HN3B400 - 400Amp Circuit Breaker

HN3B400 - 400Amp Circuit Breaker

The Siemens HN3B400 is a 400-amp, three-pole molded-case circuit breaker designed for electrical distribution systems that require an HN3 frame configuration. This breaker is rated for use in 40°C environments and offers interrupt ratings of 42 kA at 600 VAC, 65 kA at 480 VAC, and 65 kA at 240 VAC.

When you're replacing a circuit breaker in existing equipment, the small details make a big difference. The amperage rating is only one part of the match—the frame type, number of poles, voltage rating, and interrupt capacity all need to line up with the system requirements.

Key Features and Benefits

• 400A rating: Designed for applications requiring a 400-amp molded case circuit breaker.
• Three-pole design: Fits systems that require three-pole circuit protection.
• HN3 frame configuration: Provides the frame style required for compatible equipment.
• 40°C rating: Suitable for applications operating within the specified temperature range.
• Molded case construction: Common breaker format used in many electrical distribution systems.
  

Technical Specifications

• Part Number: HN3B400
  
• Manufacturer: Siemens
  
• Product Type: Molded case circuit breaker
  
• Frame Type: HN3
  
• Amperage Rating: 400 A
  
• Number of Poles: Three-pole
  
• A.I.C. Rating:42 kA at 600 VAC
  
• 65 kA at 480 VAC
  
• 65 kA at 240 VAC
  
• Temperature Rating: 40°C
  
• Construction: Molded case circuit breaker
  
• Approximate Ship Weight: 42.00 lbs
  
• Dimensions: 9.00"W x 15.50"L x 4.00"D
  
• Height: 15.5 in.
  
• Width: 9.0 in.
  
• Depth: 4.0 in.
  

Material Compliance and Certifications

The available product information identifies the Siemens HN3B400 as a molded-case circuit breaker, but it does not list any additional material compliance details or certifications.

For projects with specific regulatory, environmental, or material requirements, those requirements should be confirmed separately before installation.

Where It Works Best

The Siemens HN3B400 is best suited for electrical distribution equipment that calls for a 400A, three-pole breaker with an HN3 frame configuration. It is especially useful in maintenance and replacement situations where matching the existing breaker specifications is the priority.

Before selecting a replacement, check the complete electrical requirements—not just the amp rating. Verify the frame type, pole count, voltage rating, and interrupting capacity to ensure the breaker matches the equipment it will be installed in.