{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH2122-2XF40-0LB2","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH2122-2XF40-0LB2","canonicalUrl":"https://aoctrl.com/siemens/3RH2122-2XF40-0LB2","factsUrl":"https://aoctrl.com/api/mcp/products/3RH2122-2XF40-0LB2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RH2122-2XF40-0LB2 contactor relay for railway applications, Size S00, coil 72-125 V DC, varistor surge suppressor, 2 instantaneous contacts, screw and snap-on mounting on 35 mm DIN rail.","salesMarkdown":"## Integrator note — railway contactor relay The Siemens SIRIUS 3RH2122-2XF40-0LB2 is a contactor relay designed for railway applications. Coil rated 72-125 V DC with a varistor surge suppressor built in — that varistor clamps the coil's turn-off spike, so no external free-wheel diode needed on the DC rail. Holding current averages 7 mA; inrush peak hits 1.1 A. Two instantaneous contacts handle the switching. ## Mounting and fit Size S00 body: 73 mm deep, 45 mm wide, 70 mm tall. ## Switching performance and ratings Arcing time 10-15 ms; DC switching times 25-45 ms. Contact ratings across the voltage range: 10 A at 24 V DC, 4.7 A at 60 V DC, 3 A at 110 V DC, 1.2 A at 220 V DC, 10 A at 230 V AC, 3 A at 400 V AC, 0.5 A at 440 V AC, 2 A at 500 V AC, 0.26 A at 600 V AC, 1 A at 690 V AC. Mechanical life typical 30 million operations. Lifecycle stage is current. Substance prohibitance date 10/01/2009. Relative humidity minimum 10 %.","metaTitle":"Siemens SIRIUS 3RH2122-2XF40-0LB2 Contactor Relay, 72-125 V","metaDescription":"Siemens SIRIUS 3RH2122-2XF40-0LB2 contactor relay for railway applications. Coil 72-125 V DC, varistor suppressor, 2 NO/NC, screw & snap-on DIN rail. Quoted on request.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"73 mm","Width":"45 mm","at DC":"25 ... 45 ms","title":"3RH2122-2XF40-0LB2","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","description":"Contactor relay for railway 2 NO + 2 NC, 72-125 V DC, 0.7... 1.25*US, with integrated varistor Size S00, spring-type terminal suitable for PLC outputs","Initial Value":"0.7","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-40 ... +70 °C","Fastening Method":"screw and snap-on mounting onto 35 mm DIN rail","Full-Scale Value":"1.25","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":"Contactor relay for railway applications","at 24 V rated value":"10 A","at 60 V rated value":"4.7 A","Of Contactor Typical":"30 000 000","at 110 V rated value":"3 A","at 220 V rated value":"1.2 A","at 230 V rated value":"10 A","at 400 V rated value":"3 A","at 440 V rated value":"0.5 A","at 500 V rated value":"2 A","at 600 V rated value":"0.26 A","at 690 V rated value":"1 A","Instantaneous Contact":"2","Side-By-Side Mounting":"Yes","Locked-Rotor Current Peak":"0.04 A","Relative Humidity Minimum":"10 %","Holding Current Mean Value":"7 mA","Substance Prohibitance (Date)":"10/01/2009","Design Of The Surge Suppressor":"Varistor","Duration Of Inrush Current Peak":"50 µs","Locked-Rotor Current Mean Value":"0.04 A","Duration Of Locked-Rotor Current":"250 ms","Product Extension Auxiliary Switch":"Yes","closing power of magnet coil at DC":"4.5 W","holding power of magnet coil at DC":"0.75 W","Surge Voltage Resistance Rated Value":"6 kV","operating frequency at DC-12 maximum":"1 000 1/h","operating frequency at DC-13 maximum":"1 000 1/h","operational current at AC-12 maximum":"10 A","for AWG cables for auxiliary contacts":"2x (20 ... 12)","reference code according to IEC 81346-2":"K","Finely Stranded With Core End Processing":"2x (0.5 ... 2.5 mm²)","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","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 %","number of NC contacts for auxiliary contacts":"2","number of NO contacts for auxiliary contacts":"2","Type Of Voltage Of The Control Supply Voltage":"DC","contact rating of auxiliary contacts according to UL":"A600 / Q600","Identification Number And Letter For Switching Elements":"22 E","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","Type Of Electrical Connection For Auxiliary And Control Circuit":"spring-loaded terminals","insulation voltage with degree of pollution 3 at AC rated value":"690 V","AWG number as coded connectable conductor cross section for auxiliary contacts":"20 ... 12","Of The Contactor With Added Electronically Optimized Auxiliary Switch Block Typical":"5 000 000","Design Of The Fuse Link For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gL/gG: 10 A","residual current of the electronics for control with signal <0> at DC at 24 V maximum permissible":"10 mA","design of the miniature circuit breaker for short-circuit protection of the auxiliary circuit up to 230 V":"C characteristic: 6 A; 0.4 kA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/b589c1c1b3caa07ca1aa49307712d75f.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=1130227&mlfb=3RH2122-2XF40-0LB2"},"ai":{"faq":[{"question":"What is the closest functional second-source — 3RH2122-1BW40?","answer":"The 3RH2122-1BW40 is a peer in the same SIRIUS contactor relay family, but the 2XF40-0LB2 carries a 72-125 V DC coil with a varistor suppressor, while the 1BW40 may differ in coil voltage and suppressor type. Verify coil compatibility before substitution."},{"question":"Will 3RH2122-2XF40-0LB2 drop into a panel specified around 3RH2122-1BW40 without rewiring?","answer":"Both share the same SIRIUS S00 footprint and DIN-rail mounting, so mechanical fit is identical. Electrical fit depends on coil voltage and suppressor — the 2XF40-0LB2 uses a 72-125 V DC coil with varistor; if the 1BW40 has a different coil rating, rewiring may be needed."},{"question":"What compliance documentation does this brand provide?","answer":"The part carries a substance prohibitance date of 10/01/2009, indicating RoHS compliance. Standard Siemens SIRIUS documentation includes CE and UL declarations — request the specific certificate with your RFQ."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH2122-2XF40-0LB2","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/3RH2122-2XF40-0LB2 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}