Square D MH36300 - 300 A, 3-Pole Plug-In Circuit Breaker | AmpState

The Square D MH36300 is a 300A, 3‑pole plug‑in molded case circuit breaker engineered for dependable branch circuit overcurrent and short‑circuit protection in panelboards and load centers. Built to simplify service and upgrades, it delivers robust protection where it matters most—across residential, commercial, and light industrial applications.

Why this MH36300 stands out

• Fast plug-in connection for quick installation and streamlined replacements, reducing downtime during upgrades or service calls.
• Thermal‑magnetic trip unit provides stable, repeatable protection performance, responding to overloads with the thermal element and delivering instantaneous action for short circuits via the magnetic element.
• 3‑pole, 300A rating suited for three‑phase systems and high current branch circuits, delivering reliable protection for demanding loads.
• OEM compatibility designed to work with matching Square D OEM load centers and panelboards, ensuring proper coordination and fitment.
• Versatile installation plug‑in mounting supports a wide range of panelboard configurations, making it a practical choice for both new builds and panel upgrades.
• Ideal for multiple sectors from homes and small businesses to light industrial facilities that require solid, code‑compliant protection.

What problems it solves

• Eliminates lengthy wiring work with a plug‑in design, accelerating maintenance and replacements.
• Provides dependable protection against overloads and short circuits, helping prevent equipment damage and electrical fires.
• Ensures system protection remains coordinated with OEM panelboards, reducing compatibility concerns during upgrades.
• Supports high‑demand applications where a 300A, three‑pole solution is required for safe, continuous operation.

Who this is ideal for

• Facilities updating or expanding panelboards or load centers that require a 300A, 3‑pole plug‑in breaker.
• Electrical professionals performing retrofits in residential, commercial, or light industrial settings.
• Projects needing reliable, repeatable thermal‑magnetic protection with quick replacement capabilities.

Technical specifications

• Manufacturer: Square D
• Part Number: MH36300
• Type: Thermal‑magnetic molded case circuit breaker
• Amperage Rating: 300A
• Number of Poles: 3
• Mounting Style: Plug‑in
• Application: Branch circuit overcurrent and short‑circuit protection

Usage tips and best practices

• Verify compatibility with your panelboard or load center’s rated frame and bus configuration before installation.
• When servicing, consider the plug‑in design to minimize downtime—have a replacement breaker ready for a quick swap.
• Use as part of a coordinated protection scheme to ensure consistent trip characteristics across all circuit protections in the system.