{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2018-1UB42","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2018-1UB42","canonicalUrl":"https://aoctrl.com/siemens/3RT2018-1UB42","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2018-1UB42","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, 3RT2018-1UB42, Size S00, 24 VDC coil, screw-type terminals, 45 mm width, current lifecycle stage.","salesMarkdown":"The coil is rated 24 VDC. That's the nominal pull-in voltage; the dropout band sits at 7 to 13 ms, which matters if you're coordinating with a PLC output that needs to drop the contactor quickly on a safety stop. Main contact ratings are given per duty. At 230 V it handles 2 hp; at 400 V the current rating is 3 A. For DC switching, the auxiliary contacts break 10 A at 24 V, 2 A at 48 V, 2 A at 60 V, 1 A at 110 V, 0.9 A at 125 V, and 0.3 A at 220 V. So the DC curve drops fast above 60 V — if you're switching a 125 VDC solenoid bank, you're limited to 0.9 A per contact. Mechanical life is typical at 30,000,000 operations. The maximum switching frequency varies by duty: 1,000 1/h under AC-1 (resistive), 750 1/h under AC-2 and AC-3 (motor start/run), and 250 1/h under AC-4 (plugging/inching). AC-3e also maxes at 750 1/h. If your application cycles a conveyor motor at 500 starts per hour, the AC-3 rating has headroom. The contactor measures 45 mm wide, 58 mm high, and 73 mm deep. For multiple conductors, it takes 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or 2x 4 mm². That covers most control-circuit wiring gauges you'd run in a panel.","metaTitle":"Siemens 3RT2018-1UB42 SIRIUS Power Contactor, 24 VDC, Size S","metaDescription":"Siemens 3RT2018-1UB42 SIRIUS power contactor, 24 VDC coil, Size S00, 45 mm width, screw terminals, current lifecycle stage, available to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"73 mm","Solid":"0.5 ... 4 mm²","Width":"45 mm","at DC":"7 ... 13 ms","Height":"58 mm","Upwards":"10 mm","Forwards":"10 mm","Stranded":"0.5 ... 4 mm²","Downwards":"10 mm","Arcing Time":"10 ... 15 ms","At The Side":"6 mm","Rated Value":"24 V","Initial Value":"0.8","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Screw-type terminals","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","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","Size Of Contactor":"S00","Solid Or Stranded":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), 2x 4 mm²","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":"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 440 V rated value":"0.2 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","Side-By-Side Mounting":"Yes","For Auxiliary Contacts":"20 ... 12","For Main Current Circuit":"screw-type 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","Relative Humidity Minimum":"10 %","Of Main Circuit Rated Value":"6 kV","Safety-Related Switching On":"Yes","at AC-3 rated value maximum":"690 V","at AC in hot operating state":"3 W","at AC-2 at 400 V rated value":"7.5 kW","at AC-3e rated value maximum":"690 V","at AC-4 at 400 V rated value":"11.5 A","safety-related switching OFF":"Yes","Substance Prohibitance (Date)":"10/01/2009","Design Of The Surge Suppressor":"with varistor","Of Auxiliary Circuit Rated Value":"6 kV","at AC-5a up to 690 V rated value":"19.4 A","at AC-5b up to 400 V rated value":"13.2 A","For Auxiliary And Control Circuit":"screw-type terminals","Function Module For Communication":"No","With Type Of Assignment 2 Required":"gG: 25A (690V,100kA), aM: 20A (690V,100kA), BS88: 25A (415V,80kA)","Without Load Current Share Typical":"4 W","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","With Type Of Coordination 1 Required":"gG: 50A (690V,100kA), aM: 25A (690V,100kA), BS88: 50A (415V,80kA)","operational current at AC-12 maximum":"10 A","at AC in hot operating state per pole":"1 W","for AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14), 2x 12","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 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":"300 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 5 S Switching At Zero Current Maximum":"169 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 10 S Switching At Zero Current Maximum":"128 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 30 S Switching At Zero Current Maximum":"92 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 60 S Switching At Zero Current Maximum":"74 A; Use minimum cross-section acc. to AC-1 rated value","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)","minimum cross-section in main circuit at maximum AC-1 rated value":"4 mm²","number of NC 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":"https://cdn.aoctrl.com/6cb9bd832029dc8f73020b686d9c3f16.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=1097094&mlfb=3RT2018-1UB42","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT2018-1UB42/alternatives.json"},"ai":{"faq":[{"question":"How do I get current pricing and availability for 3RT2018-1UB42?","answer":"Submit an RFQ through the storefront; availability and current pricing are confirmed at quote time through independent distribution channels."},{"question":"What is 3RT2018-1UB42's listed depth?","answer":"The depth is 73 mm, with a width of 45 mm and height of 58 mm."},{"question":"What wire sizes does 3RT2018-1UB42 accept?","answer":"Solid and stranded wire from 0.5 to 4 mm², with multiple-conductor combinations up to 2x 4 mm²."},{"question":"Will 3RT2018-1UB42 drop into a panel specified around 3RT2015-1BW42 without rewiring?","answer":"Both are Size S00 contactors on a 45 mm footprint with screw terminals, so they share the same DIN-rail slot and terminal spacing. The main difference is the coil voltage — the 3RT2015-1BW42 uses a 24 VAC coil, while this one is 24 VDC. Verify the control supply before swapping."},{"question":"What compliance documentation does Siemens provide for 3RT2018-1UB42?","answer":"Standard Siemens SIRIUS documentation includes the declaration of conformity for the Low Voltage Directive and EMC Directive. RoHS and REACH compliance statements are available in the product's CE declaration. UL and CSA file numbers are listed on the nameplate and in the datasheet."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2018-1UB42","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/3RT2018-1UB42 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}}