EATON KD3400NW Molded Case Circuit Breaker

Overview

The EATON KD3400NW is a Series C K‑frame molded case circuit breaker manufactured by EATON. The EATON KD3400NW is a three‑pole 400A MCCB built for branch feeder and motor circuit protection in low‑voltage power distribution systems. The EATON KD3400NW supports thermal‑magnetic trip units or interchangeable Digitrip electronic trip units, delivering overload, short‑circuit and optional ground fault protection. The EATON KD3400NW is widely stocked as spare protection component for industrial panels, commercial power rooms and marine distribution cabinets. It is rated for 600 Vac and 250 Vdc, offering reliable fault interruption for 50/60 Hz power networks.

Features

The EATON KD3400NW adopts the K‑frame mechanical platform of EATON Series C, with interchangeable trip modules to match different protection requirements. The EATON KD3400NW can be configured with fixed thermal‑magnetic trip or adjustable Digitrip OPTIM electronic trip, supporting zone selective interlocking and arc flash reduction maintenance mode when fitted with 310+ trip units. The EATON KD3400NW provides high short‑circuit interrupting capacity, 65 kAIC at 240 Vac and 35 kAIC at 480 Vac. Auxiliary contacts, alarm switches and shunt trip accessories are available for remote control and SCADA status feedback. The EATON KD3400NW complies with UL 489 standards and is suitable for both indoor industrial and marine applications. The terminal layout and mounting footprint of the EATON KD3400NW enable direct replacement for other KD series K‑frame breakers.

Specs

Device Type: Molded Case Circuit Breaker (MCCB) Model: EATON KD3400NW Series: Series C, K‑frame Poles: 3‑pole Continuous Current: 400 A Voltage Rating: 600 Vac, 250 Vdc Frequency: 50 / 60 Hz Interrupt Rating: 65 kAIC @ 240 Vac, 35 kAIC @ 480 Vac Trip Options: Thermal‑magnetic / Digitrip OPTIM electronic trip Certification: UL 489 Listed Mounting: Panel mount Protection Grade: IP20 inside switchgear cabinet Operating Temperature: -20°C ~ +60°C

Principle

The EATON KD3400NW samples current through internal sensing elements. For thermal‑magnetic versions, the bimetallic element responds to overload current and the magnetic coil triggers instantaneous short‑circuit tripping. When equipped with an electronic Digitrip unit, the EATON KD3400NW calculates current values digitally and executes configurable protection curves, including zone selective interlocking to coordinate upstream and downstream breakers. Once a fault is detected, the internal mechanism opens the main contacts to isolate the faulty circuit.

Applications

The EATON KD3400NW is used for feeder protection, motor protection and distribution branch protection in factories, water treatment plants, commercial buildings and marine power panels. The EATON KD3400NW is stocked as spare part for emergency replacement and scheduled maintenance of existing EATON Series C MCCB systems. It also supports power distribution cabinet renovation and protection coordination projects.