Square D MH36300 I-Line Circuit Breaker

Square D MH36300 is a three-pole, 300-amp molded-case circuit breaker built for I-Line panelboards. Rated for up to 600 VAC three-phase service, it provides dependable overcurrent protection in commercial and industrial electrical distributions. As part of the MH family, this plug-in breaker uses thermal-magnetic trip technology with distinct long-time and instantaneous trip functions to protect conductors and equipment from overloads and short circuits. The I-Line mounting style enables direct, space-saving installation into compatible Square D I-Line panels, with ABC phase connections standard for three-phase circuits. Designed for rugged use in demanding environments, MH36300 breakers are commonly employed as main or feeder protection within Square D panelboards that combine I-Line sections with other bus styles, offering a streamlined solution for distributing power to downstream equipment. With its 3P configuration and solid molded-case construction, the MH36300 delivers straightforward replacement in legacy Square D installations and aligns with existing I-Line accessory ecosystems, simplifying maintenance and future upgrades for industrial electrical infrastructure.