{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RB2055-1FC2","brand":"Siemens","brandSlug":"siemens","productSlug":"3RB2055-1FC2","canonicalUrl":"https://aoctrl.com/siemens/3RB2055-1FC2","factsUrl":"https://aoctrl.com/api/mcp/products/3RB2055-1FC2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS solid-state overload relay, 3RB2055-1FC2, CLASS 10E trip, 3-pole, ATEX Ex II (2) GD, contactor mounting or stand-alone installation, depth 155 mm.","salesMarkdown":"The Siemens 3RB2055-1FC2 is a SIRIUS solid-state overload relay — a three-pole device that protects motor circuits against overload and phase imbalance by monitoring current and tripping within the CLASS 10E curve (typically 10 seconds at 7.2× Ie). It can be mounted directly onto a contactor or installed stand-alone in a panel, giving flexibility in cabinet layout. The solid-state design means no heating elements to drift or replace; power dissipation per pole is only 0.02 W (0.05 W total for the main circuit), so it doesn't add significant heat inside the enclosure. Terminals accept solid conductors from 0.5 to 4 mm² (or 2× 0.5 to 2.5 mm²) and finely stranded with ferrules from 0.5 to 2.5 mm² (2× 0.5 to 1.5 mm²) — covers most control wiring gauges used in motor starter circuits. Dimensions are 120 mm wide, 119 mm high, 155 mm deep — fits standard 120 mm-wide DIN-rail or contactor-mounting footprints. Side clearance of 6 mm is required for ventilation; no clearance needed above, below, or behind the unit. The relay is rated for operation at altitudes up to 2 000 m without derating, and can operate in ambient temperatures from -25 to +60 °C with 100 % relative humidity — suitable for most indoor industrial environments.","metaTitle":"Siemens 3RB2055-1FC2 SIRIUS solid-state overload relay, CLAS","metaDescription":"Siemens 3RB2055-1FC2 SIRIUS solid-state overload relay, CLASS 10E trip, 3-pole, ATEX Ex II (2) GD, contactor mounting or stand-alone. Depth 155 mm. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"Depth":"155 mm","Solid":"0.5 ... 4 mm², 2x (0.5 ... 2.5 mm²)","Width":"120 mm","Height":"119 mm","Maximum":"2 000 m","Upwards":"0 mm","at 24 V":"2 A","at 60 V":"0.55 A","Forwards":"0 mm","at 110 V":"0.3 A","at 120 V":"4 A","at 125 V":"0.3 A","at 220 V":"0.11 A","at 230 V":"3 A","Backwards":"0 mm","Downwards":"0 mm","Trip class":"CLASS 10E","At The Side":"6 mm","On The Front":"IP00","Mounting type":"Contactor mounting/stand-alone installation","During Storage":"-40 ... +80 °C","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","During Transport":"-40 ... +80 °C","Shock resistance":"15g / 11 ms","Mounting position":"any","Product brand name":"SIRIUS","Type of protection":"PTB 06 ATEX 3001 Ex II (2) GD","Product designation":"solid-state overload relay","For Auxiliary Contacts":"0","For Main Current Circuit":"busbar connection","at AC-3 rated value maximum":"1 000 V","at AC in hot operating state":"0.05 W","Relative humidity during operation":"100 %","due to burst acc. to IEC 61000-4-4":"2 kV (power ports), 1 kV (signal ports) corresponds to degree of severity 3","Surge voltage resistance rated value":"8 kV","Reference code acc. to DIN EN 81346-2":"F","at AC in hot operating state per pole":"0.02 W","Finely Stranded With Core End Processing":"0.5 ... 2.5 mm², 2x (0.5 ... 1.5 mm²)","Number of poles for main current circuit":"3","at AWG conductors for auxiliary contacts":"2x (20 ... 14)","For Auxiliary And Control Current Circuit":"screw-type terminals","Number of NC contacts for auxiliary contacts":"1","Number of NO contacts for auxiliary contacts":"1","with degree of pollution 3 at AC rated value":"1 000 V","Electrostatic discharge acc. to IEC 61000-4-2":"6 kV contact discharge / 8 kV air discharge","Size of contactor can be combined company-specific":"S6","due to conductor-earth surge acc. to IEC 61000-4-5":"2 kV (line to earth) corresponds to degree of severity 3","Removable Terminal For Auxiliary And Control Circuit":"Yes","For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gL/gG: 6 A","Adjustable pick-up value current of the current-dependent overload release":"50 ... 200 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=427779&mlfb=3RB2055-1FC2","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RB2055-1FC2/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy the 3RB2055-1FC2 and get a price?","answer":"The part is sourced and quoted to order against an RFQ through independent distribution; availability and current pricing are confirmed at quote time."},{"question":"What is the trip class of the 3RB2055-1FC2?","answer":"The trip class is CLASS 10E, meaning it trips within 10 seconds at 7.2× the full-load current setting."},{"question":"Does the 3RB2055-1FC2 have ATEX approval?","answer":"Yes, it carries ATEX certification PTB 06 ATEX 3001 Ex II (2) GD for use in potentially explosive atmospheres."},{"question":"What are the mounting options for the 3RB2055-1FC2?","answer":"It can be mounted directly onto a contactor or installed stand-alone in a panel; mounting position is any orientation."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RB2055-1FC2","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/3RB2055-1FC2 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}}