THJK436300 - 300Amp Circuit Breaker

THJK436300 - 300 Amp Circuit Breaker

The THJK436300 is a 300 amp, 3-pole molded case circuit breaker designed for use in your electrical distribution systems requiring dependable overcurrent and short-circuit protection. Built as part of the Q-Line™ family, this Type THJK4 circuit breaker features a thermal magnetic trip unit, internal common trip, and non-interchangeable trip configuration for consistent circuit protection. Its bolt-on mounting design helps you to provide a secure installation in compatible equipment, while the included load-side lugs simplify conductor termination. Engineered for commercial and industrial power distribution applications, the THJK436300 offers interrupting ratings of 25kA at 600VAC, 35kA at 480VAC, and 65kA at 240VAC, making it suitable for systems where higher available fault current levels must be considered. This breaker is also HACR rated, making it appropriate for heating, air conditioning, and refrigeration-related applications when installed according to applicable codes and equipment requirements. Built to last, the THJK436300 provides a form, fit, and functional replacement option for maintaining compatible electrical systems and equipment.

Key Features and Benefits

• 300 amp current rating: For higher-capacity power distribution applications.
• 3-pole configuration: For protection of three-phase electrical systems.
• Type THJK4 molded case circuit breaker design: Built as part of the Q-Line™ series.
• Bolt-on mounting: For secure installation in approved equipment.
• Thermal magnetic trip unit: Provides both overload and short-circuit protection.
• Internal common trip mechanism: Helps ensure all poles trip simultaneously during fault conditions.
• Non-interchangeable trip unit configuration: Designed for consistent circuit protection.
• HACR rated: For compatible heating, air conditioning, and refrigeration applications.
• Includes load-side lugs: For convenient conductor connections.
• Designed for long service life: In commercial and industrial environments.
  

Technical Specifications

• Part Number: THJK436300
  
• Type: THJK4
  
• Series: Q-Line™
  
• Current Rating: 300 Amps
  
• Number of Poles: 3
  
• Trip Unit: Thermal Magnetic
  
• Trip Configuration: Non-Interchangeable
  
• Common Trip: Internal Common Trip
  
• Mounting Type: Bolt-On
  
• Interrupting Rating:
  • 25kA @ 600VAC
  • 35kA @ 480VAC
  • 65kA @ 240VAC
• HACR Rated: Yes
  
• Included Accessories: Load-Side Lugs
  
• Dimensions:
  • Height: 10.13 in.
  • Width: 8.25 in.
  • Depth: 3.81 in.

Material Compliance and Certifications

• HACR Rated: HACR Rated.
• Industry Standards: Manufactured and tested to applicable industry standards for molded case circuit breakers.
• Installation Requirements: Intended for installation and use in accordance with applicable electrical codes, manufacturer specifications, and system requirements.
• Equipment Compatibility: Suitable for use in properly rated and compatible electrical distribution equipment.
  

Where It Works Best

• The THJK436300 is commonly used in commercial buildings, industrial facilities, manufacturing operations, distribution equipment, switchboards, panelboards, and large HVAC systems where a 300 amp, 3-pole circuit breaker is required. Its combination of thermal magnetic protection, bolt-on installation, and high interrupting capacity makes it well suited for protecting feeders, distribution circuits, and other three-phase power applications in compatible electrical systems.