{"product_id":"siemens-ed21b040l-40a-120v-1-pole-bolt-on-circuit-breaker","title":"Siemens ED21B040L - 40 A, 120 V, 1-Pole Bolt-On Circuit Breaker | AmpState","description":"\u003cdiv\u003e\n\u003cp\u003eSiemens ED21B040L is a rugged 40A, 120V, 1-pole bolt-on molded case circuit breaker engineered for dependable branch circuit protection in panelboards and loadcenters. This unit delivers reliable overcurrent and short-circuit protection for residential, commercial, and light industrial electrical setups, making it a solid choice for upgrades, retrofits, or new installations.\u003c\/p\u003e \u003cul\u003e \u003cli\u003e\n\u003cstrong\u003eSecure bolt-on mounting\u003c\/strong\u003e provides a rigid, vibration-resistant bus connection, reducing loosening risks in environments with movement or vibration.\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eThermal-magnetic trip unit\u003c\/strong\u003e combines precise thermal overload sensing with instantaneous magnetic trip for fast, repeatable protection against both gradual overheating and sudden fault conditions.\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003ePlug-free reliability\u003c\/strong\u003e designed for use with matching OEM Siemens loadcenters and panelboards, ensuring proper fit and predictable performance within your system.\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eVersatile, all-purpose protection\u003c\/strong\u003e suitable for a wide range of applications—from lighting and receptacle circuits to HVAC and small equipment feeders—without compromising safety.\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eDurable molded-case construction\u003c\/strong\u003e built to withstand daily electrical demand and maintain consistent protection over time.\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch3\u003eIdeal use cases\u003c\/h3\u003e\n\u003cul\u003e \u003cli\u003eResidential panel upgrades where a dedicated 40A, 120V protection device is required for branch circuits.\u003c\/li\u003e \u003cli\u003eCommercial settings needing reliable protection for lighting, outlets, or small equipment feeders in loadcenters.\u003c\/li\u003e \u003cli\u003eLight industrial applications with vibration or movement where a secure bolt-on connection minimizes nuisance trips and loosening.\u003c\/li\u003e \u003cli\u003eNew installations or retrofits that call for Siemens-approved compatibility with OEM panelboards and modular breakers.\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch3\u003eWhat problems does this solve?\u003c\/h3\u003e\n\u003cul\u003e \u003cli\u003ePrevents fire hazards and equipment damage by swiftly interrupting fault currents and preventing overheated conductors.\u003c\/li\u003e \u003cli\u003eReduces maintenance concerns in installations subject to vibration or mechanical stress due to its secure mounting.\u003c\/li\u003e \u003cli\u003eProvides predictable, repeatable protection—so you can design circuits with confidence and coordination.\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch3\u003eTechnical snapshot\u003c\/h3\u003e\n\u003cul\u003e \u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Siemens\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e ED21B040L\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 40A\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eVoltage rating:\u003c\/strong\u003e 120V\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eNumber of poles:\u003c\/strong\u003e 1\u003c\/li\u003e \u003cli\u003e\n\u003cstrong\u003eMounting style:\u003c\/strong\u003e Bolt-on\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 \u003cp\u003eChoose this Siemens ED21B040L for a dependable, OEM-compatible protection solution that pairs robust physical mounting with precise electrical protection. Available from AmpState for straightforward procurement and confident performance in your panelboards and loadcenters.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Amp State","offers":[{"title":"Default Title","offer_id":46349784842402,"sku":null,"price":710.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0666\/8094\/6850\/files\/siemens_breaker_and_panel_6776423c-7edd-4fc2-89e8-287451400e0a.png?v=1764156617","url":"https:\/\/www.ampstate.com\/products\/siemens-ed21b040l-40a-120v-1-pole-bolt-on-circuit-breaker","provider":"Ampstate Electric Corporation","version":"1.0","type":"link"}