{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RV2021-4EA20","brand":"Siemens","brandSlug":"siemens","productSlug":"3RV2021-4EA20","canonicalUrl":"https://aoctrl.com/siemens/3RV2021-4EA20","factsUrl":"https://aoctrl.com/api/mcp/products/3RV2021-4EA20","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RV2021-4EA20 motor protection circuit breaker, Class 10 trip, 25 kA breaking capacity at 400 V, phase failure detection, spring-loaded terminals.","salesMarkdown":"## Trip Class 10 and motor protection The 3RV2021-4EA20 is a Class 10 motor protection circuit breaker — it trips within 10 seconds at 7.2× the thermal setting, matching the startup profile of standard AC induction motors without nuisance tripping on inrush. This is the difference between a breaker that protects the motor and one that just clears a fault. Rated for motor protection, not just cable protection — the thermal-magnetic curve is shaped for the motor's overload region, not the feeder's short-circuit withstand. At 400 V, the 3RV2021-4EA20 interrupts 25 kA. At 690 V, that drops to 2 kA — the arc extinction voltage limits the high-voltage performance. For 480 V systems, the rated short-circuit breaking capacity is 32 A, which is the continuous current at that voltage, not the interrupt rating. The backup fuse requirement at 400 V is gL/gG 63 A — the fuse clears faults above the breaker's interrupt limit, letting you size the breaker for the motor and the fuse for the fault energy. At 240 V, the breaking capacity is 100 kA — this is typical for the SIRIUS line, giving headroom on low-voltage distribution panels where the transformer fault current can be high. ## Wiring and integration Spring-loaded terminals accept 2x 1–10 mm² solid or stranded — no screw torque, no loose connections on a hot panel. The push-in entry works with ferruled wire; the spring cage holds the full cross-section. Mounting position any — vertical, horizontal, or inverted, the thermal trip curve does not shift.","metaTitle":"Siemens 3RV2021-4EA20 SIRIUS Motor Protection Circuit","metaDescription":"Siemens 3RV2021-4EA20 SIRIUS MPCB, Class 10, 25 kA at 400 V, phase failure detection, spring terminals. Current production. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Motor Protection Circuit Breakers (MPCB)"],"specifications":{"Depth":"97 mm","Width":"45 mm","title":"3RV2021-4EA20","Height":"119 mm","Upwards":"50 mm","Forwards":"0 mm","at 400 V":"gL/gG 63 A","at 500 V":"gL/gG 63 A","at 690 V":"gL/gG 63 A","Backwards":"0 mm","Downwards":"50 mm","Trip Class":"CLASS 10","At The Side":"30 mm","Rated Value":"20 ... 690 V","description":"Circuit breaker size S0 for motor protection, CLASS 10 A-release 27...32 A N-release 400 A Spring-type terminal Standard switching capacity","During Storage":"-50 ... +80 °C","at AC-3 maximum":"15 1/h","lifecycle_stage":"current","During Operation":"-20 ... +60 °C","During Transport":"-50 ... +80 °C","Fastening Method":"screw and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715","at AC-3e maximum":"15 1/h","Mounting Position":"any","Solid Or Stranded":"2x (1 ... 10 mm²)","Product Brand Name":"SIRIUS","Product Designation":"Circuit breaker","at 230 V rated value":"5 hp","at 240 V rated value":"100 kA","at 400 V rated value":"25 kA","at 480 V rated value":"32 A","at 500 V rated value":"5 kA","at 600 V rated value":"32 A","at 690 V rated value":"2 kA","Design Of The Product":"For motor protection","Ground Fault Detection":"No","Phase Failure Detection":"Yes","For Main Current Circuit":"spring-loaded terminals","at 110/120 V rated value":"2 hp","at 200/208 V rated value":"7.5 hp","at 220/230 V rated value":"10 hp","at 460/480 V rated value":"20 hp","at AC at 240 V rated value":"100 kA","at AC at 400 V rated value":"55 kA","at AC at 500 V rated value":"10 kA","at AC at 690 V rated value":"4 kA","Design Of Screwdriver Shaft":"Diameter 3 mm","Size Of The Circuit-Breaker":"S0","Size Of The Screwdriver Tip":"3,0 x 0,5 mm","at AC-3 rated value maximum":"690 V","Of The Main Contacts Typical":"100 000","at AC in hot operating state":"13.25 W","at AC-3 at 400 V rated value":"32 A","at AC-3e rated value maximum":"690 V","Of Auxiliary Contacts Typical":"100 000","Substance Prohibitance (Date)":"10/01/2009","at AC-3e at 400 V rated value":"32 A","Design Of The Overload Release":"thermal","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"32 A","Design Of The Short-Circuit Trip":"magnetic","for AWG cables for main contacts":"2x (18 ... 8)","Product Extension Auxiliary Switch":"Yes","Relative Humidity During Operation":"10 ... 95 %","Display Version For Switching Status":"Handle","Surge Voltage Resistance Rated Value":"6 kV","at AC in hot operating state per pole":"4.4 W","With Side-By-Side Mounting At The Side":"0 mm","reference code according to IEC 81346-2":"Q","Finely Stranded With Core End Processing":"2x (1 ... 6 mm²)","Number Of Poles For Main Current Circuit":"3","Product Function Short Circuit Protection":"Yes","with low demand rate according to SN 31920":"50 FIT","Finely Stranded Without Core End Processing":"2x (1 ... 6 mm²)","with high demand rate according to SN 31920":"50 %","number of CO contacts for auxiliary contacts":"0","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"0","shock resistance according to IEC 60068-2-27":"25g / 11 ms","Electrical Endurance (Operating Cycles) Typical":"100 000","Size Of Contactor Can Be Combined Company-Specific":"S00, S0","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Arrangement Of Electrical Connectors For Main Current Circuit":"Top and bottom","Response Value Current Of Instantaneous Short-Circuit Trip Unit":"400 A","insulation voltage with degree of pollution 3 at AC rated value":"690 V","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"27 ... 32 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$184.89","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/69e3aae776a3a972c11948ccacc118a3.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=527178&mlfb=3RV2021-4EA20"},"ai":{"faq":[{"question":"What size wire fits the 3RV2021-4EA20 spring terminal?","answer":"The spring terminals accept 2x 1 to 10 mm² solid or stranded wire. Ferruled conductors work with the push-in entry."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RV2021-4EA20","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/3RV2021-4EA20 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}