TJJ426300 **Older Style** - 300 Amp Circuit Breaker

TJJ426300 **Older Style** - 300 Amp Circuit Breaker

The TJJ426300 molded case circuit breaker is designed for dependable circuit protection in your commercial and industrial electrical distribution systems where consistent overcurrent protection is essential. Built as part of the trusted Q-Line family, this 2-pole, 300-amp breaker features a thermal-magnetic trip unit with internal common trip functionality to help you safeguard connected equipment from overloads and short circuits. Its older-style black-face configuration makes it a practical replacement for form, fit, and function, helping maintain existing installations and legacy electrical systems. The bolt-on mounting design provides secure installation, while the included load-side lugs simplify setup in compatible panelboard and switchgear applications. HACR rating further supports use in heating, air conditioning, and refrigeration systems where reliable protection is required. Built with durability in mind, the TJJ426300 is intended for long-term service in demanding environments where dependable power distribution matters every day.

Key Features and Benefits

• 300-amp molded case circuit breaker: Designed for commercial and industrial power distribution systems.
• Type TJJ configuration: For compatibility with designated legacy electrical equipment.
• Older style black face design: Supports form, fit, and functional replacement needs.
• Thermal magnetic trip unit: Delivers protection against overloads and short circuits.
• Internal common trip mechanism: Helps disconnect all poles simultaneously during fault conditions.
• Bolt-on mounting design: Provides a secure connection within compatible assemblies.
• HACR rated: For use in heating, air conditioning, and refrigeration applications.
• Includes load-side lugs: Added installation convenience.
• Built for demanding environments: Intended to withstand continuous operation in electrical distribution systems.
  

Technical Specifications

• Part Number: TJJ426300
  
• Product Type: Molded Case Circuit Breaker
  
• Circuit Breaker Type: TJJ
  
• Poles: 2
  
• Amperage Rating: 300 Amps
  
• Voltage / A.I.C. Rating:
  • 22k @ 600VAC
  • 30k @ 480VAC
  • 42k @ 240VAC
• Mounting Style: Bolt-On
  
• Trip Unit: Non-Interchangeable Thermal Magnetic
  
• Trip Function: Internal Common Trip
  
• Series: Q-Line
  
• 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: Approved for heating, air conditioning, and refrigeration applications.
• Manufactured Standards: Manufactured for use in accordance with applicable molded case circuit breaker standards.
• System Compatibility: Designed for compatibility within properly rated electrical distribution systems.
• Thermal Magnetic Protection: Supports established overcurrent protection requirements.
  

Where It Works Best

• The TJJ426300 circuit breaker is commonly used in commercial buildings, manufacturing facilities, industrial control systems, and large electrical distribution systems that require a 300-amp, 2-pole breaker. It is particularly well-suited for maintaining and servicing existing Q-Line installations where matching configuration, mounting style, and electrical ratings are important for continued operation. Typical applications include panelboards, switchgear assemblies, HVAC equipment, motor distribution systems, and facility power management infrastructure.