{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU5156-2HB2","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU5156-2HB2","canonicalUrl":"https://aoctrl.com/siemens/3RU5156-2HB2","factsUrl":"https://aoctrl.com/api/mcp/products/3RU5156-2HB2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS thermal overload relay, 3RU5156-2HB2, size S6, 55-80 A range, Class 10 trip, 3-pole, screw terminals, current lifecycle stage.","salesMarkdown":"## What this relay does in the panel The Siemens 3RU5156-2HB2 is a SIRIUS thermal overload relay sized for motor protection in the 55-80 A range, Class 10 trip curve. The 55-80 A window means it catches the full-load current of a motor in that band; the Class 10 trip gives you a 10-second maximum lock-rotor time before the bimetals open the auxiliary contact. That matters when you're coordinating with a contactor that can handle a 7x inrush for a few seconds but not a sustained stall. ## Size S6 — what the frame means for integration Size S6 is the physical frame — this is a larger relay, not a compact S00 or S0. It mounts standalone (single mounting) with screw terminals. The 55-80 A range and S6 body pair naturally with a contactor in the same frame class, typically the Siemens 3RT106 or similar S6 contactor. Panel space is the constraint: the S6 footprint is wider and deeper than the smaller sizes, so verify the DIN rail or backplate layout before committing the BOM. The manual/automatic reset selector on the front gives the commissioning engineer a choice — manual for troubleshooting, auto for unattended restart. ## Electrical environment — surge and frequency Rated surge voltage resistance is 8 kV, which puts it in the typical industrial panel category for 400/480 V systems — it handles switching transients from contactor coils and nearby VFDs without flashover. Operating frequency is 50-60 Hz, so it's agnostic between 50 Hz European and 60 Hz North American line frequencies.","metaTitle":"Siemens 3RU5156-2HB2 SIRIUS Thermal Overload Relay, 55-80 A,","metaDescription":"Siemens SIRIUS 3RU5156-2HB2 thermal overload relay, 55-80 A, Class 10, size S6. Current lifecycle stage. Sourced to order against an RFQ through independent distribution.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"title":"3RU5156-2HB2","Per Pole":"0 W","description":"Thermal overload relay 55-80 A size S6, class 10 for motor protection for single mounting main circuit: screw terminal AUX. circuit: screw terminal manual automatic reset","lifecycle_stage":"current","During Transport":"-55 ... +80 °C","Product Brand Name":"SIRIUS","Product Designation":"Thermal overload relay","Substance Prohibitance (Date)":"09/03/2013","Operating Frequency Rated Value":"50 ... 60 Hz","Relative Humidity During Operation":"0 ... 90 %","Surge Voltage Resistance Rated Value":"8 kV","Number Of Poles For Main Current Circuit":"3"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/c2c526b6f2f59ebc87c3da103680f6a1.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=621461&mlfb=3RU5156-2HB2"},"ai":{"faq":[{"question":"Where can I buy 3RU5156-2HB2 and how is it quoted?","answer":"This part is sourced to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm price and lead time."},{"question":"What is the adjustable current range of 3RU5156-2HB2?","answer":"The thermal overload relay covers a 55-80 A adjustable current range, with a Class 10 trip characteristic. It is a 3-pole device for three-phase motor protection."},{"question":"What compliance documentation does Siemens provide for 3RU5156-2HB2?","answer":"The part carries a Substance Prohibitance date of 09/03/2013, indicating compliance with RoHS and REACH substance restrictions as of that date. Standard Siemens documentation includes the CE declaration and manufacturer's declaration for the IEC 60947 series."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU5156-2HB2","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/3RU5156-2HB2 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}