{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3UG4511-1BP20","brand":"Siemens","brandSlug":"siemens","productSlug":"3UG4511-1BP20","canonicalUrl":"https://aoctrl.com/siemens/3UG4511-1BP20","factsUrl":"https://aoctrl.com/api/mcp/products/3UG4511-1BP20","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS phase monitoring relay, 3UG4511-1BP20, 320-500 VAC 50/60 Hz, 3 A rated contact, IP20, snap-on DIN-rail mount.","salesMarkdown":"## Phase monitoring relay for 320-500 VAC lines The Siemens SIRIUS 3UG4511-1BP20 is a single-function phase monitoring relay designed for AC systems. It monitors a 320-500 VAC supply at 50 or 60 Hz and provides a switched output rated at 3 A at 250 V or 400 V (50/60 Hz). The unit has a single changeover contact (SPDT) rated 1 A at 24 V, 0.2 A at 125 V, and 0.1 A at 250 V for DC loads. An LED indicates the operating status, and the relay offers an auto-reset function after a fault clears — useful for unattended restart scenarios. IP20 protection means it is suitable for installation inside a closed panel only. The 3 A contact rating at 250/400 V AC is the thermal current (Ith) for resistive loads; for inductive or DC loads, derate to the values listed (1 A at 24 V DC, 0.2 A at 125 V DC, 0.1 A at 250 V DC). The relay does not detect asymmetry, overvoltage, or undervoltage — it only monitors phase loss or phase sequence on a three-phase supply. If your application requires asymmetry detection, you would need a different SIRIUS variant (e.g., 3UG4611).","metaTitle":"Siemens 3UG4511-1BP20 SIRIUS Phase Monitoring Relay, 320-500","metaDescription":"Siemens SIRIUS 3UG4511-1BP20 phase monitoring relay, 320-500 VAC 50/60 Hz, 3 A rated contact, IP20, snap-on DIN mount. Current lifecycle stage. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"NRND","categoryPath":["Process / Temperature Controllers"],"specifications":{"Depth":"91 mm","Solid":"20 ... 14","Width":"22.5 mm","Height":"92 mm","Upwards":"0 mm","at 24 V":"1 A","Forwards":"0 mm","Stranded":"20 ... 14","at 125 V":"0.2 A","at 250 V":"0.1 A","Backwards":"0 mm","Downwards":"0 mm","auto-RESET":"Yes","At The Side":"0 mm","Initial Value":"1","During Storage":"-40 ... +85 °C","For Monitoring":"AC","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","During Transport":"-40 ... +85 °C","Fastening Method":"snap-on mounting","Full-Scale Value":"1","Product Function":"Phase monitoring relay","Delayed Switching":"2","Mounting Position":"any","Product Brand Name":"SIRIUS","Asymmetry Detection":"No","Between The Outputs":"Yes","Degree Of Pollution":"3","at AWG cables solid":"2x (20 ... 14)","display version LED":"Yes","protection class IP":"IP20","at 250 V at 50/60 Hz":"3 A","at 400 V at 50/60 Hz":"3 A","at 50 Hz rated value":"320 ... 500 V","at 60 Hz rated value":"320 ... 500 V","Design Of The Product":"1 function","Overvoltage Detection":"No","For Auxiliary Contacts":"2","Undervoltage Detection":"No","at AWG cables stranded":"2x (20 ... 14)","Phase Failure Detection":"No","Between Input And Output":"Yes","measurable voltage at AC":"320 ... 500 V","Phase Sequence Recognition":"Yes","Of The Control Supply Voltage":"AC","Overvoltage Detection 3 Phase":"No","Substance Prohibitance (Date)":"05/01/2012","Type Of Electrical Connection":"screw-type terminals","Undervoltage Detection 3 Phases":"No","Voltage Window Recognition 3 Phase":"No","operational current at 17 V minimum":"5 mA","Surge Voltage Resistance Rated Value":"6 kV","With Degree Of Pollution 3 Rated Value":"690 V","due to burst according to IEC 61000-4-4":"2 kV","number of NC contacts delayed switching":"0","number of NO contacts delayed switching":"0","reference code according to IEC 81346-2":"K","Finely Stranded With Core End Processing":"0.5 ... 2.5 mm²","Number Of Poles For Main Current Circuit":"3","Tightening Torque With Screw-Type Terminals":"0.8 ... 1.2 N·m","shock resistance according to IEC 60068-2-27":"sinusoidal half-wave 15g / 11 ms","Between The Voltage Supply And Other Circuits":"Yes","operating frequency with 3RT2 contactor maximum":"5 000 1/h","vibration resistance according to IEC 60068-2-6":"1 ... 6 Hz: 15 mm, 6 ... 500 Hz: 2g","Adjustable Open/Closed-Circuit Current Principle":"No","Mechanical Service Life (Operating Cycles) Typical":"10 000 000","electrostatic discharge according to IEC 61000-4-2":"6 kV contact discharge / 8 kV air discharge","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Thermal Current Of The Switching Element With Contacts Maximum":"5 A","continuous current of the DIAZED fuse link of the output relay":"4 A","Product Component Removable Terminal For Auxiliary And Control Circuit":"Yes"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":null,"alternativesUrl":"https://aoctrl.com/api/mcp/products/3UG4511-1BP20/alternatives.json"},"ai":{"faq":[{"question":"What are the key ratings for this phase monitoring relay?","answer":"It monitors 320-500 VAC at 50/60 Hz, has a 3 A rated contact at 250/400 V AC, and a 1 A contact at 24 V DC. It snaps onto a 35 mm DIN rail and is IP20 rated."},{"question":"Can the 3UG4511-1BP20 be used for undervoltage or overvoltage detection?","answer":"No, this relay monitors phase sequence and phase loss only. It does not detect undervoltage, overvoltage, or asymmetry."},{"question":"What is the mounting position and temperature range?","answer":"It can be mounted in any position, operates from -25 to +60 °C, and stores from -40 to +85 °C."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3UG4511-1BP20","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/3UG4511-1BP20 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}}