DK3400 - 400Amp Circuit Breaker

DK3400 - 400 Amp Circuit Breaker

If you’re dealing with high electrical loads, you don’t want to second-guess your protection. The Eaton DK3400 is built for exactly that kind of environment—where reliability matters and failure isn’t an option. This 400 amp, three-pole molded case circuit breaker is part of Eaton’s trusted Series C line, giving you consistent, proven performance in demanding commercial and industrial systems.

What makes this breaker stand out is its ability to handle serious fault conditions without hesitation. With an interrupting rating of 65 kAIC at 240 VAC and 10 kAIC at 250 VDC, it’s designed to step in fast and protect your equipment when it counts. The T186 trip unit delivers accurate, dependable response, while the aluminum line and load terminals make installation straightforward and secure.

Whether you're maintaining an existing setup or building out a new system, the DK3400 gives you the confidence that your electrical infrastructure is protected by a component that’s built to perform day in and day out.

Key Features and Benefits

• Built for High-Demand Systems – 400 amp capacity handles heavy electrical loads with ease
• Fast, Reliable Protection – Strong interrupting ratings help prevent damage during fault conditions
• Three-Pole Design – Ideal for balanced, three-phase power distribution
• Consistent Trip Performance – T186 trip unit ensures precise circuit interruption
• Proven Series C Platform – Widely trusted for performance and longevity
• AC and DC Compatibility – Works across multiple system requirements
• Easy, Secure Connections – Aluminum terminals designed for solid contact and efficient installs

Technical Specifications

• Catalog Number: DK3400
  
• Product Type: Molded Case Circuit Breaker
  
• Series: Series C
  
• Frame Type: K Frame
  
• Breaker Type: DK
  
• Amperage Rating: 400 A
  
• Voltage Rating: 240 VAC / 250 VDC
  
• Frequency Rating: 50–60 Hz
  
• Number of Poles: 3
  
• Trip Type: T186
  
• Interrupt Rating:
  • 65 kAIC at 240 VAC
  • 10 kAIC at 250 VDC
• Terminal Material: Aluminum
  
• Terminals: Line and Load
  
• Dimensions: 14 in (L) x 7 in (W) x 6.5 in (H)
  
• Weight: 12.6 lb
  

Material Compliance and Certifications

• UL Listed – Meets recognized U.S. safety standards for electrical protection and performance

Where It Works Best

• Commercial facilities and large office buildings
• Industrial plants and manufacturing operations
• Electrical distribution panels and switchgear
• Infrastructure and utility-related installations
• Replacement projects requiring a compatible Series C breaker