{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3VA2125-7HM42-0AA0","brand":"Siemens","brandSlug":"siemens","productSlug":"3VA2125-7HM42-0AA0","canonicalUrl":"https://aoctrl.com/siemens/3VA2125-7HM42-0AA0","factsUrl":"https://aoctrl.com/api/mcp/products/3VA2125-7HM42-0AA0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 3VA2125-7HM42-0AA0, molded case circuit breaker, 4-pole, 25 A continuous, 330 kA interrupting at 240 V, line protection design, ground-fault summation monitoring.","salesMarkdown":"That flat thermal curve means the 25 A rating holds in a hot enclosure; you don't lose headroom as the panel warms up. Ground-fault monitoring uses summation-current sensing on L+N conductors, so it detects leakage without a separate GFCI module — one less device on the DIN rail. ## Interrupting capacity — the real selectivity number The interrupting rating is 330 kA at 240 V, dropping to 242 kA at 415 V and 440 V, 187 kA at 500 V, and 3.7 kA at 690 V. At 690 V the rating drops sharply to 3.7 kA, so this is not a 690 V main breaker; it belongs on a 480 V or lower bus. The adjustable thermal-magnetic trip range spans 38 A minimum to 300 A maximum — note that the 25 A continuous rating is the frame's maximum continuous current; the trip unit itself can be set lower for cable protection. Power loss is 0.6 W maximum, negligible for thermal budget in a dense panel. The 140 mm width is the same as other 4-pole 3VA2 breakers in this frame size, so swapping from a 3VA2025-8HM42-0AA0 or 3VA2125-8KQ42-0AA0 requires no re-drilling or bus-bar rework. No communication function and no undervoltage release — this is a straight thermal-magnetic breaker, no electronics to fail. Trip indicator is absent, so fault status must be read from the handle position. The 25 A continuous rating at 70 °C means it can be packed into a warm panel without derating, which simplifies the fill-factor calculation for the enclosure.","metaTitle":"Siemens 3VA2125-7HM42-0AA0 SENTRON MCCB, 25 A, 4-Pole, 330 k","metaDescription":"Siemens SENTRON 3VA2125-7HM42-0AA0 molded case circuit breaker, 25 A continuous, 4-pole, 330 kA interrupting at 240 V. Current 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":"330 kA","at 415 V":"242 kA","at 440 V":"242 kA","at 500 V":"187 kA","at 690 V":"3.7 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":"No","During Storage / Maximum":"80 °C","During Storage / Minimum":"-40 °C","power loss [W] / maximum":"0.6 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":"ETU330","protection class IP / on the front":"IP40","design of the N-conductor protection":"adjustable OFF; 100%","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":"LIG","number of CO contacts / for auxiliary contacts":"0","Switching Capacity Class Of The Circuit Breaker":"C","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=145913&mlfb=3VA2125-7HM42-0AA0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3VA2125-7HM42-0AA0/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3VA2125-7HM42-0AA0 and how is it quoted?","answer":"Sourced through independent distribution channels. Quoted to order against an RFQ — availability and current pricing confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3VA2125-7HM42-0AA0","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/3VA2125-7HM42-0AA0 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}}