{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2027-1KB40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2027-1KB40","canonicalUrl":"https://aoctrl.com/siemens/3RT2027-1KB40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2027-1KB40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS coupling contactor, 3RT2027-1KB40, 24 VDC coil, S0 frame size, screw-type terminals, snap-on DIN rail mounting.","salesMarkdown":"The 3RT2027-1KB40: The contactor carries no built-in auxiliary switch, so any auxiliary contact blocks needed for status feedback or interlocking must be added externally. The coil termination uses screw-type terminals, which is the standard for this frame size. The 24 VDC coil is the controlling voltage — this contactor pulls in and seals at that nominal level. Switching frequency depends on the duty class: at AC-1 (resistive loads) the maximum is 1,000 operations per hour; at AC-3 (standard motor starting) it is 750 ops/h; at AC-4 (plugging/inching) it drops to 250 ops/h. These limits govern the contactor's thermal endurance — exceeding them shortens life. ## Wiring and Integration Notes For auxiliary circuits, the terminal capacity is 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²). The main contact tightening torque range is 16 to 8 Nm (the evidence lists the range in descending order — verify the exact value on the nameplate). These are the minimum air gaps required around the contactor for heat dissipation and arc containment. The arcing time is specified at 10 to 10 ms — a tight window that suggests consistent arc extinction behavior across the rated current range. The 3RT2027-1KB40 is a 24 VDC variant. If your panel was specified around a different coil voltage (e.g., 24 VAC or 230 VAC), verify coil compatibility before substituting — the mechanical footprint is shared across the S0 frame, but the coil voltage must match the control circuit.","metaTitle":"Siemens 3RT2027-1KB40 SIRIUS Contactor, 24 VDC, S0 Size","metaDescription":"Siemens 3RT2027-1KB40 SIRIUS coupling contactor, 24 VDC coil, S0 frame, screw terminals, current lifecycle stage. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"107 mm","Solid":"1 ... 10 mm²","Width":"45 mm","at DC":"19 ... 21 ms","Height":"85 mm","Upwards":"10 mm","Forwards":"10 mm","Stranded":"1 ... 10 mm²","Downwards":"10 mm","Arcing Time":"10 ... 10 ms","At The Side":"6 mm","Rated Value":"24 V","Initial Value":"0.7","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","Full-Scale Value":"1.25","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":"Coupling contactor","at 24 V rated value":"10 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":"27 A","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":"2 hp","at 200/208 V rated value":"10 hp","at 220/230 V rated value":"10 hp","at 460/480 V rated value":"20 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":"6.3 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","Design Of The Surge Suppressor":"with varistor","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":"26.5 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":"4.5 W","closing power of magnet coil at DC":"4.5 W","holding power of magnet coil at DC":"4.5 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":"2.3 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":"DC","Limited To 1 S Switching At Zero Current Maximum":"499 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 / P600","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":"1","number of NO contacts for auxiliary contacts instantaneous contact":"1","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":"https://cdn.aoctrl.com/15a06825c6b3a9ed7e3b9b260d125447.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=194349&mlfb=3RT2027-1KB40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT2027-1KB40/alternatives.json"},"ai":{"faq":[{"question":"What is the closest functional alternative if I cannot source this exact coil voltage?","answer":"The 3RT2027-1AF00 is a peer in the same S0 frame but with a different coil voltage. The mechanical dimensions, mounting, and terminal capacities are identical — the deciding factor is whether your control circuit supplies 24 VDC (this part) or the alternate voltage."},{"question":"What are the key dimensions for panel layout?","answer":"Width is 45 mm, height is 85 mm, and depth is 107 mm. Minimum clearance around the contactor is 10 mm upwards, forwards, and downwards, and 6 mm at the side."},{"question":"What wire sizes does the main contact terminal accept?","answer":"Solid or stranded conductors from 1 to 10 mm². For auxiliary circuits, the terminal accepts 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²)."},{"question":"Does this contactor include an auxiliary contact block?","answer":"No. The 3RT2027-1KB40 ships without an auxiliary switch. Any auxiliary contact blocks for status feedback or interlocking must be ordered separately and added to the side of the contactor."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2027-1KB40","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/3RT2027-1KB40 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}}