{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3VA2125-5KP42-0AA0","brand":"Siemens","brandSlug":"siemens","productSlug":"3VA2125-5KP42-0AA0","canonicalUrl":"https://aoctrl.com/siemens/3VA2125-5KP42-0AA0","factsUrl":"https://aoctrl.com/api/mcp/products/3VA2125-5KP42-0AA0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 3VA2125-5KP42-0AA0, molded case circuit breaker, 4-pole, 25 A continuous, ETU850 electronic trip unit, 187 kA interrupting at 240 V, IP40 front, current lifecycle.","salesMarkdown":"The Siemens SENTRON 3VA2125-5KP42-0AA0 is a 4-pole molded case circuit breaker rated 25 A continuous, built around the ETU850 electronic trip unit. It's a line-protection design, meaning it sits at the feeder or sub-feed level in a distribution panel, not on a motor branch. The 4-pole configuration handles three-phase plus neutral switching, common in North American and some European schemes where the neutral needs to be disconnected. 187 kA at 240 V is the headline number — that's the short-circuit current this breaker can safely interrupt at 240 VAC, which covers most residential and light commercial service-entrance applications in North America. At 415 V and 440 V it still holds 121 kA, enough for industrial panel feeders. At 690 V it drops to 3.7 kA, so if you're on a 690 V system (some mining or marine plants) this breaker is not the right choice for high-fault locations — you'd need a higher-rated frame. The 3VA2125-5KP42-0AA0 measures 86 mm deep, 140 mm wide, and 181 mm tall. That's a compact footprint for a 4-pole 25 A MCCB with an electronic trip unit and comms — it slides into the same cutout as other 3VA2 frame breakers, so if you're swapping a 3VA2125-8KQ42-0AA0 (different trip unit) the mechanical fit is identical. No re-drilling the panel.","metaTitle":"Siemens SENTRON 3VA2125-5KP42-0AA0 MCCB, 25 A, 4-pole, ETU85","metaDescription":"Siemens SENTRON 3VA2125-5KP42-0AA0 molded case circuit breaker, 25 A continuous, 4-pole, ETU850 trip unit, 187 kA at 240 V. IP40 front. Current lifecycle. Quoted to order.","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":"187 kA","at 415 V":"121 kA","at 440 V":"121 kA","at 500 V":"75.6 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","Trip Indicator":"No","Number Of Poles":"4","Voltage Trigger":"No","lifecycle_stage":"current","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":"0.6 W","During Operation / Maximum":"70 °C","During Operation / Minimum":"-25 °C","Other Measurement Function":"Yes","Ground-Fault Monitoring Version":"Without","Continuous Current / Rated Value":"25 A","Insulation Voltage / Rated Value":"800 V","Design Of The Overcurrent Release":"ETU850","protection class IP / on the front":"IP40","design of the N-conductor protection":"adjustable OFF; 40% to 160%","Product Function / Grounding Protection":"No","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":"LSI","number of CO contacts / for auxiliary contacts":"0","Switching Capacity Class Of The Circuit Breaker":"M","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=392175&mlfb=3VA2125-5KP42-0AA0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3VA2125-5KP42-0AA0/alternatives.json"},"ai":{"faq":[{"question":"Will 3VA2125-5KP42-0AA0 drop into a panel that was specified around 3VA2125-8KQ42-0AA0 without rewiring?","answer":"Yes, the mechanical footprint is identical — same 86 mm depth, 140 mm width, 181 mm height. The difference is the trip unit: the 5KP42 uses an ETU850 with communication function, while the 8KQ42 uses a different release. No panel rework needed for the swap."},{"question":"Where can I buy 3VA2125-5KP42-0AA0?","answer":"This breaker is sourced and quoted to order through independent distribution. Submit an RFQ for current pricing and availability — confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3VA2125-5KP42-0AA0","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/3VA2125-5KP42-0AA0 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}}