{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5TT5842-2","brand":"Siemens","brandSlug":"siemens","productSlug":"5TT5842-2","canonicalUrl":"https://aoctrl.com/siemens/5TT5842-2","factsUrl":"https://aoctrl.com/api/mcp/products/5TT5842-2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5TT5842-2 insta contactor, 40 A at 400 V AC, 24 V AC coil, 2 NO + 2 NC contacts, IP20, 3 MW, 71 mm depth.","salesMarkdown":"## 40 A at 400 V — the real-world switching limit The 5TT5842-2 is a SENTRON insta contactor rated for 40 A operational current at 400 V AC. That 40 A figure is the AC-1 resistive load rating — the current you can count on for heater banks, lighting panels, and similar steady loads where inrush isn't a factor. The 24 V AC coil means this is a control-voltage part, not a 230 V coil variant; make sure your control transformer and PLC output card are rated for the coil draw before wiring it in. ## Contact configuration and panel fit Two normally-open and two normally-closed contacts give you flexibility: you can break both poles of a single-phase load, or use one NO for the load and the other NO for a pilot light, with the NC contacts feeding back status to the PLC. The 3 MW modular width means it occupies three 18 mm DIN-rail slots — a standard footprint for a 40 A contactor in a distribution board. Dimensions are 90 mm high, 54 mm wide, and 71 mm deep, so it fits behind a standard 100 mm deep enclosure door. The installation note calls for spacers to ensure heat dissipation — don't pack it tight against other heat-generating devices without that air gap, or the thermal rating derates faster than you expect.","metaTitle":"Siemens 5TT5842-2 SENTRON Insta Contactor, 40 A","metaDescription":"Siemens 5TT5842-2 SENTRON insta contactor, 40 A at 400 V AC, 24 V AC coil, 2 NO + 2 NC contacts. Active production, IP20, 3 MW. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"71 mm","Width":"54 mm","Height":"90 mm","Maximum":"440 V","Minimum":"440 V","Rated Value":"24 V","lifecycle_stage":"current","Installation Depth":"0 mm","Product Brand Name":"SENTRON","Product Designation":"Insta contactor","Rated Value Maximum":"24 V","protection class IP":"IP20","Design Of The Product":"2 NO contacts 2 NC contacts","number of NC contacts":"2","number of NO contacts":"2","Installation Or Assembly Note":"provision must be made for spacers to ensure heat dissipation","Number Of Modular Width Units":"3","operational current at AC rated value":"40 A","Type Of Voltage Of The Operating Voltage":"AC","Product Extension Installable Supplementary Devices":"Yes","Type Of Voltage Of The Operating Voltage For Actuation":"AC","Switching Capacity Active Power With Incandescent Lamp Load":"4 000 W","power loss [W] for rated value of the current at AC in hot operating state per pole":"4 W"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/c21ef046c145501df0fb05bfddf96dcd.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=438005&mlfb=5TT5842-2","alternativesUrl":"https://aoctrl.com/api/mcp/products/5TT5842-2/alternatives.json"},"ai":{"faq":[{"question":"What is the switching capacity for incandescent lamp loads?","answer":"The 5TT5842-2 is rated to switch up to 4,000 W of incandescent lamp load. That's the tungsten inrush ceiling — filament lamps can pull 10–15× rated current on cold start, so this rating accounts for that surge without welding the contacts."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5TT5842-2","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/5TT5842-2 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}}