Square D FH16040B - 40 A, 1-Pole Plug-In Circuit Breaker | AmpState

Engineered for dependable protection and quick service, the Square D FH16040B is a 40A, 1-pole plug-in molded case circuit breaker designed to safeguard your electrical system in panelboards and load centers. Built for fast installation and straightforward replacement, it keeps critical circuits powered while minimizing downtime during upgrades or maintenance.

Why the FH16040B stands out

• Fast plug-in connection for hassle-free installation and rapid swap-out when servicing or upgrading panelboards.
• Thermal-magnetic trip unit delivers stable, repeatable protection against overcurrent and short-circuit events, helping to prevent nuisance trips and protect connected equipment.
• OEM-compatible design works with matching Square D load centers and panelboards, ensuring reliable fit and performance.
• Versatile application suitable for residential, commercial, and light industrial electrical systems that require dependable branch-circuit protection.

Technical snapshot

• Manufacturer: Square D
• Part Number: FH16040B
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 40A
• Number of Poles: 1
• Mounting Style: Plug-in
• Application: Branch circuit overcurrent and short-circuit protection

Ideal use cases

Install the FH16040B in residential panels to protect lighting circuits, receptacle banks, or dedicated equipment runs. In commercial settings, it safeguards small electrical subsystems in offices, retail spaces, or service areas. For light industrial environments, it provides reliable protection for machines or charging stations where a fast-reacting, plug-in solution is advantageous.

What problems does it solve?

• Provides reliable overcurrent protection to prevent wiring damage and equipment failure from short circuits or overloads.
• Enables quick maintenance with a plug-in design, reducing panel downtime during replacement or upgrades.
• Delivers predictable trip behavior through its thermal-magnetic mechanism, balancing time-delay response with magnetic instantaneous protection.

Tips for optimal use

• Verify compatibility with your OEM Square D load centers and panelboards before installation to ensure a seamless fit.
• Use as a dedicated protection device for circuits rated near 40A to maximize safety for high-draw loads and avoid nuisance trips from inrush currents.
• Schedule routine panel inspections and replace any breaker that shows signs of wear, overheating, or damage to the terminations.

Whether you’re upgrading an aging panel, stocking a parts inventory, or performing routine electrical maintenance, the Square D FH16040B 40A, 1-pole plug-in circuit breaker delivers dependable protection, quick service, and broad compatibility for a wide range of panels and applications.