LAP36300MB - 300 Amp Circuit Breaker

LAP36300MB - 300 Amp Circuit Breaker

Get dependable protection for your power distribution systems with the LAP36300MB 300-amp circuit breaker from Square D. Designed for demanding industrial and commercial use, this three-pole, thermal-magnetic breaker operates at up to 600 VAC (22 kA interrupting capacity) and 250 VDC (10 kA), giving you the flexibility to deploy in AC or DC environments. Its “MB” short-handle design makes it ideal where panel space is tight—yet it still delivers full performance and safety features. Whether you're safeguarding motors, HVAC systems, or main feeders, this breaker brings performance and compliance together in one package.

Key Features and Benefits

• High current capacity (300 A): Suited for large loads and main feeders.
• Universal voltage rating: 600 VAC (22 kA) and 250 VDC (10 kA) ensure wide application range.
• Three-pole design: Protects all phases in three-phase systems.
• Thermal-magnetic trip unit: Fast response to overloads and short circuits.
• Push-to-Trip button: Lets you manually test the trip mechanism safely without exposing live parts.
• Short (compact) handle version (“MB”): Enables installation in tight panel layouts and allows panel doors to close.
• HACR rated: Ready for HVAC and refrigeration circuits.
• Compliance with environmental standards (RoHS, REACh): Ensures safer materials and lower regulatory risk.

Technical Specifications

• Rated Current: 300 A
• Number of Poles: 3
• Voltage Rating: 600 VAC (22 kA), 250 VDC (10 kA)
• Trip Technology: Thermal + Magnetic
• Mounting Mode: Unit-mount, bolt-on compatible
• Connection Type: Lugs on OFF-end (line side)
• Dimensions (H × W × D): 11.00″ × 6.00″ × 5.84″ (279.4 mm × 152.4 mm × 148.34 mm)
• Weight: 15.72 lb (7.13 kg)
• Standards & Certifications: UL 489, CSA, IEC (per manufacturer documentation)

Material Compliance and Certifications

• RoHS and REACh Compliance: The LAP36300MB is engineered in line with strict environmental and safety standards. It is RoHS- and REACh-compliant, meaning it is free from many hazardous substances like mercury and lead.
• Halogen-Free and PVC-Free: Its plastic components are halogen-free and PVC-free, making it safer over long-term use.
• Certifications: The breaker also carries recognized certifications across UL, CSA, and IEC standards. In many markets, it aligns with “green” product expectations and helps you demonstrate compliance in regulated installations.

Where It Works Best

• This breaker is a top choice in commercial buildings, factories, data centers, and HVAC plants—anywhere you need reliable 300 A protection across three phases. Because it’s HACR-rated, it's especially well suited for heating, ventilation, air conditioning, and refrigeration circuits. Its short-handle design is ideal when panel space is limited or when you must maintain clearance for panel doors. Use it for main switchgear lines, motor feeders, or as a dependable safety device in your power distribution setup.