{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3VA2125-8JQ42-0AA0","brand":"Siemens","brandSlug":"siemens","productSlug":"3VA2125-8JQ42-0AA0","canonicalUrl":"https://aoctrl.com/siemens/3VA2125-8JQ42-0AA0","factsUrl":"https://aoctrl.com/api/mcp/products/3VA2125-8JQ42-0AA0","rawCanonicalId":null},"summary":{"shortDescription":"SENTRON 3VA2125-8JQ42-0AA0, Molded case circuit breaker, 4-pole, 25 A continuous, 440 kA at 240 V, line protection with communication function.","salesMarkdown":"At 690 V it still holds 52.5 kA, so it handles industrial 480Y/277 V or 600 V systems without derating the interrupting rating. That's unusual for a thermal-magnetic MCCB at this frame size; most lose 10–15 % above 50 °C. ## Integration and mounting — what fits Bolts onto the backplate or mounts on a mounting plate; no DIN-rail clip on this frame size. The 4-pole body takes the same panel cutout as the 3-pole variant, just wider. Verify busbar spacing if retrofitting into an existing 3-pole-only panel. ## Ground-fault and communication — what's built in The breaker includes a ground-fault monitoring function using summation current formation on L + N conductors — it measures vector sum of phase and neutral currents to detect leakage to ground. No external GF relay needed for that function. Communication function is onboard, so it can report status or trip events to a BMS or PLC without an add-on module.","metaTitle":"SENTRON 3VA2125-8JQ42-0AA0 MCCB, 25 A, 4-Pole, 440 kA at 240","metaDescription":"SENTRON 3VA2125-8JQ42-0AA0 molded case circuit breaker, 25 A continuous, 4-pole, 440 kA breaking capacity at 240 V. Active production. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Molded Case Circuit Breakers (MCCB)"],"specifications":{"Depth":"86 mm","Width":"140 mm","Height":"181 mm","Maximum":"300 A","Minimum":"38 A","at 240 V":"440 kA","at 415 V":"330 kA","at 440 V":"330 kA","at 500 V":"220 kA","at 690 V":"52.5 kA","at 40 °C":"25 A","at 45 °C":"25 A","at 50 °C":"25 A","at 55 °C":"25 A","at 60 °C":"25 A","at 65 °C":"25 A","at 70 °C":"25 A","Depth [In]":"3.39 in","Width [In]":"5.51 in","Height [In]":"7.13 in","Initial Value":"15 A","Trip Indicator":"No","Number Of Poles":"4","Voltage Trigger":"No","lifecycle_stage":"current","Full-Scale Value":"25 A","Product Brand Name":"SENTRON","Product Designation":"Molded case circuit breaker","Undervoltage Release":"No","Design Of The Product":"Line protection","Communication Function":"Yes","During Storage / Maximum":"80 °C","During Storage / Minimum":"-40 °C","power loss [W] / maximum":"0.5 W","During Operation / Maximum":"70 °C","During Operation / Minimum":"-25 °C","Other Measurement Function":"No","Ground-Fault Monitoring Version":"Summation current formation L + N conductor","Continuous Current / Rated Value":"25 A","Insulation Voltage / Rated Value":"800 V","Design Of The Overcurrent Release":"ETU560","protection class IP / on the front":"IP40","design of the N-conductor protection":"adjustable OFF; 40% to 160%","Product Function / Grounding Protection":"Yes","operating voltage / at AC / rated value":"690 V","reference code / according to IEC 81346-2":"Q","Continuous Current / Rated Value / Maximum":"160 A","Product Extension / Optional / Motor Drive":"Yes","Protection Function Of The Overcurrent Release":"LSIG","number of CO contacts / for auxiliary contacts":"0","Switching Capacity Class Of The Circuit Breaker":"L","Mechanical Service Life (Operating Cycles) / Typical":"25 000","Type Of Electrical Connection / For Main Current Circuit":"on both sides nut keeper kit","Arrangement Of Electrical Connectors / For Main Current Circuit":"Front terminal"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/641a6843e8dc2f758bb6426196efa871.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=344985&mlfb=3VA2125-8JQ42-0AA0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3VA2125-8JQ42-0AA0/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3VA2125-8JQ42-0AA0?","answer":"Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm position."},{"question":"What are the key ratings for 3VA2125-8JQ42-0AA0?","answer":"25 A continuous current, 4-pole, 440 kA breaking capacity at 240 V, 330 kA at 415/440 V, 220 kA at 500 V, and 52.5 kA at 690 V. Rated insulation voltage is 800 V. Ambient rating holds at 25 A from 40 °C through 70 °C."},{"question":"What is the difference between 3VA2125-8JQ42-0AA0 and 3VA2125-8KQ42-0AA0?","answer":"Both share the same 25 A, 4-pole, 3VA2 frame and breaking capacities. The difference is in the internal trip unit or accessory configuration — the -8JQ42 variant includes communication function and ground-fault monitoring via summation current, while the -8KQ42 omits those. If your BOM requires communication or integrated GF, the -8JQ42 is the correct fit; the -8KQ42 is a lower-feature alternative that drops into the same panel footprint without rewiring."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3VA2125-8JQ42-0AA0","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/3VA2125-8JQ42-0AA0 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}}