Eaton HKD3400K - 400 A, 600 V, 3-Pole Circuit Breaker | AmpState

The Eaton HKD3400K is a 400 A, 600 V, 3-pole molded case circuit breaker (MCCB) engineered to safeguard panelboards and load centers with reliable branch circuit overcurrent and short-circuit protection. Built to perform in everyday commercial spaces and light industrial environments, it delivers robust protection without sacrificing panel space.

What makes the HKD3400K stand out

• Compact molded-case design minimizes footprint inside the panel, freeing up space for wiring and future expansion while keeping installation neat and accessible.
• Thermal-magnetic trip unit provides stable, repeatable protection—the thermal element handles sustained overloads, while the magnetic element delivers a fast, decisive response to short circuits.
• 3-pole configuration ideal for 3-phase systems, making it a solid choice for commercial distributions and light industrial applications.
• 400 A / 600 V rating ready for main feeder protection or large branch-circuit protection in modern panels and load centers.
• OEM compatibility designed to align with matching Eaton OEM load centers and panelboards for streamlined replacements and confident, compliant upgrades.

Ideal use cases

• New installations and retrofit projects in panelboards and load centers where space is at a premium but protection cannot be compromised.
• Main feeder protection and large branch circuits in commercial electrical distributions and light industrial panels.
• Replacement or upgrade in existing Eaton systems where compatibility with OEM chassis reduces installation time and risk.

Specifications at a glance

• Manufacturer: Eaton
• Part Number: HKD3400K
• Type: Thermal-magnetic molded case circuit breaker (MCCB)
• Amperage Rating: 400 A
• Voltage Rating: 600 V
• Poles: 3
• Application: Branch circuit overcurrent and short-circuit protection

With the HKD3400K, electricians and facilities managers gain a dependable protection device that aligns with Eaton’s panel and load center ecosystems, simplifying installation, maintenance, and future expansions. By combining a compact form, a precise thermal-magnetic trip mechanism, and OEM-aligned compatibility, this breaker helps keep electrical systems safer, more reliable, and easier to spec across diverse environments.