{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2028-1AP04-ZX95","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2028-1AP04-ZX95","canonicalUrl":"https://aoctrl.com/siemens/3RT2028-1AP04-ZX95","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2028-1AP04-ZX95","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT2028-1AP04-ZX95 power contactor, size S0, 3-pole, 34 A at 480 V AC-3, 45 mm width, 141 mm depth, screw and snap-on mounting onto 35 mm DIN rail per EN 60715.","salesMarkdown":"## Panel Fit and Mounting Constraints The 3RT2028-1AP04-ZX95 is a size S0 power contactor with a width of 45 mm and a depth of 141 mm — the depth is the dimension that dictates enclosure selection, especially in shallow backpanels or retrofit cabinets where gland-plate clearance is tight. Mounting is via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, with the mounting position allowing +/-180° rotation on a vertical surface and +/-22.5° tilt forward/backward, so it can be oriented to fit cable entry paths without violating the clearance zones. Minimum air and creepage clearances are specified: 10 mm upwards, 10 mm forwards, 10 mm downwards, and 6 mm at the side — these must be maintained to the enclosure wall or adjacent components to avoid arc flash or tracking under fault. ## Rated Motor Current and Duty Cycles Rated at 34 A at 480 V in AC-3 duty (the standard motor-switching category for squirrel-cage motors), this contactor handles typical North American 480 V three-phase motor loads up to that current — which corresponds to roughly a 20–25 hp motor depending on full-load amps. Maximum switching frequency varies by duty: 1000 operations per hour in AC-1 (resistive), 750/h in AC-2 and AC-3, and 250/h in AC-4 (plugging/inching) — so for high-cycle applications like conveyor indexing or compressor cycling, stay within the AC-3 ceiling of 750 ops/h to avoid contact wear. The contactor's mechanical life is rated at 10 million operations typical, with an arcing time of 10 ms at 50 Hz — this is the contact separation interval during which the arc extinguishes; the 4–16 ms AC arcing window covers variations in load power factor and supply voltage. ## Wire Termination and Auxiliary Contact Provisions Main contact terminations accept solid or stranded wire from 1 to 10 mm² (roughly 18 to 8 AWG), and the magnet coil uses screw-type terminals — no special crimp tooling is required for field wiring, but torque settings should follow the Siemens installation instructions to avoid terminal damage. Auxiliary switch blocks are not included as standard (the base contactor has no auxiliary contacts), so if the application requires feedback or interlocking, a separate auxiliary contact block must be ordered and snapped onto the contactor's side or front — the S0 frame supports Siemens auxiliary switch modules.","metaTitle":"Siemens 3RT2028-1AP04-ZX95 SIRIUS Power Contactor","metaDescription":"Siemens 3RT2028-1AP04-ZX95 SIRIUS power contactor, size S0, rated 34 A at 480 V AC-3. 45 mm wide, 141 mm deep, screw/snap-on DIN rail mount.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"141 mm","Solid":"1 ... 10 mm²","Width":"45 mm","at AC":"4 ... 16 ms","title":"3RT2028-1AP04-ZX95","Height":"85 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","description":"CONTACTOR, AC-3, 18.5KW/400V, 2NO+2NC, AC 230V 50HZ, 3-POLE, SZ S0 SCREW TERMINAL REMOVABLE AUX. SWITCH PACKAGE = 48 UNITS","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Screw-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":"16 ... 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 ... 1.5 mm²), 2x (0.75 ... 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":"230 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":"screw-type 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-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":"screw-type 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":"Screw-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 ... 16), 2x (18 ... 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), 2x (0.75 ... 2.5 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 %","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","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","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,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/12709f985feffd68e917b6a852a4dcd1.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=382816&mlfb=3RT2028-1AP04-ZX95"},"ai":{"faq":[{"question":"What is the rated motor current for 3RT2028-1AP04-ZX95 at 480 V?","answer":"It is rated 34 A at 480 V in AC-3 duty, which is the standard category for switching squirrel-cage induction motors. This corresponds to a motor size of roughly 20–25 hp at 480 V, depending on the motor's full-load current."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2028-1AP04-ZX95","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/3RT2028-1AP04-ZX95 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:47:38.189Z","lastPublished":"2026-07-22T19:47:38.189Z","indexable":true}}