{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3VA9978-0BA21","brand":"Siemens","brandSlug":"siemens","productSlug":"3VA9978-0BA21","canonicalUrl":"https://aoctrl.com/siemens/3VA9978-0BA21","factsUrl":"https://aoctrl.com/api/mcp/products/3VA9978-0BA21","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON shunt trip, 48-60 VAC 50/60 Hz, auxiliary release accessory for 3VA4 and 3VA5/3VA6 breakers, 31.2 mm depth, 3 slots.","salesMarkdown":"The Siemens 3VA9978-0BA21 is a SENTRON-brand shunt trip (auxiliary release) for the 3VA4 and 3VA51 through 3VA64 molded-case breaker family. It trips the breaker remotely when you apply 48 to 60 VAC at 50/60 Hz — no DC variant here, so keep the supply AC. It draws up to 670 VA apparent power on trip, so size your control transformer accordingly. This shunt trip measures 31.2 mm deep by 21.7 mm wide and 65.1 mm tall — it tucks into the accessory slot on the breaker without stealing DIN-rail space. It occupies three slots inside the breaker accessory bay. Wire stripping length is 10 mm (0.4 in), so trim your ferruled leads to that and no whiskers. The form factor is specific to the 3VA4 and 3VA5/3VA6 frames; it won't drop into a 5SY miniature breaker panel without rewiring, because those use a completely different accessory interface.","metaTitle":"Siemens 3VA9978-0BA21 Shunt Trip, 48-60 VAC, SENTRON","metaDescription":"Siemens 3VA9978-0BA21 SENTRON shunt trip accessory for 3VA4/3VA5/3VA6 breakers. 48-60 VAC, 50/60 Hz, 31.2 mm deep. Active production. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Breaker Accessories"],"specifications":{"Depth":"31.2 mm","Width":"21.7 mm","title":"3VA9978-0BA21","Height":"65.1 mm","Maximum":"16","Minimum":"20","Accessories":"Auxiliary release","description":"SHUNT TRIP FLEXIBLE 48-60 V AC 50/60 HZ ACCESSORY FOR 3VA4 and 3VA51 up to 3VA54 and 3VA61 up to 3VA64","Number of slots":"3","Product version":"Auxiliary release","lifecycle_stage":"current","Product brand name":"SENTRON","Degree of pollution":"3","Product designation":"Accessories","Overvoltage category":"III","Wire stripping length":"10 mm","Surge voltage resistance":"4 kV","Wire stripping length [in]":"0.4 in","Rated insulation voltage Ui":"690 V","Apparent power consumption / maximum":"670 V·A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/4f486c1d5f65fbe592ca0422c1a96a05.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=650514&mlfb=3VA9978-0BA21"},"ai":{"faq":[{"question":"What is the closest functional second-source — 5SY4140-7?","answer":"The 5SY4140-7 is a SENTRON miniature circuit breaker, not a shunt trip — it's a different product class entirely. The 3VA9978-0BA21 is an accessory for 3VA4 and 3VA5/3VA6 molded-case breakers and won't interchange with any 5SY-series part without rewiring the panel. There's no direct functional second-source; the only fit is within the 3VA family it was designed for."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3VA9978-0BA21","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/3VA9978-0BA21 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:47:38.189Z","lastPublished":"2026-07-22T19:47:38.189Z","indexable":true}}