{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH1344-1UM40-0KV0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH1344-1UM40-0KV0","canonicalUrl":"https://aoctrl.com/siemens/3RH1344-1UM40-0KV0","factsUrl":"https://aoctrl.com/api/mcp/products/3RH1344-1UM40-0KV0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS auxiliary contactor, 3RH1344-1UM40-0KV0, size S00, 4 NO + 0 NC, 220 V DC coil with varistor, screw and snap-on mounting, IP20 front.","salesMarkdown":"The 3RH1344-1UM40-0KV0: This is the contactor you reach for when the control circuit needs to multiply a 220 V DC pilot signal into four isolated NO contact paths — for example, extending a PLC digital output to drive multiple contactor coils, indicator lamps, or safety interlock chains. The varistor across the coil means you do not need to add an external suppression diode or RC snubber; the part handles its own back-EMF clamping, which simplifies panel wiring and reduces the component count per rail. Rated operational currents are given per IEC utilization category at several voltages: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, 2 A at 500 V, and 1 A at 690 V. At 110 V the rating is 1 A, and at 220 V it is 0.27 A — the 220 V figure is the lowest in the set, so if you are switching a 220 V AC load, the contact rating is the binding constraint, not the 10 A at 24 V. The 3RH1344-1UM40-0KV0 mounts by screw fixing or snap-on onto a DIN rail. That range covers most enclosure layouts without needing a special adapter. Footprint is 45 mm wide by 57.5 mm high by 111 mm deep — a size S00 envelope that fits alongside a 3RT10 or 3RT20 contactor in the same rail section. Terminals accept solid conductors in three combinations: two conductors of 0.5 to 1.5 mm², two of 0.75 to 2.5 mm², or two of 4 mm². That covers the typical control wiring range from 1.5 mm² for pilot circuits up to 4 mm² for short power-feed runs. The screw-clamp design is standard for the SIRIUS family — no special tooling needed beyond a Pozidriv bit. Shock resistance is specified at 10 g for 5 ms and 5 g for 10 ms, which is adequate for mounting on a panel door or inside a vibrating machine enclosure. The coil draws 3.2 W during closing and holding at DC, which is a constant DC power draw — no inrush spike like an AC coil. That makes it predictable for power-supply budgeting in a 24 V DC or 220 V DC control bus. The part carries a RoHS substance prohibition compliance date of July 1, 2006, which aligns with the EU RoHS directive. No UL, CSA, or CE mark is explicitly listed in the spec record, but the SIRIUS family is typically certified to IEC/EN 60947 — verify the specific certification marking on the nameplate if your project requires a third-party agency listing.","metaTitle":"Siemens 3RH1344-1UM40-0KV0 SIRIUS Auxiliary Contactor, 4 NO","metaDescription":"Siemens SIRIUS 3RH1344-1UM40-0KV0 auxiliary contactor, size S00, 4 NO contacts, 220 V DC coil with varistor, IP20 front, screw/snap-on mount, current production.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"111 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), 2x 4 mm²","Width":"45 mm","Height":"57.5 mm","Rated Value":"220 V","Initial Value":"0.8","During Storage":"-55 ... +80 °C","Leading Contact":"0","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","During Transport":"-55 ... +80 °C","Fastening Method":"screw and snap-on mounting","Full-Scale Value":"1.1","Shock Resistance":"10g / 5 ms and 5g / 10 ms","Delayed Switching":"0","Lagging Switching":"0","Mounting Position":"+/-180° rotation possible on vertical mounting surface; can be tilted forward and backward by +/- 22.5° on vertical mounting surface","Size Of Contactor":"S00","Product Brand Name":"SIRIUS","Contact Reliability":"one incorrect switching operation of 100 million switching operations (17 V, 1 mA)","Degree Of Pollution":"3","Product Designation":"Auxiliary contactor","at 24 V rated value":"10 A","Of Contactor Typical":"10 000 000","at 110 V rated value":"1 A","at 220 V rated value":"0.27 A","at 230 V rated value":"6 A","at 400 V rated value":"3 A","at 500 V rated value":"2 A","at 690 V rated value":"1 A","Instantaneous Contact":"4","For Auxiliary Contacts":"0","Make-Before-Break Switching":"0","Substance Prohibitance (Date)":"07/01/2006","Design Of The Surge Suppressor":"with varistor","protection class IP on the front":"IP20","Product Extension Auxiliary Switch":"No","closing power of magnet coil at DC":"3.2 W","holding power of magnet coil at DC":"3.2 W","Surge Voltage Resistance Rated Value":"6 kV","operational current at AC-12 maximum":"10 A","for AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14), 1x 12","reference code according to IEC 81346-2":"K","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","Touch Protection Against Electrical Shock":"finger-safe","with low demand rate according to SN 31920":"40 %","Of Auxiliary Contacts Instantaneous Contact":"0","with high demand rate according to SN 31920":"75 %","number of NC contacts for auxiliary contacts":"4","number of NO contacts for auxiliary contacts":"4","Type Of Voltage Of The Control Supply Voltage":"DC","Identification Number And Letter For Switching Elements":"44 E","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Required Spacing With Side-By-Side Mounting At The Side":"0 mm","Type Of Electrical Connection For Auxiliary And Control Circuit":"screw-type terminals","insulation voltage with degree of pollution 3 at AC rated value":"690 V","Design Of The Fuse Link For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gL/gG: 10 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=136842&mlfb=3RH1344-1UM40-0KV0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RH1344-1UM40-0KV0/alternatives.json"},"ai":{"faq":[{"question":"What is the closest functional second-source or alternative?","answer":"The peer contactors 3RT1015-1BB42, 3RT2026-1KB40, and 3RT2028-1BB40 are in the same SIRIUS family but are power contactors, not auxiliary contactors. The 3RH1344-1UM40-0KV0 is a dedicated auxiliary contactor with four NO contacts and a 220 V DC coil with varistor. A direct swap would require verifying the coil voltage, contact configuration, and mounting footprint — the 3RT series has different coil options and is physically sized for motor switching, not auxiliary control. No single drop-in replacement exists without rewiring or changing the control voltage."},{"question":"What is the depth of this contactor?","answer":"The depth is 111 mm. The width is 45 mm and the height is 57.5 mm, giving a size S00 footprint."},{"question":"What conductor cross-sections does the terminal accept?","answer":"The screw terminals accept solid conductors in these combinations: two conductors of 0.5 to 1.5 mm², two of 0.75 to 2.5 mm², or two of 4 mm²."},{"question":"Will this fit into a panel designed for a 3RT1015-1BB42?","answer":"Both are size S00, so the mounting footprint (45 mm wide) and DIN-rail clip are the same. However, the 3RT1015-1BB42 is a power contactor with a different coil voltage and contact arrangement. The 3RH1344-1UM40-0KV0 is an auxiliary contactor with 4 NO contacts and a 220 V DC coil. It will physically mount in the same rail slot but the wiring and function are different — it is not a direct functional replacement."},{"question":"What compliance documentation is available for this part?","answer":"The spec record shows a RoHS substance prohibition compliance date of July 1, 2006. No UL, CSA, or CE marks are explicitly listed in the spec data. The SIRIUS family typically carries IEC/EN 60947 certification; check the nameplate marking for specific agency approvals."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH1344-1UM40-0KV0","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/3RH1344-1UM40-0KV0 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}}