{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1647-1AL21","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1647-1AL21","canonicalUrl":"https://aoctrl.com/siemens/3RT1647-1AL21","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1647-1AL21","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT1647-1AL21 capacitor contactor, AC-6 duty, 50 kVAr / 400 V, 230 V AC 50/60 Hz coil, 3-pole, Size S3, screw terminals, DIN rail mount.","salesMarkdown":"The Siemens 3RT1647-1AL21 is a 3-pole capacitor contactor in the S3 frame, designed specifically for switching power-factor-correction capacitor banks under AC-6 duty. Its headline rating is 50 kVAr at 400 V — that's the reactive power it can switch without exceeding the capacitor inrush current limits. The 230 V AC coil pulls from a standard control transformer at 50/60 Hz. This is a phased-out product. The official Siemens successor is the 3RT2636-1AL23. The 90 A at AC-1 at 400 V rating tells you the contactor's thermal current capacity for resistive loads — it's the ceiling for the main poles. For capacitor switching (AC-6), the relevant figure is the 50 kVAr at 400 V; that's the bank size this contactor is designed to switch, with the series resistors or reactors handling the initial surge. The 3-pole set (3 NO main contacts) handles three-phase banks. One auxiliary NO contact is built in for status feedback or interlocking. The IP00 body (IP20 on the front with a cover or box terminal) means it's intended for enclosure mounting — the panel provides the environmental seal. The S3 frame dimensions (167 x 70 x 183 mm) fit the standard S3 footprint — check your panel depth against the 183 mm projection. The manufacturer lists this as a phased-out product. The preferred successor is the 3RT2636-1AL23. No last-time-buy window is stated, so availability is confirmed per inquiry. RoHS compliance date is noted as 05/01/2012, meaning the part meets the EU RoHS substance restrictions from that date forward.","metaTitle":"Siemens 3RT1647-1AL21 Capacitor Contactor, 50 kVAr / 400 V,","metaDescription":"Siemens 3RT1647-1AL21 capacitor contactor, AC-6 rated 50 kVAr at 400 V, 230 V AC 50/60 Hz coil, 3-pole S3 frame. Phased-out; successor 3RT2636-1AL23. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"183 mm","Width":"70 mm","Height":"167 mm","On The Front":"IP00; IP20 on the front with cover / box terminal","Of The Terminal":"IP00","Type Of Voltage":"AC","lifecycle_stage":"current","Fastening Method":"screw and snap-on mounting onto 35 mm standard mounting rail according to DIN EN 50022","protection class IP":"IP00","at 50 Hz rated value":"230 ... 230 V","at 60 Hz rated value":"230 ... 230 V","Side-By-Side Mounting":"Yes","For Main Current Circuit":"screw-type terminals","at AC-1 at 400 V rated value":"90 A","Substance Prohibitance (Date)":"05/01/2012","For Auxiliary And Control Circuit":"screw-type terminals","Ambient Temperature During Operation":"-25 ... +60 °C","number of NC contacts for main contacts":"0","number of NO contacts for main contacts":"3","reference code according to IEC 81346-2":"Q","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"1","Identification Number And Letter For Switching Elements":"1","Supply Voltage Frequency For Auxiliary And Control Circuit Rated Value":"50 ... 60 Hz"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=92887&mlfb=3RT1647-1AL21","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1647-1AL21/alternatives.json"},"ai":{"faq":[{"question":"What is the 3RT1647-1AL21 used for?","answer":"It is a capacitor contactor for switching power-factor-correction capacitor banks. Its AC-6 rating of 50 kVAr at 400 V means it is sized for three-phase capacitor banks up to that reactive power, with the appropriate series impedance to limit inrush current."},{"question":"What are the key dimensions of the 3RT1647-1AL21?","answer":"Height 167 mm, width 70 mm, depth 183 mm. It mounts on 35 mm DIN rail per DIN EN 50022 and can be mounted side-by-side without spacing."},{"question":"Where can I buy the 3RT1647-1AL21?","answer":"This phased-out part is sourced to order through independent industrial distribution. Submit an RFQ for current availability and pricing — we confirm both at quote time."},{"question":"Does the 3RT1647-1AL21 drop into a panel designed for the 3RT1044-1FB46?","answer":"Both are S3 frame contactors with the same 70 mm width and screw-type main terminals, so the DIN rail footprint and wiring space are compatible. The 3RT1647-1AL21 is 183 mm deep versus 201 mm for the 3RT1044-1FB46, so it actually needs less enclosure depth. Verify the auxiliary contact configuration — the 3RT1647-1AL21 has 1 NO auxiliary contact, while the 3RT1044-1FB46 has 2 NO + 2 NC."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1647-1AL21","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/3RT1647-1AL21 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}}