Series":"NANO²® 451","Package":"Tape & Reel (TR); Cut Tape (CT)","Fuse Type":"Board Mount (Cartridge Style Excluded)","Melting I²t":"0.185","Mounting Type":"Surface Mount","Response Time":"Fast Blow","Package / Case":"2-SMD, Square End Block","Product Status":"Active","Approval Agency":"CSA, UL","lifecycle_stage":"unknown","Size / Dimension":"0.240\\\" L x 0.106\\\" W x 0.106\\\" H (6.10mm x 2.69mm x 2.69mm)","DC Cold Resistance":"0.245 Ohms","Voltage Rating - AC":"125 V","Voltage Rating - DC":"125 V","Current Rating (Amps)":"750 mA","Operating Temperature":"-55°C~125°C","Breaking Capacity @ Rated Voltage":"50A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.4600","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/604a0e4c498aa97d2607992508357d04.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What approvals does 0451.750NRL carry?","answer":"The 0451.750NRL is approved by CSA and UL, covering North American regulatory requirements for equipment-level circuit protection."},{"question":"What is the melting I²t of 0451.750NRL?","answer":"The melting I²t is 0.185, which defines the energy threshold for the fuse element to open — useful for coordinating with downstream components during surge events."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/littelfuse-inc/0451.750NRL","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/littelfuse-inc/0451.750NRL when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:49:49.435Z","lastPublished":"2026-08-11T15:49:49.435Z","indexable":true}}