{"product_id":"square-d-qo390-90a-240v-3-pole-plug-in-circuit-breaker","title":"Square D QO390 - 90 A, 240 V, 3-Pole Plug-In Circuit Breaker | AmpState","description":"\u003cdiv\u003e\n\u003cp\u003eWhen you need dependable protection for 240V circuits, the Square D QO390 delivers precisely what you require. This 90A, 240V, 3-pole plug-in molded case circuit breaker is built for quick installation in panelboards and load centers, providing reliable overcurrent and short-circuit protection for residential, commercial, and light industrial applications.\u003c\/p\u003e \u003ch3\u003eWhat makes the QO390 stand out\u003c\/h3\u003e \u003cul\u003e \u003cli\u003e\n\u003cstrong\u003eFast plug-in connection:\u003c\/strong\u003e streamlined installation and painless replacement minimizes downtime during panel upgrades or servicing.\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eThermal-magnetic trip unit:\u003c\/strong\u003e provides stable, repeatable protection across loads and temperatures by combining thermal overload sensing with magnetic short-circuit detection.\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eOEM-compatible compatibility:\u003c\/strong\u003e designed to work with matching Square D QO panelboards and load centers for a safe, code-compliant fit.\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eThree-pole, 90A, 240V configuration:\u003c\/strong\u003e robust protection for 3-wire circuits and balanced loads in 240V systems, suitable for multi-pole applications.\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003ePlug-in mounting:\u003c\/strong\u003e drop-in style that simplifies installation and future servicing without lugs or bolts.\u003c\/li\u003e\n\u003c\/ul\u003e \u003cp\u003e\u003cstrong\u003eTechnical snapshot\u003c\/strong\u003e\u003c\/p\u003e \u003cul\u003e \u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Square D\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e QO390\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Thermal-magnetic molded case circuit breaker\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eAmperage Rating:\u003c\/strong\u003e 90A\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eVoltage Rating:\u003c\/strong\u003e 240V\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eNumber of Poles:\u003c\/strong\u003e 3\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eMounting Style:\u003c\/strong\u003e Plug-in\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eApplication:\u003c\/strong\u003e Branch circuit overcurrent and short-circuit protection\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch4\u003eIdeal use cases\u003c\/h4\u003e \u003cul\u003e \u003cli\u003eResidential panel upgrades and service panels needing reliable 90A protection on 240V circuits.\u003c\/li\u003e \u003cli\u003eCommercial panels in small to mid-size facilities requiring quick-replace, plug-in breakers for routine maintenance.\u003c\/li\u003e \u003cli\u003eLight industrial setups with multi-wire branch circuits where fast swap-in protection minimizes downtime.\u003c\/li\u003e\n\u003c\/ul\u003e \u003cp\u003eThe QO390 doesn’t just protect equipment—it helps keep your electrical system safe, compliant, and running smoothly. With a rapid plug-in connection, a dependable thermal-magnetic trip, and compatibility with Square D QO panelboards, it’s a practical, long-term choice for ongoing electrical reliability. Choose AmpState for genuine Square D components and prompt, knowledgeable support for your panel upgrades and replacements.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Amp State","offers":[{"title":"Default Title","offer_id":46355405602978,"sku":null,"price":710.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0666\/8094\/6850\/files\/schnieder_and_square_d_breaker_and_panel_83ecf0a3-4c10-4e34-9289-4636ad9cae32.png?v=1764691877","url":"https:\/\/www.ampstate.com\/products\/square-d-qo390-90a-240v-3-pole-plug-in-circuit-breaker","provider":"Ampstate Electric Corporation","version":"1.0","type":"link"}