{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2027-2KG40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2027-2KG40","canonicalUrl":"https://aoctrl.com/siemens/3RT2027-2KG40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2027-2KG40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT2027-2KG40, size S0 coupling contactor, spring-type terminals, 24 V DC coil rated 10 A, 45 mm wide, current lifecycle.","salesMarkdown":"## Coupling contactor for signal isolation It carries a 24 V DC coil rated at 10 A, meaning it can switch a substantial inductive load on the control side without overloading the PLC card. Spring-type terminals (cage clamp) accept solid or stranded wire from 1 to 10 mm², and dual-wire entry handles 2x (0.5 to 2.5 mm²) for daisy-chaining. No auxiliary switch is built in — plan for an external auxiliary contact block if feedback is needed. ## Switching capacity across voltages Rated for resistive and motor loads across common control voltages: 48 V at 2 A, 60 V at 2 A, 110 V at 1 A, 125 V at 0.9 A, 220 V at 0.3 A, and 400 V at 3 A. At 230 V it carries a 5 hp motor load — a common rating for small pump or fan starters. ## Mechanical and thermal limits Maximum switching frequency depends on duty: 1000 cycles/hour for AC-1 (resistive), 750 for AC-2 and AC-3 (motor starting/running), 250 for AC-4 (plugging/inching). ## DIN rail integration and clearances Dimensions: 45 mm wide, 102 mm high, 107 mm deep — fits a standard S0 footprint. Main contacts are 18 to 8 AWG rated. The spring terminals reduce wiring time and resist vibration loosening in transport or high-vibration panels.","metaTitle":"Siemens SIRIUS 3RT2027-2KG40 Coupling Contactor, S0 Size, 24","metaDescription":"Siemens 3RT2027-2KG40 SIRIUS coupling contactor, size S0, spring-type terminals, 24V DC coil rated 10A. Current lifecycle stage. Available to order via 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":"102 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":"125 V","Initial Value":"0.7","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","Full-Scale Value":"1.25","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":"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":"spring-loaded 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-2 at 400 V rated value":"15 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","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":"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":"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":"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":"2.3 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":"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/2f87bf68439831c79190602a25412388.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=468190&mlfb=3RT2027-2KG40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT2027-2KG40/alternatives.json"},"ai":{"faq":[{"question":"What does the coupling contactor do differently from a standard contactor?","answer":"A coupling contactor is designed for signal isolation — it sits between a control output (like a PLC) and a power contactor coil, providing galvanic separation and preventing back-EMF from damaging the control card. The 3RT2027-2KG40 does not include auxiliary contacts, so it is purely a coupling relay."},{"question":"Where can I buy 3RT2027-2KG40?","answer":"This part is sourced to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm commitment."},{"question":"What wire sizes fit the spring terminals?","answer":"Solid or stranded wire from 1 to 10 mm², and dual-wire entry accepts 2x (0.5 to 2.5 mm²) for looping through."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2027-2KG40","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/3RT2027-2KG40 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}}