TJJ436300 - 300A Circuit Breaker

TJJ436300 - 300A Circuit Breaker

When your electrical systems are expected to carry heavy loads day after day, having the right circuit breaker in place matters. The TJJ436300 molded case circuit breaker is built for dependable protection in commercial and industrial power distribution systems where reliability and compatibility are key. Designed as part of the well-known Q-Line series, this 3-pole, 300-amp breaker helps protect equipment and electrical circuits from overloads and short circuits while fitting seamlessly into existing compatible systems.

Its thermal magnetic trip unit reacts to both prolonged overload conditions and sudden fault currents, helping reduce the risk of damage to connected equipment. The internal common trip design ensures all poles disconnect together when needed, an important feature for maintaining safer operation in three-phase systems. Because it’s a bolt-on breaker, installation remains secure and stable in properly matched panelboards and switchboards.

The TJJ436300 is also HACR rated, making it a suitable choice for heating, air conditioning, and refrigeration applications often found in commercial buildings, industrial facilities, and mechanical equipment rooms. Load-side lugs are included to help simplify installation and reduce setup time on the jobsite. Built with durability in mind, this molded case circuit breaker is designed to hold up in demanding electrical environments where dependable protection is essential.

Key Features and Benefits

• 300 Amp Continuous Current Rating: Designed for demanding commercial and industrial applications requiring dependable high-capacity electrical protection.
• 3-Pole Design: Intended for use in three-phase electrical systems commonly found in industrial and commercial environments.
• Thermal Magnetic Trip Unit: Helps provide overload and short-circuit protection by responding to both prolonged overload conditions and sudden fault currents.
• Internal Common Trip Mechanism: Disconnects all poles simultaneously during fault conditions to support safer operation in three-phase systems.
• Bolt-On Mounting Design: Supports a secure installation in compatible panelboards and switchboards.
• Q-Line Family Compatibility: Designed as part of the Q-Line series for compatibility with existing legacy systems.
• HACR Rated: Suitable for heating, air conditioning, and refrigeration equipment applications.
• Includes Load-Side Lugs: Helps simplify installation and reduce setup time on the jobsite.
• Molded Case Construction: Built for long-term use in demanding operating environments where dependable protection is essential.
  

Technical Specifications

• Part Number: TJJ436300
  
• Type: TJJ
  
• Product Family: Q-Line
  
• Circuit Breaker Type: Molded Case Circuit Breaker
  
• Trip Unit: Thermal Magnetic
  
• Trip Style: Non-Interchangeable
  
• Poles: 3
  
• Amperage Rating: 300 Amps
  
• Voltage & A.I.C. Ratings: 22k @ 600VAC; 30k @ 480VAC; 42k @ 240VAC
  
• Mounting Style: Bolt-On
  
• Dimensions:
  • Height: 10.13 in
  • Width: 8.25 in
  • Depth: 3.81 in
• Included Accessories: Load-Side Lugs
  
• Application Rating: HACR Rated
  

Material Compliance and Certifications

• Industry Standards: The TJJ436300 molded case circuit breaker is manufactured for use in electrical distribution systems requiring dependable overcurrent protection and compatibility with applicable industry installation standards.
• HACR Rating: Its HACR rating supports use in heating, air conditioning, and refrigeration systems where approved by system requirements and local electrical codes.
  

Where It Works Best

• The TJJ436300 works especially well in commercial facilities, industrial plants, manufacturing operations, office buildings, and large HVAC installations that require a 300A, 3-pole molded case circuit breaker. It is commonly used as a form, fit, and functional replacement in existing Q-Line electrical systems where maintaining compatibility with installed equipment is important. Whether installed in panelboards, switchboards, or distribution equipment, this breaker is designed to provide consistent circuit protection in everyday operating conditions.