TJJ426400WL **Older Style** - 400Amp Circuit Breaker

TJJ426400WL **Older Style** - 400 Amp Circuit Breaker

The TJJ426400WL Older Style Black Face molded case circuit breaker is built for your electrical systems that still depend on dependable, properly matched protection components to keep operations running smoothly. Designed as part of the well-known Q-Line series, this 2-pole, 400-amp breaker delivers the kind of steady overcurrent protection commonly required in commercial and industrial environments where downtime is never convenient. Its thermal magnetic trip unit reacts to both overloads and short circuits, helping you protect connected equipment while supporting safe system operation day after day.

What makes this breaker especially useful for many facilities is its compatibility with existing legacy equipment layouts. The older style black face design helps maintain the original look and fit of compatible installations, making it a practical form, fit, and functional replacement when servicing or maintaining existing electrical infrastructure. The cable-in/cable-out lug-lug configuration also keeps installation straightforward, and both line-side and load-side lugs are included to help simplify setup in the field. Built to last and designed for demanding electrical applications, this breaker continues to be a dependable choice for panelboards, switchboards, HVAC systems, and power distribution equipment requiring a 400A molded case circuit breaker with strong interrupting ratings.

Key Features and Benefits

• Q-Line Molded Case Circuit Breaker: Designed for commercial and industrial power distribution applications requiring dependable overcurrent protection.
• 2-Pole, 400-Amp Configuration: Supports high-capacity electrical applications where reliable circuit protection is essential.
• Thermal Magnetic Trip Unit: Helps respond to overloads and short circuits to protect connected equipment and support safe electrical system operation.
• Internal Common Trip Mechanism: Supports coordinated circuit interruption during fault conditions.
• Cable-In/Cable-Out Lug-Lug Design: Allows for secure conductor termination and simplified installation.
• Includes Line-Side and Load-Side Lugs: Helps simplify setup and field installation requirements.
• HACR Rated: Suitable for heating, air conditioning, and refrigeration equipment applications.
• Older Style Black Face: Supports compatibility with existing legacy electrical systems and helps preserve original equipment fitment.
• Built for Long-Term Use: Designed for demanding operating environments requiring dependable molded case circuit breaker performance.
  

Technical Specifications

• Part Number: TJJ426400WL
  
• Series: Q-Line
  
• Type: TJJ
  
• Circuit Breaker Type: Molded Case Circuit Breaker
  
• Trip Unit: Non-Interchangeable Thermal Magnetic Trip Unit
  
• Poles: 2
  
• Amperage Rating: 400A
  
• Interrupting Capacity:
  • 22k @ 600VAC
  • 30k @ 480VAC
  • 42k @ 240VAC
• Configuration: Cable-in/Cable-out (Lug-Lug)
  
• Dimensions:
  • Height: 10.13 in.
  • Width: 8.25 in.
  • Depth: 3.81 in.
• Face Style: Older Style Black Face
  

Material Compliance and Certifications

• HACR Rated: Suitable for heating, air conditioning, and refrigeration equipment applications.
• Industry Compatibility: Designed for use in commercial and industrial electrical distribution systems.
• Operating Standards: Manufactured for compatibility with applicable molded case circuit breaker applications and industry operating standards.
  

Where It Works Best

• The TJJ426400WL is commonly installed in commercial facilities, manufacturing plants, HVAC systems, distribution equipment, and industrial electrical panels where dependable 400A circuit protection is required. It works particularly well in existing systems using compatible Q-Line breaker configurations, helping maintenance teams preserve equipment fitment without major modifications to the original setup. Its high interrupting capacity and durable construction also make it a solid choice for demanding power distribution environments where consistent protection matters.