Eaton KD3400 - 400 A, 600 V, 3-Pole Circuit Breaker | AmpState

Ideal use cases

• Large residential subpanels feeding heavy-duty circuits (air conditioning, electric heating, water heaters) where 400 A capacity is required.
• Commercial distribution panels handling multiple lighting, receptacle, and small equipment feeders in offices, retail spaces, and service areas.
• Light industrial panels that power machinery or HVAC systems within safe 600 V distribution limits.

Installation and compatibility insights

Choose the KD3400 when you need a high-capacity, three-pole breaker that aligns with Eaton’s loadcenters and panelboards. Verify that the target panel is compatible with this KD-series device and follow standard electrical installation practices, including manufacturer torque specifications and proper seizing/torquing of connections to ensure reliable, long-term performance.

Performance and long-term value

With its combination of a robust 400 A rating, 600 V capability, and a compact footprint, the KD3400 helps you optimize space without compromising protection. The thermal-magnetic trip mechanism provides precise turn-on and trip characteristics that can adapt to both steady loads and fault conditions, supporting safer, more predictable electrical distribution in demanding environments.

In short, the Eaton KD3400 delivers focused, high-capacity protection for critical branch circuits, backed by OEM compatibility and a design that respects panel space and electrical reliability. It’s a purpose-built solution for professionals who demand consistent performance from their distribution panels.