{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3UG4511-2AP20","brand":"Siemens","brandSlug":"siemens","productSlug":"3UG4511-2AP20","canonicalUrl":"https://aoctrl.com/siemens/3UG4511-2AP20","factsUrl":"https://aoctrl.com/api/mcp/products/3UG4511-2AP20","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS phase monitoring relay, 3UG4511-2AP20, 320-500 VAC 50/60 Hz, 3 A rated output, IP20, 22.5 mm snap-on.","salesMarkdown":"The Siemens 3UG4511-2AP20 is a SIRIUS phase monitoring relay — a single-function device that watches for phase loss, phase sequence, and undervoltage on three-phase AC supplies. It's the kind of part you drop into a motor feeder or a pump panel to keep the contactor from closing when the incoming line isn't healthy. Rated for 320 to 500 VAC at both 50 and 60 Hz, it covers the common European and North American 400 V distribution voltages. The output is a single changeover contact rated 3 A at 250/400 VAC, 50/60 Hz — enough to drive a contactor coil or a PLC input directly. The IP20 finger-safe housing means it's meant for an enclosed panel, not a washdown area. The 320-500 VAC range is the nominal monitoring window — the relay will pick up and indicate healthy when all three phases are present and within that band. Below 320 V it drops out; above 500 V it's outside spec. The 50/60 Hz dual rating means you don't need a different variant for 60 Hz installations. Output contact ratings: 3 A at 250 VAC and 3 A at 400 VAC (both at 50/60 Hz), plus 1 A at 24 VDC, 0.2 A at 125 VDC, and 0.1 A at 250 VDC. That DC curve is typical for a relay of this size — fine for pilot duty, but don't plan on switching a DC motor contactor directly at the higher current. The relay has an auto-reset function — once the fault clears and the supply returns to normal, it will re-energize the output without a manual pushbutton. That's convenient for remote or unattended panels, but if you need a latching fault indication, you'll want to add a separate manual-reset relay or use the undervoltage detection option on a different model (this one does not have undervoltage detection). A green LED on the front shows operating status — handy for quick troubleshooting without dragging out a meter. The terminal block accepts 2 x 0.2 to 2.5 mm² solid or stranded wire (24 to 16 AWG), which covers most control-circuit wiring. Dimensions: 22.5 mm wide, 84 mm tall, 91 mm deep. Snap-on mounting with zero clearance required on all sides — upwards, downwards, forwards, backwards, and sideways all read 0 mm. That means you can butt it against other components or the side of the enclosure without worrying about heat dissipation or access for wiring.","metaTitle":"Siemens 3UG4511-2AP20 SIRIUS Phase Monitoring Relay, 320-500","metaDescription":"Siemens SIRIUS 3UG4511-2AP20 phase monitoring relay, 320-500 VAC 50/60 Hz, 3 A output, IP20, snap-on 22.5 mm. Active production, 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":"24 ... 16","Width":"22.5 mm","Height":"84 mm","Upwards":"0 mm","at 24 V":"1 A","Forwards":"0 mm","Stranded":"24 ... 16","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":"1","Mounting Position":"any","Product Brand Name":"SIRIUS","Asymmetry Detection":"No","Between The Outputs":"Yes","Degree Of Pollution":"3","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","for AWG cables solid":"2x (24 ... 16)","Design Of The Product":"1 function","Overvoltage Detection":"No","For Auxiliary Contacts":"1","Undervoltage Detection":"No","Phase Failure Detection":"No","for AWG cables stranded":"2x (24 ... 16)","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":"spring-loaded 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":"0.25 ... 1.5 mm²","Number Of Poles For Main Current Circuit":"3","Finely Stranded Without Core End Processing":"0.25 ... 1.5 mm²","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/3UG4511-2AP20/alternatives.json"},"ai":{"faq":[{"question":"What are the key ratings for the 3UG4511-2AP20?","answer":"It monitors 320-500 VAC three-phase supplies at 50 or 60 Hz. The output relay is rated 3 A at 250/400 VAC, 1 A at 24 VDC. It has auto-reset, an LED status indicator, and snap-on DIN-rail mounting in a 22.5 mm wide housing."},{"question":"What is the depth of the 3UG4511-2AP20?","answer":"The depth is 91 mm. Width is 22.5 mm, height is 84 mm."},{"question":"What wire sizes does the 3UG4511-2AP20 accept?","answer":"The terminals accept 2 x 0.2 to 2.5 mm² solid or stranded wire, which corresponds to 24 to 16 AWG."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3UG4511-2AP20","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/3UG4511-2AP20 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}}