{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA2318-8XB30-1FB4","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA2318-8XB30-1FB4","canonicalUrl":"https://aoctrl.com/siemens/3RA2318-8XB30-1FB4","factsUrl":"https://aoctrl.com/api/mcp/products/3RA2318-8XB30-1FB4","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RA2318-8XB30-1FB4 reversing contactor assembly, size S00, 7.5 kW at 400 V AC-3, 24 V DC coil, screw terminals, diode surge suppressor, DIN rail mount.","salesMarkdown":"## What this reversing assembly delivers The 3RA2318-8XB30-1FB4: This is a Siemens SIRIUS reversing contactor assembly — two 3RT2018-1FB42 contactors mechanically interlocked in a single housing, so you get forward-reverse control without wiring your own interlock and risking a phase-to-phase short during a midnight startup. Coil is 24 V DC with a built-in diode surge suppressor — no external flyback diode needed on the PLC output. The coil terminals are screw-type, same as the main circuit, so one tool handles the whole assembly. ## Mounting and panel fit Size S00 frame, 90 mm wide by 68 mm tall by 73 mm deep — it screws or snaps onto 35 mm DIN rail. Clearance around the assembly: 6 mm upwards, forwards, downwards, and to the side — zero mm backwards. That tight rear clearance means it sits close to the backplane, so plan the wiring duct depth accordingly. ## Wiring terminals and conductor sizes That covers most motor feeds up to 4 mm² without needing ferrules on stranded wire. The supplied RH assembly kit (3RA2913-2AA1) is included — that's the mechanical interlock bracket and shaft that ties the two contactors together so only one can close at a time. ## Operating conditions and life The mechanical life of the contactor is 10 million operations typical — that's the relay, not the assembly, but it's the wear item you'll replace first. Vibration resistance: 11.4 g for 5 ms and 7.3 g for 10 ms on both AC and DC — that's the shock rating, not continuous vibration. For continuous vibration environments, check the mounting rail damping. ## Sourcing and compliance RoHS compliance date is 10/01/2009 — it meets the original RoHS directive.","metaTitle":"Siemens 3RA2318-8XB30-1FB4 SIRIUS Reversing Contactor","metaDescription":"Siemens 3RA2318-8XB30-1FB4 SIRIUS reversing contactor assembly, size S00, 7.5 kW at 400 V. Active production, sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Motor Starters"],"specifications":{"Depth":"73 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), 2x 4 mm²","Width":"90 mm","at AC":"11,4g / 5 ms, 7,3g / 10 ms","at DC":"11,4g / 5 ms, 7,3g / 10 ms","Height":"68 mm","Upwards":"6 mm","Forwards":"6 mm","Backwards":"0 mm","Downwards":"6 mm","At The Side":"6 mm","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Screw-type terminals","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Fastening Method":"screw and snap-on mounting onto 35 mm standard mounting rail","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":"S00","Solid Or Stranded":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","at DC rated value":"24 V","Product Brand Name":"SIRIUS","Product Designation":"Reversing contactor assembly","Of Contactor Typical":"10 000 000","at 400 V rated value":"7.5 kW","at 480 V rated value":"14 A","at 500 V rated value":"7.5 kW","at 600 V rated value":"11 A","at 690 V rated value":"7.5 kW","For Main Current Circuit":"screw-type terminals","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","1 Of The Supplied Contactor":"3RT2018-1FB42","2 Of The Supplied Contactor":"3RT2018-1FB42","at AC-4 at 400 V rated value":"5.5 kW","Substance Prohibitance (Date)":"10/01/2009","Design Of The Surge Suppressor":"diode","at AWG cables for main contacts":"2x (20 ... 16), 2x (18 ... 14)","of the supplied RH assembly kit":"3RA2913-2AA1","For Auxiliary And Control Circuit":"screw-type terminals","Product Extension Auxiliary Switch":"Yes","Product Function Bus Communication":"Yes","With Type Of Assignment 2 Required":"gG NH 3NA, DIAZED 5SB, NEOZED 5SE: 25 A","closing power of magnet coil at DC":"4 W","holding power of magnet coil at DC":"4 W","At Contactor For Auxiliary Contacts":"Screw-type terminals","operating frequency at AC-3 maximum":"750 1/h","With Type Of Coordination 1 Required":"gG NH 3NA, DIAZED 5SB, NEOZED 5SE: 50 A","at AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14)","number of NC contacts for main contacts":"0","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), 2x (0.75 ... 2.5 mm²)","Number Of Poles For Main Current Circuit":"3","Contact Reliability Of Auxiliary Contacts":"< 1 error per 100 million operating cycles","with low demand rate according to SN 31920":"40 %","protocol is supported AS-Interface protocol":"No","with high demand rate according to SN 31920":"75 %","Type Of Voltage Of The Control Supply Voltage":"DC","operating voltage at AC-3 rated value maximum":"690 V","contact rating of auxiliary contacts according to UL":"A600 / Q600","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","product function control circuit interface with IO link":"No","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gG: 10 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/080f944f58213ff8d1975c1291f089b2.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=449570&mlfb=3RA2318-8XB30-1FB4","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RA2318-8XB30-1FB4/alternatives.json"},"ai":{"faq":[{"question":"What is the 3RA2318-8XB30-1FB4 rated for at 400 V and 480 V?","answer":"At 400 V AC-3 duty it is rated 7.5 kW. At 480 V the rated current is 14 A, which corresponds to 10 hp at 460/480 V. For AC-4 (heavy jogging/reversing) at 400 V, the rating drops to 5.5 kW."},{"question":"What contactors are supplied inside the 3RA2318-8XB30-1FB4 assembly?","answer":"The assembly contains two Siemens 3RT2018-1FB42 contactors, mechanically interlocked by the included 3RA2913-2AA1 RH assembly kit. The coil is 24 V DC with a built-in diode suppressor."},{"question":"What are the wiring terminal sizes for the 3RA2318-8XB30-1FB4?","answer":"AWG equivalents are 2x (20...16) and 2x (18...14). Coil terminals are also screw-type."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA2318-8XB30-1FB4","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/3RA2318-8XB30-1FB4 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}}