{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3VA9978-0AA11","brand":"Siemens","brandSlug":"siemens","productSlug":"3VA9978-0AA11","canonicalUrl":"https://aoctrl.com/siemens/3VA9978-0AA11","factsUrl":"https://aoctrl.com/api/mcp/products/3VA9978-0AA11","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON, auxiliary switch changeover contacts type HP (14 mm), 3VA9978-0AA11, 10 A thermal current, for 3VA4/5/6 circuit breakers.","salesMarkdown":"The Siemens SENTRON 3VA9978-0AA11 is an auxiliary switch with changeover contacts, type HP, designed as a snap-on accessory for 3VA4, 3VA5, and 3VA6 molded-case circuit breakers. It provides remote status indication — open/closed/tripped — via its changeover contact set, wired back to a PLC or indicator lamp in the panel. Rated thermal current (Ith) is 10 A, which sets the continuous current-carrying capacity of the contacts under open-air conditions. The actual switching capacity depends on the load type and voltage: per the datasheet, at AC-15 (solenoid/contactor control) it handles 6 A up to 48 V and derates to 0.6 A at 600 V; at DC-13 (solenoid/electromagnet with parallel diode) it carries 3 A at 12/24 V and drops to 0.1 A at 250 V. The 14 mm housing width matches the standard 14 mm per-pole module footprint of the host breaker, so it occupies one additional module space on the DIN rail. Stripped length for the screw-clamp terminals is 15 mm (0.6 in), accepting conductors up to the breaker's terminal capacity. This auxiliary switch snaps onto the left or right side of a 3VA4, 3VA5, or 3VA6 breaker frame. It does not require additional DIN-rail space beyond the breaker's own mounting; the switch clips into the breaker's accessory slot and becomes mechanically ganged with the operating mechanism. The changeover contacts (one normally-open, one normally-closed, common) are wired to the control circuit via the screw terminals. The surge voltage resistance of 4 kV confirms coordination with standard 400 VAC distribution systems.","metaTitle":"Siemens SENTRON 3VA9978-0AA11 Auxiliary Switch, 10 A Thermal","metaDescription":"Siemens SENTRON 3VA9978-0AA11 auxiliary switch with changeover contacts for 3VA4/5/6 breakers. 10 A thermal current, AC-15/DC-13 ratings. Current production. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Breaker Accessories"],"specifications":{"Maximum":"14","Minimum":"19","Accessories":"Auxiliary switch","Stripped Length":"15 mm","Thermal Current":"10 A","lifecycle_stage":"current","Product Brand Name":"SENTRON","at AC-12 / at 12 V":"10 A","at AC-12 / at 24 V":"10 A","at AC-12 / at 48 V":"10 A","at AC-15 / at 12 V":"6 A","at AC-15 / at 24 V":"6 A","at AC-15 / at 48 V":"6 A","at DC-12 / at 12 V":"6 A","at DC-12 / at 24 V":"6 A","at DC-12 / at 48 V":"2 A","at DC-13 / at 12 V":"3 A","at DC-13 / at 24 V":"3 A","at DC-13 / at 48 V":"0.8 A","Degree Of Pollution":"3","Product Designation":"auxiliary switch","at AC-12 / at 125 V":"10 A","at AC-12 / at 400 V":"6 A","at AC-12 / at 600 V":"2 A","at AC-15 / at 125 V":"6 A","at AC-15 / at 600 V":"0.6 A","at DC-12 / at 110 V":"0.6 A","at DC-12 / at 250 V":"0.3 A","at DC-13 / at 110 V":"0.2 A","at DC-13 / at 250 V":"0.1 A","Overvoltage Category":"III","Stripped Length [In]":"0.6 in","Design Of The Product":"Accessories for 3VA circuit breakers","at AC-12 / at 220/240 V":"10 A","at AC-12 / at 380/400 V":"6 A","at AC-15 / at 220/240 V":"6 A","at AC-15 / at 380/400 V":"2 A","Surge Voltage Resistance":"4 kV","operating voltage / at DC / rated value / minimum":"250 V"}},"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=650502&mlfb=3VA9978-0AA11","alternativesUrl":"https://aoctrl.com/api/mcp/products/3VA9978-0AA11/alternatives.json"},"ai":{"faq":[{"question":"What is 3VA9978-0AA11's listed maximum (14) on this component line?","answer":"The value 14 refers to the housing width in millimeters — the switch occupies a 14 mm module slot on the DIN rail, matching the per-pole width of the host 3VA breaker."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3VA9978-0AA11","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/3VA9978-0AA11 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}}