Eaton HFD1040L - 40 A, 277 V, 1-Pole Circuit Breaker | AmpState

The Eaton HFD1040L is a compact 40A, 277V, 1-pole molded-case circuit breaker designed to shield your electrical system from overcurrent and short-circuit events. Its streamlined profile helps maximize available space inside panelboards and loadcenters, making it a practical choice for tighter electrical layouts without sacrificing protection.

Key protection you can rely on is provided by a thermal-magnetic trip unit, delivering stable, repeatable performance across a range of temperatures and load conditions. This means fewer nuisance trips and more consistent circuit safety for your critical lighting, outlets, and small equipment runs.

Designed for seamless compatibility and easy installation, the HFD1040L is engineered to work with matching OEM loadcenters and panelboards. This alignment ensures a predictable fit, reliable electrical contact, and streamlined maintenance when you’re upgrading or stocking spare protection devices for existing systems.

• Amperage / Voltage: 40A at 277V
• Poles: 1-pole
• Type: Thermal-magnetic molded-case circuit breaker
• Manufacturer / Part: Eaton, HFD1040L
• Application: Branch circuit overcurrent and short-circuit protection
• Compatibility: Requires matching OEM loadcenters and panelboards for optimal fit and performance

Who should consider the Eaton HFD1040L? It’s ideal for residential circuits seeking compact protection solutions, commercial panelboards with single-pole branch circuits, and light industrial applications where reliable 277V protection is essential. Use it to guard lighting runs, power outlets, and small machinery connections within single-phase distribution systems where space efficiency and dependable protection matter most.

Compared to broader, less specialized breakers, the HFD1040L delivers a purpose-built combination of space savings, certified compatibility, and precise thermal-magnetic protection. It’s a smart choice for engineers and electricians who value predictable trips, straightforward replacement, and a dependable fit within Eaton-compatible panel ecosystems.

Practical tips for use: confirm that your panelboard calls for a 1-pole 40A, 277V device, and pair the HFD1040L with the exact matching OEM enclosure to maintain warranty and performance. When installing, ensure secure mounting and proper alignment with bus stabs to maintain optimal conductivity and trip accuracy. For service continuity, keep a few spare HFD1040L units on hand for quick replacement in scheduled maintenance windows or during panel upgrades.