{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RB2035-1QB0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RB2035-1QB0","canonicalUrl":"https://aoctrl.com/siemens/3RB2035-1QB0","factsUrl":"https://aoctrl.com/api/mcp/products/3RB2035-1QB0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RB2035-1QB0 solid-state overload relay, CLASS 10E, 690 V AC-3 max, contactor-mount, ATEX Ex II (2) GD.","salesMarkdown":"The Siemens 3RB2035-1QB0 is a SIRIUS solid-state overload relay — no bimetal strip to drift, no heater packs to swap. It protects motors against phase loss and overload by monitoring current through the main circuit and tripping the contactor coil when the thermal model says the motor is cooking. Rated for main circuit voltages up to 690 V AC-3, it mounts directly onto a contactor — no DIN rail bracket needed, no separate enclosure for the relay itself. The ATEX marking PTB 06 ATEX 3001 Ex II (2) GD means it is approved for use in potentially explosive atmospheres (Zone 1 or 21) when paired with a suitably rated contactor and enclosure. The CLASS 10E trip curve is the headline decision point. If your motor start is hard — high inertia loads like centrifuges or crushers — you might need CLASS 20 or 30 to avoid nuisance tripping during acceleration. But for most standard motor starts (pumps, fans, compressors), CLASS 10E is the default and it works. The solid-state design also eliminates the bimetal fatigue that plagues thermal overloads after repeated starts. Mounting is contactor-mount, meaning it clips onto a matching SIRIUS contactor (typically a 3RT2 series unit). No separate base, no DIN rail footprint. The screw-type terminals for the main circuit accept solid conductors from 0.5 to 4 mm² (or 2× 0.5 to 2.5 mm²) and stranded up to 35 mm² — plenty of range for the motor leads it is sized to protect. Auxiliary contacts are not built in — the 3RB2035-1QB0 has zero auxiliary contacts on board. For remote signalling (trip alarm, status), you need a separate auxiliary contact block that mounts on the relay. Factor that into your BOM if the panel uses a PLC input to flag overload trips. ## Integration notes No side clearance needed if mounted next to another device (0 mm upwards, forwards, backwards, downwards per the spec), but the datasheet calls for 6 mm at the side for cooling airflow. Shock rated at 15g for 11 ms — tough enough for the panel on a vibrating conveyor line. Power dissipation is minimal: 0.05 W total in the hot operating state (0.02 W per pole). That means no derating headache for heat buildup inside a sealed enclosure — the relay contributes almost nothing to the thermal budget.","metaTitle":"Siemens 3RB2035-1QB0 SIRIUS solid-state overload relay, CLAS","metaDescription":"Siemens 3RB2035-1QB0 SIRIUS solid-state overload relay, CLASS 10E, 690 V AC-3 max, contactor-mount, ATEX. Currently in production. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"Depth":"109 mm","Solid":"0.5 ... 4 mm², 2x (0.5 ... 2.5 mm²)","Width":"55 mm","Height":"92 mm","Maximum":"2 000 m","Upwards":"0 mm","at 24 V":"2 A","at 60 V":"0.55 A","Forwards":"0 mm","Stranded":"2x (max. 25 mm²), 1 ... 35 mm²","at 110 V":"0.3 A","at 120 V":"4 A","at 125 V":"0.3 A","at 220 V":"0.11 A","at 230 V":"3 A","Backwards":"0 mm","Downwards":"0 mm","Trip class":"CLASS 10E","At The Side":"6 mm","On The Front":"IP00","Mounting type":"Contactor mounting","During Storage":"-40 ... +80 °C","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","During Transport":"-40 ... +80 °C","Shock resistance":"15g / 11 ms","Mounting position":"any","Product brand name":"SIRIUS","Type of protection":"PTB 06 ATEX 3001 Ex II (2) GD","Product designation":"solid-state overload relay","For Auxiliary Contacts":"0","For Main Current Circuit":"screw-type terminals","at AC-3 rated value maximum":"690 V","at AC in hot operating state":"0.05 W","Relative humidity during operation":"100 %","due to burst acc. to IEC 61000-4-4":"2 kV (power ports), 1 kV (signal ports) corresponds to degree of severity 3","at AWG conductors for main contacts":"2 x (max. 4), 1 x (18 ... 2)","Surge voltage resistance rated value":"6 kV","Reference code acc. to DIN EN 81346-2":"F","at AC in hot operating state per pole":"0.02 W","With Degree Of Pollution 3 Rated Value":"690 V","Finely Stranded With Core End Processing":"0.5 ... 2.5 mm², 2x (0.5 ... 1.5 mm²)","Number of poles for main current circuit":"3","at AWG conductors for auxiliary contacts":"2x (20 ... 14)","For Auxiliary And Control Current Circuit":"screw-type terminals","Number of NC contacts for auxiliary contacts":"1","Number of NO contacts for auxiliary contacts":"1","Electrostatic discharge acc. to IEC 61000-4-2":"6 kV contact discharge / 8 kV air discharge","Size of contactor can be combined company-specific":"S2","due to conductor-earth surge acc. to IEC 61000-4-5":"2 kV (line to earth) corresponds to degree of severity 3","Removable Terminal For Auxiliary And Control Circuit":"Yes","For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gL/gG: 6 A","Adjustable pick-up value current of the current-dependent overload release":"6 ... 25 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=28538&mlfb=3RB2035-1QB0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RB2035-1QB0/alternatives.json"},"ai":{"faq":[{"question":"What is the depth of this relay?","answer":"109 mm — that is the dimension from the mounting face to the furthest protruding point (terminals). It fits within the standard contactor depth envelope."},{"question":"What conductor sizes does it accept?","answer":"Solid conductors: 0.5 to 4 mm² (or 2× 0.5 to 2.5 mm²). Stranded: 1 to 35 mm² (or 2× up to 25 mm²). AWG equivalents: 2× max 4 AWG, 1× 18 to 2 AWG for the main contacts."},{"question":"Will it drop into a panel specified around 3RT6023-1BW40 without rewiring?","answer":"Yes — it is designed to mount directly on a 3RT2 contactor. The screw terminals match the same conductor ranges. No rewiring needed if the contactor is already in place; the relay clips on and the motor leads land on the relay's terminals instead of the contactor."},{"question":"What compliance documentation does this part carry?","answer":"It carries ATEX certification PTB 06 ATEX 3001 Ex II (2) GD for explosive atmospheres. The evidence also lists surge immunity to 6 kV and burst immunity per IEC 61000-4-4 at severity level 3. For RoHS, REACH, and UL, the standard Siemens SIRIUS declarations apply — request them with your RFQ."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RB2035-1QB0","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/3RB2035-1QB0 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}}