LB3400F - 400Amp Max. *Frame Only*

LB3400F - 400Amp Max. *Frame Only*

The LB3400F is a 400-amp, 3-pole Type LB thermal-magnetic circuit breaker frame rated for 40°C operation. Its interrupting ratings are 22kA at 600VAC, 30kA at 480VAC, and 42kA at 240VAC. Just as important, this is a FRAME ONLY product—not a complete circuit breaker assembly. That distinction matters when you're replacing a component in equipment that's already in service. Properly selected, completed with the components required by the application, installed, and operated within its specified ratings, the LB3400F is built to last in the job it was designed to do.

Key Features and Benefits

• 400A, 3-pole Type LB frame
• FRAME ONLY configuration
• Thermal-magnetic circuit breaker frame
• Rated for 40°C
• Published dimensions make it easier to check physical compatibility
• Suitable for form, fit, and functional replacement when the complete specifications match the existing application
• A practical choice for compatible existing and legacy equipment requiring this specific Type LB frame
  

Technical Specifications

• Part Number: LB3400F
  
• Type: LB
  
• Configuration: Frame only
  
• Amperage: 400A
  
• Poles: 3
  
• Type of Breaker: Thermal-magnetic
  
• AIC at 600VAC: 22kA
  
• AIC at 480VAC: 30kA
  
• AIC at 240VAC: 42kA
  
• Temperature Rating: 40°C
  
• Height: 10.13 in.
  
• Width: 5.50 in.
  
• Depth: 3.94 in.
  
• Dimensions: 5.50"W × 10.13"L × 3.94"D
  
• Approx. Ship Weight: 16.00 lbs.
  

Material Compliance and Certifications

No specific UL, CSA, IEC, RoHS, REACH, or other certification or material-compliance information was provided for the LB3400F. Don't assume those details based on the Type LB designation or electrical ratings.

Where It Works Best

The LB3400F makes the most sense in existing equipment that specifically requires a 400A, 3-pole Type LB frame with these dimensions and interrupting ratings. It can be especially relevant when maintaining legacy electrical equipment, and the objective is to preserve the original form, fit, and function.

Since you're working with a frame only, make sure you account for the rest of the required assembly. Confirm the trip-unit requirements and any other components the equipment calls for. They shouldn't be assumed to come with the frame.