{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2518-2XF40-0LA2","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2518-2XF40-0LA2","canonicalUrl":"https://aoctrl.com/siemens/3RT2518-2XF40-0LA2","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2518-2XF40-0LA2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT2518-2XF40-0LA2 power contactor, size S00, DC coil 72-125 V, spring-type terminals, 45 mm width, 73 mm depth, 70 mm height, screw and snap-on 35 mm DIN rail mounting.","salesMarkdown":"## DC coil 72-125 V — pull-in margin and transformer loading The 3RT2518-2XF40-0LA2: The DC coil is rated for 72 to 125 V DC. The pull-in voltage is 0.7 × rated value, so at a nominal 110 V DC bus the contactor pulls in reliably at 77 V — well within the typical battery sag during a station black-start sequence. The inrush current peak is 1.1 A; that spike loads the control transformer and the rectifier — if you are feeding multiple contactors from a common DC supply, sum the inrush peaks and check the transformer's regulation curve so the bus does not dip below the hold-in threshold. Hold-in power is lower than pull-in — the 0.7 factor applies to the initial pull-in only. Once sealed, the coil current drops to the holding value, which keeps the temperature rise inside the S00 envelope manageable even in a crowded 45 mm slot. ## Switching capacity — AC motor and DC load break For AC motor duty, the contactor is rated 2 hp at 230 V, 14 A at 480 V, and 11 A at 600 V. That derating is typical for DC arcs — the arcing time is 10-15 ms, and the DC arc extinguishes only when the current falls below the minimum arc current, so the contact gap and blowout design limit the DC rating. The main contacts are rated 20-12 A. This is the continuous thermal current (Ith) — the contactor can carry that current continuously in free air. In a sealed panel with multiple contactors side by side, derate per the manufacturer's grouping factor; the 45 mm width leaves little space for natural convection between units. ## Spring terminals and wire range — panel wiring speed The coil and auxiliary connections use spring-type terminals. The solid conductor range is 2×(0.5-1.5 mm²), 2×(0.75-2.5 mm²), and 2×4 mm². The main power terminals accept 2×(0.5-4 mm²) solid or stranded. Spring terminals eliminate the need for a screwdriver torque check — push the ferrule in until the cage clicks. For the 4 mm² power wires, use a ferrule sized for the strand class; the spring force is sufficient for Class 2 stranded but may not grip Class 5 flexible without a ferrule. ## Mounting and clearance — DIN rail and enclosure fit The height is 70 mm — check the DIN rail end-stop height if the rail is near the top of the enclosure.","metaTitle":"Siemens 3RT2518-2XF40-0LA2 SIRIUS Contactor","metaDescription":"Siemens 3RT2518-2XF40-0LA2 SIRIUS power contactor, size S00, DC coil 72-125 V, spring terminals, 45 mm wide. Active production, sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"73 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), 2x 4 mm²","Width":"45 mm","at DC":"25 ... 45 ms","Height":"70 mm","Upwards":"10 mm","Forwards":"10 mm","Downwards":"10 mm","Arcing Time":"10 ... 15 ms","At The Side":"6 mm","Rated Value":"72 ... 125 V","Initial Value":"0.7","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Spring-type terminals","Type Of Voltage":"DC","at AC-4 maximum":"250 1/h","lifecycle_stage":"current","Auxiliary Switch":"Yes","During Operation":"-40 ... +70 °C","Fastening Method":"screw and snap-on mounting onto 35 mm DIN rail according to DIN EN 50022","Full-Scale Value":"1.25","For Main Contacts":"20 ... 12","Mounting Position":"+/-180° rotation possible on vertical mounting surface, can be tilted forward and backward by +/- 22.5° on vertical mounting surface, standing, on horizontal mounting surface","Size Of Contactor":"S00","Solid Or Stranded":"2x (0,5 ... 4 mm²)","Product Brand Name":"SIRIUS","Inrush Current Peak":"1.1 A","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":"30 000 000","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":"2 hp","at 400 V rated value":"3 A","at 480 V rated value":"14 A","at 500 V rated value":"2 A","at 600 V rated value":"11 A","at 690 V rated value":"1 A","Design Of The Product":"With extended operating range","Instantaneous Contact":"0","Side-By-Side Mounting":"Yes","For Auxiliary Contacts":"20 ... 12","For Main Current Circuit":"spring-loaded terminals","at 110/120 V rated value":"1 hp","at 200/208 V rated value":"3 hp","at 220/230 V rated value":"5 hp","at 460/480 V rated value":"10 hp","at 575/600 V rated value":"10 hp","Locked-Rotor Current Peak":"0.04 A","Relative Humidity Minimum":"10 %","Holding Current Mean Value":"7 mA","Of Main Circuit Rated Value":"6 kV","at AC-3 rated value maximum":"400 V","at maximum AC-1 rated value":"4 mm²","at AC-2 at 400 V rated value":"7.5 kW","at AC-4 at 400 V rated value":"11.5 A","Substance Prohibitance (Date)":"10/01/2009","Design Of The Surge Suppressor":"with varistor","Duration Of Inrush Current Peak":"50 µs","Locked-Rotor Current Mean Value":"0.04 A","at AWG cables for main contacts":"2x (20 ... 12)","Duration Of Locked-Rotor Current":"250 ms","Of Auxiliary Circuit Rated Value":"6 kV","For Auxiliary And Control Circuit":"spring-loaded terminals","Function Module For Communication":"No","Product Function Bus Communication":"No","With Type Of Assignment 2 Required":"gG NH 3NA, DIAZED 5SB, NEOZED 5SE: 20 A","closing power of magnet coil at DC":"4.5 W","holding power of magnet coil at DC":"0.75 W","At Contactor For Auxiliary Contacts":"Spring-type terminals","With Type Of Coordination 1 Required":"gG NH 3NA, DIAZED 5SB, NEOZED 5SE: 35 A","at AWG cables for auxiliary contacts":"2x (20 ... 12)","operational current at AC-12 maximum":"10 A","number of NC contacts for main contacts":"2","number of NO contacts for main contacts":"2","reference code according to IEC 81346-2":"Q","Finely Stranded With Core End Processing":"2x (0.5 ... 2.5 mm²)","Number Of Poles For Main Current Circuit":"4","Product Function Short Circuit Protection":"No","mirror contact according to IEC 60947-4-1":"Yes","Finely Stranded Without Core End Processing":"2x (0.5 ... 2.5 mm²)","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"0","Type Of Voltage Of The Control Supply Voltage":"DC","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)","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/f7786552ec3c49e8abb73468eb640dc7.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=1029402&mlfb=3RT2518-2XF40-0LA2","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT2518-2XF40-0LA2/alternatives.json"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2518-2XF40-0LA2","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/3RT2518-2XF40-0LA2 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}}