{"product_id":"siemens-3tk2821-1cb30-safety-relay","title":"SIEMENS 3TK2821-1CB30 Safety Relay 24V AC\/DC 3NO 1NC","description":"\u003cstyle\u003e.nxs-industrial-product-page{--industrial-navy:#082f49;--industrial-blue:#0b4f7c;--industrial-blue-2:#0f6ea8;--industrial-blue-3:#1784c1;--industrial-cyan:#38bdf8;--steel-blue:#dcebf5;--steel-blue-2:#edf6fb;--steel-line:#c9dce9;--surface:#ffffff;--surface-soft:#f7fbfe;--text-main:#173042;--text-muted:#5e7382;--shadow-soft:0 10px 30px rgba(8,47,73,0.08);--shadow-hover:0 16px 36px rgba(8,79,124,0.15);--radius-lg:14px;--radius-md:10px;}.nxs-industrial-product-page,.nxs-industrial-product-page *{margin:0;padding:0;box-sizing:border-box;font-family:Arial,Helvetica,sans-serif;}.nxs-industrial-product-page{background-color:#f3f8fb;background-image:linear-gradient(180deg,#eef6fb 0,#f7fafc 320px,#eef3f7 100%),linear-gradient(rgba(15,110,168,0.025) 1px,transparent 1px),linear-gradient(90deg,rgba(15,110,168,0.025) 1px,transparent 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*,.nxs-industrial-product-page *::before,.nxs-industrial-product-page *::after{transition:none !important;}}\u003c\/style\u003e\u003cdiv class=\"nxs-industrial-product-page\"\u003e\u003cdiv class=\"container\"\u003e\u003cmain\u003e\u003csection class=\"section\"\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003ctable class=\"spec-table\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eSIEMENS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel Number\u003c\/td\u003e\n\u003ctd\u003e3TK2821-1CB30\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Category\u003c\/td\u003e\n\u003ctd\u003eSafety Relay\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Family\u003c\/td\u003e\n\u003ctd\u003eSIRIUS 3TK28\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRated Control Supply Voltage\u003c\/td\u003e\n\u003ctd\u003e24 V AC\/DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTerminal Type\u003c\/td\u003e\n\u003ctd\u003eScrew-Type\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWidth\u003c\/td\u003e\n\u003ctd\u003e22.5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSafety Output Circuits\u003c\/td\u003e\n\u003ctd\u003e3 NO\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSignaling Circuit\u003c\/td\u003e\n\u003ctd\u003e1 NC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput Terminals\u003c\/td\u003e\n\u003ctd\u003e13\/14, 23\/24, 33\/34\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSignaling Terminals\u003c\/td\u003e\n\u003ctd\u003e41\/42\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReset \/ Feedback Circuit\u003c\/td\u003e\n\u003ctd\u003eY1\/Y2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/section\u003e\u003csection class=\"section\"\u003e\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cdiv class=\"features\"\u003e\n\u003carticle class=\"card\"\u003e\u003ch3\u003e24 V AC\/DC Supply\u003c\/h3\u003e\n\u003cp\u003eThe SIRIUS 3TK2821-1CB30 safety relay is designed for a 24 V AC\/DC control supply.\u003c\/p\u003e\u003c\/article\u003e\u003carticle class=\"card\"\u003e\u003ch3\u003e3 NO Safety Outputs\u003c\/h3\u003e\n\u003cp\u003eThree normally open output circuits are provided at terminals 13\/14, 23\/24 and 33\/34.\u003c\/p\u003e\u003c\/article\u003e\u003carticle class=\"card\"\u003e\u003ch3\u003e1 NC Signaling Circuit\u003c\/h3\u003e\n\u003cp\u003eA normally closed signaling circuit is provided at terminals 41\/42.\u003c\/p\u003e\u003c\/article\u003e\u003carticle class=\"card\"\u003e\u003ch3\u003eScrew-Type Terminals\u003c\/h3\u003e\n\u003cp\u003eThis 3TK2821 configuration uses screw-type terminals for electrical connections.\u003c\/p\u003e\u003c\/article\u003e\u003carticle class=\"card\"\u003e\u003ch3\u003e22.5 mm Device Width\u003c\/h3\u003e\n\u003cp\u003eThe safety relay uses a 22.5 mm wide housing format for control cabinet applications.\u003c\/p\u003e\u003c\/article\u003e\u003carticle class=\"card\"\u003e\u003ch3\u003eReset and Feedback Circuit\u003c\/h3\u003e\n\u003cp\u003eTerminals Y1\/Y2 are documented for reset button and feedback circuit functions.\u003c\/p\u003e\u003c\/article\u003e\n\u003c\/div\u003e\u003c\/section\u003e\u003csection class=\"section\"\u003e\u003ch2\u003eApplications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eIndustrial safety circuits\u003c\/li\u003e\n\u003cli\u003eMachine safety control systems\u003c\/li\u003e\n\u003cli\u003eSafety-related relay circuits\u003c\/li\u003e\n\u003cli\u003eControl cabinet safety circuits\u003c\/li\u003e\n\u003cli\u003eSafety contact expansion\u003c\/li\u003e\n\u003cli\u003eIndustrial machinery safety functions\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/section\u003e\u003csection class=\"section\"\u003e\u003ch2\u003ePurchase Information\u003c\/h2\u003e\n\u003cp\u003eWe support online purchase of the SIEMENS 3TK2821-1CB30 Safety Relay. If you need to make bulk purchases and inquire about other products, please contact our team to inform us of your purchase requirements. We will provide you with information such as quantity quotations, delivery dates, and transportation methods.\u003c\/p\u003e\u003c\/section\u003e\u003csection class=\"section\"\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is SIEMENS 3TK2821-1CB30?\u003c\/strong\u003e\u003cbr\u003eSIEMENS 3TK2821-1CB30 is a SIRIUS 3TK28 safety relay with relay output circuits.\u003c\/p\u003e\n\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eWhat control supply voltage does 3TK2821-1CB30 use?\u003c\/strong\u003e\u003cbr\u003eThe documented control supply voltage is 24 V AC\/DC.\u003c\/p\u003e\n\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eWhat terminal type does 3TK2821-1CB30 use?\u003c\/strong\u003e\u003cbr\u003eThis article number uses screw-type terminals.\u003c\/p\u003e\n\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eHow many normally open output circuits are provided?\u003c\/strong\u003e\u003cbr\u003eThree normally open output circuits are provided at terminals 13\/14, 23\/24 and 33\/34.\u003c\/p\u003e\n\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eDoes 3TK2821-1CB30 provide a normally closed signaling circuit?\u003c\/strong\u003e\u003cbr\u003eYes. A normally closed signaling circuit is provided at terminals 41\/42.\u003c\/p\u003e\n\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eWhat is the width of 3TK2821-1CB30?\u003c\/strong\u003e\u003cbr\u003eThe documented device width is 22.5 mm.\u003c\/p\u003e\n\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eWhat are terminals Y1\/Y2 used for?\u003c\/strong\u003e\u003cbr\u003eSiemens documentation identifies Y1\/Y2 for reset button and feedback circuit functions.\u003c\/p\u003e\n\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eCan 3TK2821 be used for contact expansion?\u003c\/strong\u003e\u003cbr\u003eSiemens operating documentation includes the 3TK2821 in a contact extension configuration. The complete safety circuit requirements should be checked before use.\u003c\/p\u003e\n\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eWhat applications can 3TK2821-1CB30 be considered for?\u003c\/strong\u003e\u003cbr\u003eIt can be considered for industrial safety relay circuits and contact extension functions after the safety requirements and circuit design have been checked.\u003c\/p\u003e\n\u003cbr\u003e\u003cp\u003e\u003cstrong\u003eWhat should be checked before ordering 3TK2821-1CB30?\u003c\/strong\u003e\u003cbr\u003eCheck the complete model number, 24 V AC\/DC supply requirement, screw-terminal configuration, required output contacts and existing safety circuit requirements before ordering.\u003c\/p\u003e\u003c\/section\u003e\u003c\/main\u003e\u003c\/div\u003e\u003c\/div\u003e","brand":"SIEMENS","offers":[{"title":"Default Title","offer_id":46496517029967,"sku":"GJL-SIEMENS-3TK2821-1CB30","price":78.98,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0710\/7569\/2623\/files\/3TK2821-1CB30.jpg?v=1787739327","url":"https:\/\/yunshuotrade.com\/products\/siemens-3tk2821-1cb30-safety-relay","provider":"yunshuotrade","version":"1.0","type":"link"}