{"product_id":"square-d-q1b3901021-90a-3p-240v-circuit-breaker","title":"Square D Q1B3901021 Circuit Breaker, 90A, 3-Pole, 240V","description":"\u003cdiv\u003e\n\u003cp\u003eMeet the Square D Q1B3901021 circuit breaker—crafted for demanding industrial environments and designed to support service, maintenance, and replacement projects with confidence. This 90A, 3‑pole, 240V unit delivers targeted overcurrent protection where it matters most, and the part number Q1B3901021 is your quickest route to compatibility confirmation for your application.\u003c\/p\u003e \u003ch2\u003eWhy this 3‑pole, 240V breaker stands out\u003c\/h2\u003e\n\u003cp\u003eWhen protecting multi‑phase electrical systems, balanced protection across all conductors is essential. The Q1B3901021 provides reliable 90‑amp, three‑pole protection for 240V circuits, helping prevent damage from overloads and short circuits. Built by Square D, it’s engineered to fit within compatible industrial panels and enclosures, streamlining installation and ongoing maintenance.\u003c\/p\u003e \u003ch2\u003eKey specifications\u003c\/h2\u003e\n\u003cul\u003e \u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Square D\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e Q1B3901021\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Circuit Breaker\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eAmperage:\u003c\/strong\u003e 90 A\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003ePoles:\u003c\/strong\u003e 3\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eVoltage:\u003c\/strong\u003e 240 V\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch2\u003eIdeal applications\u003c\/h2\u003e\n\u003cul\u003e \u003cli\u003eIndustrial service upgrades and panel replacements in manufacturing facilities\u003c\/li\u003e \u003cli\u003eProtection for high‑load machinery and three‑phase equipment on 240V systems\u003c\/li\u003e \u003cli\u003eMaintenance projects where a reliable, compatible Square D breaker is required\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch2\u003eHow to ensure a perfect fit\u003c\/h2\u003e\n\u003cp\u003eVerify fit by the exact part number and alignment with your application requirements. If you’re unsure about compatibility, we can help—send a message and we’ll assist with part number validation and integration considerations.\u003c\/p\u003e \u003ch2\u003ePractical tips for installation and use\u003c\/h2\u003e\n\u003cul\u003e \u003cli\u003eConsult the panel’s documentation to confirm three‑pole, 240V compatibility and any torque specifications for mounting\u003c\/li\u003e \u003cli\u003ePlan replacements during scheduled maintenance to minimize downtime and ensure system protection remains uninterrupted\u003c\/li\u003e \u003cli\u003eKeep the exact part number handy (Q1B3901021) when ordering spares or coordinating with your electrical distributor\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"AmpState","offers":[{"title":"Default Title","offer_id":46415707799714,"sku":"Q1B3901021","price":460.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0666\/8094\/6850\/files\/master_generic_513d6710-3734-4b27-839d-f68e6f4b470a.png?v=1765492974","url":"https:\/\/www.ampstate.com\/products\/square-d-q1b3901021-90a-3p-240v-circuit-breaker","provider":"Ampstate Electric Corporation","version":"1.0","type":"link"}