{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2028-2AV04","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2028-2AV04","canonicalUrl":"https://aoctrl.com/siemens/3RT2028-2AV04","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2028-2AV04","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, Size S0, 3RT2028-2AV04, 34 A at 480 V AC-3, spring-type terminals, screw and snap-on 35 mm DIN rail mount.","salesMarkdown":"## SIRIUS power contactor, Size S0 — 34 A at 480 V AC-3 The Siemens 3RT2028-2AV04 is a SIRIUS power contactor in the Size S0 frame, rated for 34 A at 480 V in AC-3 duty — the standard motor-switching category per IEC 60947-4-1. That 34 A figure governs the maximum full-load current of a three-phase induction motor it can switch under normal starting and running conditions; for a 480 V supply, that typically covers motors up to about 25 hp, though the exact horsepower depends on the motor's full-load amps and service factor. The contactor carries a 5 hp rating at 230 V, confirming its suitability for smaller motors on lower voltages as well. Spring-type terminals on the magnet coil and main contact wiring rated for solid or stranded conductors from 1 to 10 mm², with auxiliary contacts accepting 2x (0.5 to 2.5 mm²). The contactor mounts via screw and snap-on onto 35 mm DIN rail per DIN EN 60715, and the mounting position allows ±180° rotation on a vertical surface plus ±22.5° tilt forward/backward — useful when panel layout forces an unconventional orientation. ## Switching frequency and duty-cycle limits The contactor's maximum switching frequency depends on the utilization category: 1,000 operations per hour in AC-1 (resistive loads), 750 per hour in AC-2 and AC-3 (motor starting and running), and 250 per hour in AC-4 (plugging or inching duty) (–,). AC-4 is the most severe — each operation involves making and breaking locked-rotor current — so the lower limit reflects the thermal stress on the contacts. For a motor circuit running at AC-3, the 750 ops/h ceiling is rarely a constraint in normal process control; it becomes relevant only in high-cycle applications like indexing conveyors or rapid reversing. ## DC switching ratings and auxiliary contact configuration The contactor carries DC switching ratings across a range of voltages: 6 A at 24 V, 2 A at 48 V and 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, and 3 A at 400 V (–,). These are the maximum currents the main contacts can break in a DC circuit at the stated voltage — DC arcs are harder to extinguish than AC, so the ratings drop sharply as voltage rises. The auxiliary contact block is not factory-fitted (shows 18 to 8 auxiliary contacts, likely a range for field-installable add-on blocks; the base unit ships without auxiliary switches. Plan to order a separate auxiliary contact block if the application needs feedback or interlocking. ## Environmental limits and mechanical endurance Dimensions: 102 mm height, 45 mm width, 144 mm depth.","metaTitle":"Siemens 3RT2028-2AV04 SIRIUS Power Contactor, 34 A at 480 V,","metaDescription":"Siemens 3RT2028-2AV04 SIRIUS power contactor, Size S0 frame, rated 34 A at 480 V AC-3. Spring-type terminals, screw and snap-on DIN rail mount. Current lifecycle stage; available t","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"144 mm","Solid":"1 ... 10 mm²","Width":"45 mm","at AC":"4 ... 16 ms","Height":"102 mm","Upwards":"10 mm","Forwards":"10 mm","Stranded":"1 ... 10 mm²","at 50 Hz":"0.25","Downwards":"10 mm","Arcing Time":"10 ... 10 ms","At The Side":"6 mm","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Spring-type terminals","at AC-1 maximum":"1 000 1/h","at AC-2 maximum":"750 1/h","at AC-3 maximum":"750 1/h","at AC-4 maximum":"250 1/h","lifecycle_stage":"current","Auxiliary Switch":"No","During Operation":"-25 ... +60 °C","Fastening Method":"screw and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715","at AC-3e maximum":"750 1/h","For Main Contacts":"18 ... 8","Mounting Position":"+/-180° rotation possible on vertical mounting surface; can be tilted forward and backward by +/- 22.5° on vertical mounting surface","Size Of Contactor":"S0","Solid Or Stranded":"2x (0.5 ... 2.5 mm²)","Product Brand Name":"SIRIUS","Product Designation":"Power contactor","at 24 V rated value":"6 A","at 48 V rated value":"2 A","at 60 V rated value":"2 A","Of Contactor Typical":"10 000 000","at 110 V rated value":"1 A","at 125 V rated value":"0.9 A","at 220 V rated value":"0.3 A","at 230 V rated value":"5 hp","at 400 V rated value":"3 A","at 440 V rated value":"0.6 A","at 480 V rated value":"34 A","at 50 Hz rated value":"400 V","at 500 V rated value":"2 A","at 600 V rated value":"27 A","at 690 V rated value":"1 A","Side-By-Side Mounting":"Yes","For Auxiliary Contacts":"20 ... 14","For Main Current Circuit":"spring-loaded terminals","at 110/120 V rated value":"3 hp","at 200/208 V rated value":"10 hp","at 220/230 V rated value":"10 hp","at 460/480 V rated value":"25 hp","at 575/600 V rated value":"25 hp","Relative Humidity Minimum":"10 %","Of Main Circuit Rated Value":"6 kV","at AC-3 rated value maximum":"690 V","at AC in hot operating state":"9.6 W","at AC-2 at 400 V rated value":"18.5 kW","at AC-3e rated value maximum":"690 V","at AC-4 at 400 V rated value":"22 A","safety-related switching OFF":"Yes","Substance Prohibitance (Date)":"10/01/2009","Of Auxiliary Circuit Rated Value":"6 kV","at AC-5a up to 690 V rated value":"44 A","at AC-5b up to 400 V rated value":"31.5 A","For Auxiliary And Control Circuit":"spring-loaded terminals","Function Module For Communication":"No","With Type Of Assignment 2 Required":"gG: 50A (690V,100kA), aM: 25A (690V, 100kA), BS88: 50A (415V, 80kA)","Without Load Current Share Typical":"9.8 W","At Contactor For Auxiliary Contacts":"Spring-type terminals","With Type Of Coordination 1 Required":"gG: 125A (690V,100kA), aM: 50A (690V,100kA), BS88: 125A (415V,80kA)","operational current at AC-12 maximum":"10 A","at AC in hot operating state per pole":"3.2 W","for AWG cables for auxiliary contacts":"2x (20 ... 14)","number of NO contacts for main contacts":"3","reference code according to IEC 81346-2":"Q","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 mm²)","Number Of Poles For Main Current Circuit":"3","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","mirror contact according to IEC 60947-4-1":"Yes","with low demand rate according to SN 31920":"40 %","Finely Stranded Without Core End Processing":"2x (0.5 ... 2.5 mm²)","with high demand rate according to SN 31920":"73 %","Type Of Voltage Of The Control Supply Voltage":"AC","Limited To 1 S Switching At Zero Current Maximum":"593 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 5 S Switching At Zero Current Maximum":"341 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 10 S Switching At Zero Current Maximum":"260 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 30 S Switching At Zero Current Maximum":"199 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 60 S Switching At Zero Current Maximum":"162 A; Use minimum cross-section acc. to AC-1 rated value","contact rating of auxiliary contacts according to UL":"A600 / Q600","Of Main Circuit With Degree Of Pollution 3 Rated Value":"690 V","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","Of Auxiliary Circuit With Degree Of Pollution 3 Rated Value":"690 V","For Short-Circuit Protection Of The Auxiliary Switch Required":"gG: 10 A (500 V, 1 kA)","minimum cross-section in main circuit at maximum AC-1 rated value":"10 mm²","number of NC contacts for auxiliary contacts instantaneous contact":"2","number of NO contacts for auxiliary contacts instantaneous contact":"2","Of The Contactor With Added Electronically Optimized Auxiliary Switch Block Typical":"5 000 000"}},"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=258172&mlfb=3RT2028-2AV04","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT2028-2AV04/alternatives.json"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2028-2AV04","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/3RT2028-2AV04 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}}