{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH2122-2XF40-2LA2","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH2122-2XF40-2LA2","canonicalUrl":"https://aoctrl.com/siemens/3RH2122-2XF40-2LA2","factsUrl":"https://aoctrl.com/api/mcp/products/3RH2122-2XF40-2LA2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS contactor relay for railway applications, 3RH2122-2XF40-2LA2, S00 size, 72–125 VDC coil, 2 NO instantaneous contacts, varistor surge suppressor, screw and snap-on mounting on 35 mm DIN rail.","salesMarkdown":"## Railway-rated contactor relay, S00 frame The Siemens SIRIUS 3RH2122-2XF40-2LA2 is a contactor relay designated for railway applications, built on the S00 contactor size platform. It carries 2 instantaneous NO contacts and a varistor surge suppressor built into the coil circuit. The rated control voltage spans 72 to 125 VDC, with a holding current mean value of 7 mA and an inrush current peak of 1.1 A. Pick-up time at DC is 25 to 45 ms; arcing time runs 10 to 15 ms. Mounting position allows hanging or horizontal surface mounting. Side-by-side mounting is permitted. Overall dimensions: 73 mm deep, 45 mm wide, 70 mm high. ## Switching capacity across voltage ranges Rated operational current varies by voltage level: 10 A at 24 V, 4.7 A at 60 V, 3 A at 110 V, 1.2 A at 220 V, 10 A at 230 V, 3 A at 400 V, 0.5 A at 440 V, 2 A at 500 V, 0.26 A at 600 V, and 1 A at 690 V. The 10 A rating at both 24 V and 230 V suggests the contacts are rated for both low-voltage DC and standard AC line voltages — common in railway auxiliary circuits where both battery and mains supplies are present. Relative humidity minimum 10%. The substance prohibitance date of 10/01/2009 aligns with RoHS compliance deadlines. Mechanical endurance: 30,000,000 operating cycles typical for the contactor.","metaTitle":"Siemens 3RH2122-2XF40-2LA2 SIRIUS Contactor Relay, 72–125 VD","metaDescription":"Siemens SIRIUS 3RH2122-2XF40-2LA2 contactor relay for railway applications. 72–125 VDC coil, 2 NO contacts, varistor surge suppression. S00 size, 45 mm wide. Current production. So","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","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","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":"hanging, 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","at AWG cables for auxiliary contacts":"2x (20 ... 12)","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","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,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/90c3f7040a3663b62eabc90e7e237470.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=1109097&mlfb=3RH2122-2XF40-2LA2","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RH2122-2XF40-2LA2/alternatives.json"},"ai":{"faq":[{"question":"What is the coil voltage for 3RH2122-2XF40-2LA2?","answer":"Rated control voltage is 72 to 125 VDC. Holding current mean value is 7 mA; inrush current peak is 1.1 A."},{"question":"Will 3RH2122-2XF40-2LA2 drop into a panel specified around 3RH2122-1BW40?","answer":"Both are S00-size SIRIUS contactor relays with the same 45 mm width and DIN-rail mounting footprint. The 2XF40-2LA2 variant adds the varistor surge suppressor and the 72–125 VDC coil range. Mechanical fit should be identical, but verify the coil voltage matches your control circuit — the 1BW40 may have a different coil rating."},{"question":"What compliance documentation does Siemens provide for this part?","answer":"The substance prohibitance date of 10/01/2009 indicates RoHS compliance. Siemens typically provides CE, UKCA, and EAC declarations for SIRIUS contactor relays. Specific certification documents should be requested at time of order."},{"question":"Where can I buy 3RH2122-2XF40-2LA2?","answer":"Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH2122-2XF40-2LA2","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/3RH2122-2XF40-2LA2 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}}