KM3B300 - 300Amp Circuit Breaker

KM3B300 - 300Amp Circuit Breaker

With the KM3B300, the 300-amp rating is only part of what identifies the breaker. Put the KM3B300 specifications alongside the breaker being removed and the equipment requirements, paying attention to the frame, breaker type, pole count, dimensions, amperage, and the AIC rating for your system voltage. When the complete electrical and physical configuration lines up, the KM3B300 may provide the required form, fit, and function for the installation.

Key Features and Benefits

• 300-amp rating for equipment designed around this current rating.
• 3-pole configuration provides a clearly defined characteristic for matching the breaker to the application.
• Type KM4 molded case circuit breaker construction.
• Specified with a Type ET 800 Ampere "KM" Frame, an important detail when identifying the correct breaker configuration.
• 40°C temperature specification gives maintenance personnel another characteristic to compare with existing equipment requirements.
• Well-suited to legacy equipment maintenance when the KM3B300's complete specifications align with the existing system.
  

Technical Specifications

• Part Number: KM3B300
  
• Product Type: Molded Case Circuit Breaker
  
• Type: KM4
  
• Frame: Type ET 800 Ampere “KM” Frame
  
• Amperage: 300A
  
• Poles: 3
  
• AIC at 600VAC: 22k
  
• AIC at 480VAC: 30k
  
• AIC at 240VAC: 42k
  
• Temperature Specification: 40°C
  
• Width: 9.00 in.
  
• Length/Height: 15.50 in.
  
• Depth: 4.00 in.
  
• Overall Dimensions: 9.00"W x 15.50"L x 4.00"D
  
• Approximate Shipping Weight: 40.00 lbs.
  

Material Compliance and Certifications

No specific certification or material compliance information was provided for the KM3B300, so listings or standards such as UL, RoHS, REACH, or similar designations should not be assumed.

Where It Works Best

The KM3B300 is best suited for existing and legacy electrical systems that require a 300A, 3-pole Type KM4 molded-case circuit breaker with the specified Type ET 800 Ampere "KM" Frame. In these applications, preserving the correct form, fit, and function starts with matching the breaker as a complete component rather than choosing by amperage alone.