DK3400W - 400Amp Circuit Breaker

DK3400W - 400 Amp Circuit Breaker

When you're dealing with high-demand electrical systems, you don’t have room for uncertainty—you need a breaker that performs every single time. The Eaton DK3400W molded case circuit breaker is built for exactly that kind of environment. Designed as part of Eaton’s trusted Series C line, this 400 amp, three-pole breaker delivers dependable protection against overloads and short circuits while keeping your operations running smoothly.

What makes the DK3400W stand out is its ability to handle serious electrical loads without hesitation. The T186 thermal-magnetic trip unit responds quickly and accurately when conditions go outside safe limits, helping prevent damage to your equipment and reducing the risk of costly downtime. Whether you're upgrading an existing panel or maintaining a critical system, this breaker gives you the confidence that your electrical infrastructure is protected by a proven solution.

Its K-frame construction strikes a smart balance between power and space efficiency, making it easier to integrate into demanding commercial and industrial setups. If you’re looking for a breaker that combines performance, reliability, and long-term value, the DK3400W checks all the boxes.

Key Features and Benefits

• Built for High-Demand Systems: 400 amp capacity supports heavy electrical loads with ease
• Fast, Reliable Protection: T186 trip unit helps prevent overloads and short circuits before they cause damage
• High Interrupting Capacity: Rated up to 65 kAIC at 240 Vac for handling fault conditions safely
• Flexible Voltage Compatibility: Works with both 240 Vac and 250 Vdc applications
• Three-Pole Design: Ideal for full-phase protection in commercial and industrial environments
• Proven Series C Platform: Widely trusted for consistent, long-term performance
• Efficient Footprint: K-frame design makes installation easier without sacrificing capability

Technical Specifications

• Catalog Number: DK3400W
  
• Product Type: Molded Case Circuit Breaker
  
• Series: Series C
  
• Frame Type: K Frame
  
• Amperage Rating: 400 A
  
• Voltage Rating: 240 Vac / 250 Vdc
  
• Interrupt Rating:
  • 65 kAIC at 240 Vac
  • 10 kAIC at 250 Vdc
• Number of Poles: 3
  
• Trip Type: T186
  
• Frequency Rating: 50–60 Hz
  
• Terminals: Without terminals
  
• Dimensions: 4.1 in (D) × 5.5 in (W) × 5.5 in (H)
  
• Weight: 11.4 lb
  

Material Compliance and Certifications

• UL Listed: meeting strict safety and performance standards for use in commercial and industrial electrical systems
• Manufactured: to meet industry expectations for durability, safety, and consistent operation

Where It Works Best

The Eaton DK3400W is a natural fit for industrial facilities, commercial buildings, and heavy-duty electrical distribution systems. It performs especially well in environments with large equipment, motor-driven systems, and continuous power demands, where reliability isn’t just important—it’s critical.