Commander 40 Amp Circuit Breaker QBH340 - 40 A Circuit Breaker | AmpState

Meet the Commander QBH340 40 Amp Circuit Breaker—a molded case breaker purpose-built for dependable branch circuit overcurrent and short-circuit protection in panelboards and loadcenters. Its compact design helps you maximize panel space without sacrificing protection, making it an ideal choice for streamlined, reliable electrical installations in a wide range of settings.

Key features that matter in the real world

• Compact molded case design saves panel space and simplifies layout, allowing more room for essential circuits in tight panels.
• Thermal-magnetic trip unit delivers stable, repeatable protection by combining overload sensing with fast short-circuit response, reducing nuisance trips and safeguarding downstream wiring.
• 40 Ampere rating (40A) provides solid protection for typical residential branch circuits, as well as light commercial and industrial applications.
• OEM compatibility is designed to work with matching OEM loadcenters and panelboards for straightforward replacement and seamless integration.
• Versatile application suitable for residential, commercial, and light industrial environments, accommodating a variety of load profiles and duty cycles.

Technical snapshot

• Part Number: QBH340
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 40A
• Application: Branch circuit overcurrent and short-circuit protection
• Manufacturer: Commander

Ideal uses and real-world scenarios

• Replacing a blown or unreliable 40A breaker in existing panelboards or loadcenters to restore reliable protection for a dedicated circuit (e.g., HVAC, ovens, water heaters, or subpanels).
• Upgrading panel protection in small offices, retail spaces, or light manufacturing where compact form factors save space without compromising safety.
• New installations where OEM compatibility with the panelboard family ensures a smooth, hassle-free setup and faster commissioning.
• Maintenance projects that require a dependable, repeatable trip response across varying temperatures and electrical loads.

Why this breaker stands out

While there are many options, the QBH340’s combination of a compact molded case design and a thermal-magnetic trip unit provides two essential advantages: efficient use of panel space and precise protection that minimizes nuisance trips on moderate fault conditions. Its OEM-compatible architecture means you can swap in confidently for the intended panelboards and loadcenters without additional adapters or kits, preserving the integrity of your electrical system.

Practical tips for best results

• Verify that your panelboard or loadcenter is listed as compatible with the QBH340 series to ensure a seamless fit and reliable operation.
• When installing, follow manufacturer guidelines for mounting orientation and termination torque to maintain the integrity of the connection and protection characteristics.
• Keep a spare QBH340 on hand for quick replacements in routine service outages, reducing downtime on critical circuits.
• Match the breaker rating to the protected circuit’s ampacity and conductor size to maintain proper protection coordination and prevent mis-tripping.

In summary, the Commander QBH340 40A circuit breaker delivers space-efficient protection, reliable thermal-magnetic performance, and OEM-friendly compatibility—an excellent choice for professionals and seasoned DIYers looking to safeguard circuits in panelboards and loadcenters with confidence.