{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2026-4BB40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2026-4BB40","canonicalUrl":"https://aoctrl.com/siemens/3RT2026-4BB40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2026-4BB40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, 3RT2026-4BB40, S0 size, 24 VDC coil, screw and snap-on DIN rail mount, 10 A at 24 VDC.","salesMarkdown":"## What It Is & Where It Goes It's the workhorse for switching motor loads, resistive heaters, and other inductive or resistive circuits inside a control panel. The S0 size is the compact footprint in the SIRIUS family — 45 mm wide, 85 mm tall, 107 mm deep — so it fits standard 35 mm DIN rail (DIN EN 60715) with either screw-fixed or snap-on mounting. ## Coil & Control Circuit The coil is rated at 24 VDC nominal. At that rated voltage, the contactor can switch 10 A on the main contacts. The coil connection uses a ring cable lug, which is a solid, vibration-resistant termination — good for panels that see transport or machine vibration. That's fast enough for most sequencing and interlocking schemes. ## Switching Capacity & Duty Cycles The contactor is rated for different switching frequencies depending on the load category. For AC-1 (resistive loads), it can handle up to 1,000 operations per hour. For AC-3 (squirrel-cage motor starting) and AC-2 (slip-ring motor starting), it's rated at 750 ops/h. For AC-4 (plugging, inching, reversing), the rate drops to 250 ops/h — that's the heavy-duty cycle where the contacts take more wear. The mechanical life is typical for the class at 10 million operations, so the limiting factor is electrical wear under load, not the mechanism. ## Environmental & Clearance These matter for heat dissipation and arc flash containment — don't crowd the contactor below those numbers, especially in a high-duty-cycle application. ## Auxiliary Contacts The contactor comes with an integrated auxiliary switch. That's a standard feature on this variant — you don't need to order a separate side-mount block for basic status feedback or interlocking. The auxiliary contacts are rated for various DC voltages: 2 A at 48 V, 2 A at 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, 0.6 A at 440 V, and 2 A at 500 V. For AC motor control at 480 V, the auxiliary is rated at 21 A; at 600 V, it's 22 A. That's enough for pilot duty on most PLC inputs or relay coils.","metaTitle":"Siemens 3RT2026-4BB40 SIRIUS Power Contactor, 24 VDC Coil, S","metaDescription":"Siemens 3RT2026-4BB40 SIRIUS power contactor, S0 size, 24 VDC coil with ring cable lug connection. Rated for 10 A at 24 VDC. Screw and snap-on DIN rail mount. Active production. So","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"107 mm","Width":"45 mm","at DC":"15 ... 18 ms","Height":"85 mm","Upwards":"10 mm","Forwards":"10 mm","Downwards":"10 mm","Arcing Time":"10 ... 10 ms","At The Side":"6 mm","Rated Value":"24 V","Initial Value":"0.8","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Ring cable lug connection","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":"Yes","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":"1.1","at AC-3e maximum":"750 1/h","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","Product Brand Name":"SIRIUS","Product Designation":"Power 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":"3 hp","at 400 V rated value":"3 A","at 440 V rated value":"0.6 A","at 480 V rated value":"21 A","at 500 V rated value":"2 A","at 600 V rated value":"22 A","at 690 V rated value":"1 A","Side-By-Side Mounting":"Yes","For Main Current Circuit":"Ring cable lug connection","at 110/120 V rated value":"2 hp","at 200/208 V rated value":"5 hp","at 220/230 V rated value":"7.5 hp","at 460/480 V rated value":"15 hp","at 575/600 V rated value":"20 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":"5.7 W","at AC-3e rated value maximum":"690 V","at AC-4 at 400 V rated value":"15.5 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":"35.2 A","at AC-5b up to 400 V rated value":"20.7 A","For Auxiliary And Control Circuit":"ring terminal lug connection","Function Module For Communication":"No","With Type Of Assignment 2 Required":"gG: 35A (690V, 100kA), aM: 20A (690V, 100kA), BS88: 35A (415V, 80kA)","Without Load Current Share Typical":"5.9 W","closing power of magnet coil at DC":"5.9 W","holding power of magnet coil at DC":"5.9 W","At Contactor For Auxiliary Contacts":"Ring cable lug connection","With Type Of Coordination 1 Required":"gG: 100 A (690 V, 100 kA), aM: 50 A (690 V, 100 kA), BS88: 100 A (415 V, 80 kA)","operational current at AC-12 maximum":"10 A","at AC in hot operating state per pole":"1.9 W","number of NO contacts for main contacts":"3","reference code according to IEC 81346-2":"Q","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":"375 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 5 S Switching At Zero Current Maximum":"300 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 10 S Switching At Zero Current Maximum":"210 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 30 S Switching At Zero Current Maximum":"144 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 60 S Switching At Zero Current Maximum":"118 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":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=524074&mlfb=3RT2026-4BB40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT2026-4BB40/alternatives.json"},"ai":{"faq":[{"question":"What are the key dimensions for panel layout?","answer":"The S0 frame size measures 45 mm wide, 85 mm tall, and 107 mm deep. It mounts on 35 mm DIN rail per DIN EN 60715. Minimum clearance around the contactor is 10 mm upwards, forwards, and downwards, and 6 mm to the side."},{"question":"What is the coil voltage and connection type?","answer":"The coil is 24 VDC nominal. The connection is via a ring cable lug, which provides a secure, vibration-resistant termination. At rated voltage, the main contacts are rated for 10 A."},{"question":"Does this contactor include auxiliary contacts?","answer":"Yes, it has an integrated auxiliary switch. The auxiliary contacts are rated for various DC voltages up to 2 A at 48/60 V, and for AC motor control up to 22 A at 600 V."},{"question":"What switching frequencies can this contactor handle?","answer":"For AC-1 resistive loads, up to 1,000 operations per hour. For AC-2 and AC-3 motor loads, 750 ops/h. For AC-4 heavy-duty reversing/plugging, 250 ops/h. Mechanical life is 10 million operations."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2026-4BB40","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/3RT2026-4BB40 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}}