Eaton KD3125Y - 125 A, 600 V, 3-Pole Bolt-On Circuit Breaker | AmpState

Engineered by Eaton, the KD3125Y is a 125 A, 600 V, 3-pole bolt-on molded case circuit breaker designed to protect branch circuits with precision in panelboards and load centers. Built for rugged reliability, it excels in residential, commercial, and light industrial environments where consistent protection and dependable operation matter most.

Key advantages

• Bolt-on mounting delivers a rigid, vibration-resistant bus connection, reducing wear and ensuring stable current flow over time.
• Thermal-magnetic trip unit provides stable, repeatable protection—responding to both overcurrent and short-circuit conditions with predictable behavior.
• OEM compatibility designed to integrate seamlessly with matching Eaton OEM load centers and panelboards for streamlined installation and maintenance.
• Flexible 3-pole protection ideal for 3-phase distribution in commercial and light industrial settings, while also suitable for complex residential panel configurations when 3-phase is present.

Ideal applications

• Primary protection in electrical panelboards and load centers where reliable overcurrent and short-circuit protection is essential.
• New installations and OEM replacements in residential, commercial, and light industrial projects requiring a robust 3-pole solution.
• Panel upgrades or expansions that demand a bolt-on molded case breaker with strong bus connection and predictable trip behavior.

Technical snapshot

• Manufacturer: Eaton
• Part number: KD3125Y
• Type: Thermal-magnetic molded case circuit breaker
• Amperage rating: 125 A
• Voltage rating: 600 V
• Number of poles: 3
• Mounting style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Why this breaker stands out

• Durability in harsh environments thanks to a bolt-on design that secures a tight, low-resistance connection to the bus bars, minimizing thermal stress during surge events.
• Predictable protection curve with a thermal-magnetic mechanism, reducing nuisance trips while delivering quick response to genuine faults.
• Clear path to reliable performance in panelboards and load centers that require exacting compatibility with Eaton OEM equipment.
• Versatility across applications—from compact residential panels to light industrial distribution—without compromising protection or ease of installation.

Whether you're upgrading an existing panel or specifying gear for a new installation, the Eaton KD3125Y delivers focused, long-lasting protection for your 3-phase distribution needs. Its combination of secure bolt-on mounting, stable thermal-magnetic protection, and OEM-compatible design makes it a practical, trustworthy choice for safeguarding electrical systems.