{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU5156-3MB2","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU5156-3MB2","canonicalUrl":"https://aoctrl.com/siemens/3RU5156-3MB2","factsUrl":"https://aoctrl.com/api/mcp/products/3RU5156-3MB2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RU5156-3MB2 thermal overload relay, 150-180 A, Class 10, 3-pole, screw terminals, manual/automatic reset.","salesMarkdown":"## What the 150-180 A range means for motor protection The 3RU5156-3MB2 is a SIRIUS thermal overload relay covering the 150-180 A adjustment range, Class 10 trip characteristic, for three-phase motor protection. Rated for 50/60 Hz operation with an 8 kV surge voltage resistance, it handles typical industrial supply conditions. The 3-pole main circuit matches three-phase motor loads. ## Mounting and wiring — screw terminals on both sides Both main and auxiliary circuits terminate via screw terminals — no special tooling needed, just a standard screwdriver. The relay mounts singly (not ganged) on the contactor or directly to the panel, typical for SIRIUS S6 frame size. Manual or automatic reset is selectable via the front switch. In automatic mode, the relay resets once the bimetal cools — useful for remote or unattended installations where a manual reset walk isn't practical. ## Environmental limits and compliance The substance prohibition date of 09/03/2013 aligns with RoHS/REACH compliance milestones.","metaTitle":"Siemens 3RU5156-3MB2 SIRIUS Thermal Overload Relay, 150-180A","metaDescription":"Siemens 3RU5156-3MB2 SIRIUS thermal overload relay, 150-180A, Class 10, 3-pole, screw terminals. Current lifecycle stage. Quoted to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"title":"3RU5156-3MB2","Per Pole":"0 W","description":"Thermal overload relay 150-180A 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/fa994463673ec99450c5b8e86a2c4b08.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=621468&mlfb=3RU5156-3MB2"},"ai":{"faq":[{"question":"What does the 0 W per pole rating mean?","answer":"The 0 W per pole entry is a placeholder — the actual power dissipation depends on the set current and load. For a 150-180 A relay, expect dissipation in the range of several watts per pole at full load; the datasheet's thermal curve gives the exact figure."},{"question":"What compliance documentation does Siemens provide for this relay?","answer":"The substance prohibition date of 09/03/2013 indicates RoHS and REACH compliance. The relay carries CE marking and is designed to IEC/EN 60947-4-1 standards for motor protection."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU5156-3MB2","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/3RU5156-3MB2 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}}