LD63B300 - 300Amp Circuit Breaker

LD63B300 - 300Amp Circuit Breaker

The LD63B300 is a 300-amp, 3-pole LD frame molded case circuit breaker with a thermal-magnetic trip unit. It's rated for 600V, with an interrupting capacity of 25kA at 600V and 35kA at 480V. If you're sourcing one for equipment already in service, confirm the match before installation. For existing or legacy equipment, compare the frame, amperage, voltage, AIC, connections, and physical size with the breaker you're replacing. When the LD63B300 is properly matched to compatible equipment, installed correctly, and operated within its specified ratings, it's built to last in the application it was designed for.

Key Features and Benefits

• 300A, 3-pole configuration for equipment requiring this specific LD frame arrangement
• Thermal-magnetic trip unit
• 600V rating
• 40°C rated
• Load lugs included, using TA2J6500 lugs
  

Technical Specifications

• Catalog Number: LD63B300
  
• Article Number: US2\:LD63B300
  
• Product Type: Molded Case Circuit Breaker
  
• Frame: LD
  
• Trip Type: Thermal-Magnetic
  
• Amperage: 300A
  
• Number of Poles: 3
  
• Voltage Rating: 600V
  
• AIC at 600V: 25kA
  
• AIC at 480V: 35kA
  
• Temperature Rating: 40°C
  
• Load-Side Lugs: TA2J6500
  
• Copper Wire Range: 3/0 AWG–500 kcmil
  
• Aluminum Wire Range: 4/0 AWG–500 kcmil
  
• Dimensions: 7.5"W x 11"H x 4"D
  
• Net Weight: 20.701 lb
  
• Country of Origin: Mexico
  

Material Compliance and Certifications

The LD63B300 meets UL 489 and IEC 60947-2 standards, providing documented standards information you can check against equipment and installation requirements.

Where It Works Best

The LD63B300 makes sense for maintenance and replacement work where the existing equipment calls for a 300A, 3-pole LD frame thermal-magnetic circuit breaker. This is especially relevant for legacy systems where the objective is to maintain the required form, fit, and function.