LB3400 - 400Amp Circuit Breaker

LB3400 - 400Amp Circuit Breaker

The LB3400 is a 400-amp, 3-pole Type LB thermal-magnetic circuit breaker with an interchangeable trip unit. It is rated 22kA at 600VAC, 30kA at 480VAC, and 42kA at 240VAC, giving you three clear reference points when checking it against an existing application. For maintenance and replacement jobs, the LB3400 makes the most sense when the existing equipment requires this combination of Type LB construction, amperage, poles, interrupting capacity, trip-unit style, and physical size. When properly matched to the equipment, installed correctly, and kept within its specified ratings, the LB3400 is built to last in its intended application.

Key Features and Benefits

• 400A rating for equipment designed around this specific current rating
• 3-pole Type LB configuration
• Thermal-magnetic circuit breaker
• Interchangeable trip unit
• Rated for 40°C
• Load-side terminals included
• Published dimensions make it easier to check physical compatibility before installation
• Suitable for form, fit, and functional replacement where the complete specifications match the existing equipment
  

Technical Specifications

• Part Number: LB3400
  
• Type: LB
  
• Amperage: 400A
  
• Poles: 3
  
• Breaker Type: Thermal-magnetic
  
• Trip Unit: Interchangeable
  
• AIC Rating: 22kA @ 600VAC
  
• AIC Rating: 30kA @ 480VAC
  
• AIC Rating: 42kA @ 240VAC
  
• Temperature Rating: 40°C
  
• Terminals: Load-side terminals included
  
• Height: 10.13 in.
  
• Width: 5.50 in.
  
• Depth: 3.94 in.
  
• Overall Dimensions: 5.50"W x 10.13"L x 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 details were supplied for the LB3400. Do not assume those credentials from the Type LB designation or electrical ratings.

Where It Works Best

The LB3400 belongs in applications that call for a 400A, 3-pole Type LB thermal-magnetic circuit breaker with an interchangeable trip unit. That can make it a useful replacement candidate for compatible existing and legacy electrical equipment where maintaining the original form, fit, and function is the priority.

Before making the match, compare the system voltage and required interrupting capacity with the LB3400's ratings: 22kA at 600VAC, 30kA at 480VAC, and 42kA at 240VAC.