{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1276-6NP36","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1276-6NP36","canonicalUrl":"https://aoctrl.com/siemens/3RT1276-6NP36","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1276-6NP36","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT1276-6NP36, vacuum contactor, size S12, rated control supply voltage 200-277 V, screw-type magnet coil terminals, main circuit stranded 70-240 mm².","salesMarkdown":"The Siemens 3RT1276-6NP36 is a SIRIUS-brand vacuum contactor in frame size S12. Vacuum contactors are used where the switching arc needs to be contained and extinguished in a vacuum envelope — common on medium-voltage motor starters and transformer switching, where air-break contactors would have trouble with the arc energy. The S12 frame tells you the physical size and the current-carrying capacity of the main poles. The coil is rated for 200-277 V AC/DC, so it lands on a standard 230 V or 277 V control supply without a transformer tap change. The magnet coil uses screw-type terminals, which is the standard termination for this class — no push-in or spring-cage on the coil circuit. Main circuit wiring accepts stranded cable from 70 mm² up to 240 mm², sized for the bolted connection on the S12 pole. Auxiliary contacts are present, so you get at least one N.O. or N.C. feedback pair built in without an add-on block. Fastening is by screw fixing, not DIN-rail snap-on. The contactor has a single 11 mm mounting hole — expect to bolt it to a backplate or mounting rail with an M10 or 3/8\" bolt. The S12 footprint is 160 mm wide, 214 mm tall, 225 mm deep, so plan for that envelope in the panel layout. That gives you some room to fit it into a tight cabinet, but the 225 mm depth is the dimension to watch when closing the door. These are minimums for arc flash and cooling — don't crowd the enclosure. ## Switching performance and duty This is a vacuum contactor, so the arc is quenched in a sealed vacuum bottle. Arcing time is 10-15 ms, and the coil pick-up and drop-out times are both 80-100 ms on AC or DC. That's a consistent, repeatable switching profile for process interlocks. Switching rates: 700 operations per hour at AC-1 (resistive), 250 at AC-2 (slip-ring motors), 750 at AC-3 (squirrel-cage motors), 250 at AC-4 (plugging/inching). The AC-3 and AC-3e rates are both 750 1/h, so it handles standard motor starting duty cycles well. The AC-4 limit of 250 1/h reflects the heavier arc wear from reversing or jogging. Electrical life will be lower and depends on the switched current and duty class. The auxiliary contact ratings at 24 V are 10 A, dropping to 2 A at 48 V and 60 V, and 1 A at 110 V. That's a resistive load curve — inductive loads will need derating or a suppression network across the aux contacts.","metaTitle":"Siemens 3RT1276-6NP36 SIRIUS Vacuum Contactor, S12, 200-277","metaDescription":"Siemens SIRIUS 3RT1276-6NP36 vacuum contactor, size S12. Rated coil 200-277 V AC/DC. Stranded main circuit 70-240 mm². Screw-type magnet coil terminals. Current lifecycle stage.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"225 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), max. 2x (0.75 ... 4 mm²)","Width":"160 mm","at AC":"80 ... 100 ms","at DC":"80 ... 100 ms","Height":"214 mm","Upwards":"10 mm","Forwards":"20 mm","Stranded":"70 ... 240 mm²","at 50 Hz":"0.4","at 60 Hz":"0.4","Downwards":"10 mm","Arcing Time":"10 ... 15 ms","At The Side":"10 mm","Rated Value":"200 ... 277 V","Initial Value":"0.8","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Screw-type terminals","Number Of Holes":"1","at AC-1 maximum":"700 1/h","at AC-2 maximum":"250 1/h","at AC-3 maximum":"750 1/h","at AC-4 maximum":"250 1/h","lifecycle_stage":"current","Auxiliary Switch":"Yes","During Operation":"-25 ... +60 °C","Fastening Method":"screw fixing","Full-Scale Value":"1.1","at AC-3e maximum":"750 1/h","Diameter Of Holes":"11 mm","Mounting Position":"+/-22,5° rotation possible on vertical mounting surface; can be tilted forward and backward by +/- 22.5° on vertical mounting surface; standing, on horizontal mounting surface","Size Of Contactor":"S12","Solid Or Stranded":"2x (0,5 ... 1,5 mm²), 2x (0,75 ... 2,5 mm²), max. 2x (0,75 ... 4 mm²)","Product Brand Name":"SIRIUS","Product Designation":"Vacuum contactor","at 24 V rated value":"10 A","at 48 V rated value":"2 A","at 60 V rated value":"2 A","Of Contactor Typical":"10 000 000","at 110 V rated value":"1 A","at 125 V rated value":"0.9 A","at 220 V rated value":"0.3 A","at 230 V rated value":"6 A","at 400 V rated value":"3 A","at 480 V rated value":"477 A","at 50 Hz rated value":"200 ... 277 V","at 500 V rated value":"2 A","at 60 Hz rated value":"200 ... 277 V","at 600 V rated value":"472 A","at 690 V rated value":"1 A","Side-By-Side Mounting":"Yes","at 1000 V rated value":"710 kW","For Auxiliary Contacts":"18 ... 14","Width Of Connection Bar":"25 mm","For Main Current Circuit":"Connection bar","at 200/208 V rated value":"150 hp","at 220/230 V rated value":"200 hp","at 460/480 V rated value":"400 hp","at 575/600 V rated value":"500 hp","Relative Humidity Minimum":"10 %","Of Main Circuit Rated Value":"8 kV","Thickness Of Connection Bar":"6 mm","at AC-3 rated value maximum":"1 000 V","at AC in hot operating state":"96 W","at AC-3e rated value maximum":"1 000 V","at AC-4 at 400 V rated value":"430 A","safety-related switching OFF":"Yes","Substance Prohibitance (Date)":"05/01/2012","Design Of The Surge Suppressor":"with varistor","Of Auxiliary Circuit Rated Value":"6 kV","For Auxiliary And Control Circuit":"screw-type terminals","Function Module For Communication":"No","With Type Of Assignment 2 Required":"gG: 800 A (690 V, 50 kA), aM: 630 A (690 V, 50 kA), BS88: 800 A (415 V, 50 kA)","Without Load Current Share Typical":"3.6 W","closing power of magnet coil at DC":"800 W","holding power of magnet coil at DC":"3.6 W","At Contactor For Auxiliary Contacts":"Screw-type terminals","With Type Of Coordination 1 Required":"gG: 800 A (690 V, 100 kA)","operational current at AC-12 maximum":"10 A","at AC in hot operating state per pole":"32 W","for AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14), 1x 12","number of NO contacts for main contacts":"3","reference code according to IEC 81346-2":"Q","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Number Of Poles For Main Current Circuit":"3","voltage at PLC-control input rated value":"24 V","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","mirror contact according to IEC 60947-4-1":"Yes","Type Of Voltage Of The Control Supply Voltage":"AC/DC","type of PLC-control input according to IEC 60947-1":"Type 2","contact rating of auxiliary contacts according to UL":"A600 / Q600","Of Main Circuit With Degree Of Pollution 3 Rated Value":"1 000 V","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","operating range factor of the voltage at PLC-control input":"0.8 ... 1.1","Of Auxiliary Circuit With Degree Of Pollution 3 Rated Value":"500 V","For Short-Circuit Protection Of The Auxiliary Switch Required":"gG: 10 A (500 V, 1 kA)","minimum cross-section in main circuit at maximum AC-1 rated value":"370 mm²","number of NC contacts for auxiliary contacts instantaneous contact":"2","number of NO contacts for auxiliary contacts instantaneous contact":"2","Of The Contactor With Added Electronically Optimized Auxiliary Switch Block Typical":"5 000 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/731e10ab404ab79d6a2016f8f75fbb03.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=432118&mlfb=3RT1276-6NP36","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1276-6NP36/alternatives.json"},"ai":{"faq":[{"question":"What is the main circuit cable size range for this contactor?","answer":"The main circuit accepts stranded cable from 70 mm² to 240 mm², terminated with a bolted connection."},{"question":"What is the coil voltage rating?","answer":"The coil is rated 200-277 V AC/DC, covering standard 230 V and 277 V control supplies."},{"question":"What are the mounting clearances needed?","answer":"Minimum clearances: 10 mm upwards, 10 mm downwards, 10 mm at the sides, and 20 mm forwards from the contactor body."},{"question":"Does this contactor have auxiliary contacts built in?","answer":"Yes, the contactor includes an auxiliary switch, so at least one set of auxiliary contacts is present without needing an add-on block."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1276-6NP36","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/3RT1276-6NP36 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}}