{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA1120-4BC26-0BB4","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA1120-4BC26-0BB4","canonicalUrl":"https://aoctrl.com/siemens/3RA1120-4BC26-0BB4","factsUrl":"https://aoctrl.com/api/mcp/products/3RA1120-4BC26-0BB4","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS non-fused load feeder, size S0, direct starter, 7.5 kW at 400 V, 24 V DC coil, bimetal overload, snap-on 40 mm busbar, IP20.","salesMarkdown":"## What This Load Feeder Delivers The Siemens 3RA1120-4BC26-0BB4 is a SIRIUS non-fused load feeder — a pre-assembled direct starter combining a circuit-breaker, contactor, and bimetal overload relay in one size S0 housing. The 24 V DC coil matches standard PLC control voltages; the 45 mm width and 154 mm depth let it fit a 45 mm busbar center-to-center spacing on a 40 mm system. ## Wiring and Mounting — Panel Fit Snaps directly onto 40 mm busbar systems via the supplied busbar adapter 8US1051-5DM07. The 45 mm width and 183 mm height clear standard enclosure gland plates; clearance needs: 30 mm upward, 10 mm forward, 9 mm backward, 0 mm downward. Accepts solid or stranded copper from 1 to 6 mm², and can double up two conductors per terminal (2x 1–2.5 mm² or 2x 2.5–6 mm²). AWG equivalents: 2x 14–10 AWG on main contacts. IP20 front protection keeps fingers out; pollution degree 3 suits industrial control panels. ## Built-In Components and Protection Factory-integrated with a circuit-breaker 3RV1021-4BA10 for short-circuit and overload protection, a contactor 3RT1026-1BB40 for switching, and a link module 3RA1921-1BA00. Motor protection is bimetal type — thermal curve matched to the motor's heating characteristic. Rated insulation voltage 690 V, shock resistance 12.5g, ambient operating range -20 to +70 °C, storage -55 to +80 °C. No PROFINET or PROFIBUS DP onboard; this is a hardwired starter slice.","metaTitle":"Siemens 3RA1120-4BC26-0BB4 SIRIUS Load Feeder","metaDescription":"Siemens 3RA1120-4BC26-0BB4 SIRIUS non-fused load feeder, 7.5 kW at 400 V, size S0 direct starter with bimetal protection.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"Depth":"154 mm","Solid":"1 ... 6 mm², 2x (1 ... 2.5 mm²), 2x (2.5 ... 6 mm²)","Width":"45 mm","Height":"183 mm","Upwards":"30 mm","Forwards":"10 mm","Stranded":"1 ... 6 mm²","Backwards":"9 mm","Downwards":"0 mm","At The Side":"30 mm","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-20 ... +70 °C","Fastening Method":"for snapping onto 40 mm busbar systems","Shock Resistance":"12.5g","Mounting Position":"with vertical mounting surface +/-90° rotatable, with vertical mounting surface +/- 22.5° tiltable to the front and back","PROFINET protocol":"No","Solid Or Stranded":"1 ... 6 mm²","at DC rated value":"24 V","Product Brand Name":"SIRIUS","Type Of Assignment":"2","Degree Of Pollution":"3","Product Designation":"non-fused load feeder","Size Of Load Feeder":"S0","PROFIBUS DP protocol":"No","at 400 V rated value":"7.5 kW","Design Of The Product":"direct starter","Number Of Digital Inputs":"0","Of The Supplied Contactor":"3RT1026-1BB40","NO-Load Switching Frequency":"15 1/s","Of The Supplied Link Module":"3RA1921-1BA00","Type Of The Motor Protection":"bimetal","Substance Prohibitance (Date)":"05/01/2012","Insulation Voltage Rated Value":"690 V","Of The Supplied Busbar Adapter":"8US1051-5DM07","Busbar Center-To-Center Spacing":"40 mm","Design Of The Switching Contact":"electromechanical","at AWG cables for main contacts":"2x (14 ... 10)","Of The Supplied Circuit-Breakers":"3RV1021-4BA10","protection class IP on the front":"IP20","Design Of Short-Circuit Protection":"circuit-breakers","Product Extension Auxiliary Switch":"Yes","Product Function Bus Communication":"No","Surge Voltage Resistance Rated Value":"6 kV","With Side-By-Side Mounting At The Side":"0 mm","reference code according to IEC 81346-2":"Q","Finely Stranded With Core End Processing":"1 ... 6 mm²","Number Of Poles For Main Current Circuit":"3","Product Function Short Circuit Protection":"Yes","protocol is supported AS-Interface protocol":"No","number of CO contacts for auxiliary contacts":"0","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"0","Type Of Voltage Of The Control Supply Voltage":"DC","operating voltage at AC-3 rated value maximum":"400 V","operational current at AC-3 at 400 V rated value":"15.5 A","Type Of Electrical Connection For Main Current Circuit":"screw-type terminals","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Mechanical Service Life (Switching Cycles) Of Contactor Typical":"10 000 000","AWG number as coded connectable conductor cross section for main contacts":"14 ... 10","breaking capacity maximum short-circuit current (Icu) at 400 V rated value":"50 kA","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"14 ... 20 A"}},"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=46964&mlfb=3RA1120-4BC26-0BB4","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RA1120-4BC26-0BB4/alternatives.json"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA1120-4BC26-0BB4","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/3RA1120-4BC26-0BB4 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}}