THJK426400WL - 400Amp Circuit Breaker

THJK426400WL - 400 Amp Circuit Breaker

The THJK426400WL is a 400-amp, 2-pole molded case circuit breaker designed for use in your commercial and industrial electrical distribution systems requiring dependable overcurrent and short-circuit protection. As part of the THJK4 Q-Line family, this breaker features a thermal magnetic trip unit with an internal common trip, providing protection against both overloads and fault conditions while helping maintain system safety and continuity.

Configured with a cable-in/cable-out (lug-lug) design, the THJK426400WL includes both line-side and load-side lugs, simplifying installation and conductor termination. Its non-interchangeable trip unit provides fixed protection settings, making it well-suited for applications where a dedicated trip rating is required. The breaker is also HACR rated, supporting use in heating, air conditioning, and refrigeration equipment applications where applicable.

Built to last and engineered for dependable operation, the THJK426400WL is commonly used in switchboards, panelboards, distribution equipment, and other high-current power distribution applications requiring a 400A breaker with substantial interrupting capacity.

Key Features and Benefits

• 400 Amp Current Rating: 400 Amp current rating for high-capacity electrical distribution applications.
• 2-Pole Configuration: 2-pole configuration for protection of 240V, 480V, and 600V AC systems as applicable.
• THJK4 Q-Line Design: THJK4 Q-Line molded case circuit breaker design.
• Thermal Magnetic Protection: The thermal magnetic trip unit provides overload and short-circuit protection.
• Internal Common Trip: The internal common trip mechanism helps ensure both poles trip simultaneously during fault conditions.
• Cable-In/Cable-Out Configuration: Cable-in/cable-out (lug-lug) configuration for straightforward field wiring.
• Included Lugs: Includes both line-side and load-side lugs.
• HACR Rated: HACR rated for qualifying heating, air conditioning, and refrigeration applications.
• Fixed Protection Settings: Non-interchangeable trip unit with fixed protection characteristics.
• Versatile Applications: Suitable for commercial, industrial, and institutional power distribution systems.

Technical Specifications

• Part Number: THJK426400WL
  
• Type: THJK4
  
• Product Family: Q-Line
  
• Circuit Breaker Type: Molded Case Circuit Breaker
  
• Poles: 2
  
• Amperage Rating: 400A
  
• Trip Unit: Thermal Magnetic
  
• Trip Style: Internal Common Trip
  
• Configuration: Cable-In/Cable-Out (Lug-Lug)
  
• Included Accessories: Line-Side and Load-Side Lugs
  
• Interrupting Rating: 25kA @ 600VAC
  
• Interrupting Rating: 35kA @ 480VAC
  
• Interrupting Rating: 65kA @ 240VAC
  
• Dimensions:
  • Height: 10.13 in.
  • Width: 8.25 in.
  • Depth: 3.81 in.
• HACR Rated: Yes
  

Material Compliance and Certifications

• HACR Rated: HACR Rated for applicable heating, air conditioning, and refrigeration equipment installations.
• Electrical Distribution Applications: Manufactured for use in electrical distribution systems requiring molded case circuit breaker protection.
• Industry Standards: Designed to meet applicable industry standards associated with its ratings and intended use.
• Installation Requirements: Verify local code requirements and application-specific compliance requirements prior to installation.

Where It Works Best

• The THJK426400WL is well-suited for commercial and industrial environments where high-current circuit protection is required. Typical applications include power distribution panels, switchboards, industrial control systems, manufacturing facilities, commercial buildings, mechanical equipment power feeds, HVAC and refrigeration systems requiring HACR-rated protection, and electrical infrastructure requiring a 400A, 2-pole molded case circuit breaker.
• When proper form, fit, and ratings are required, the THJK426400WL provides a practical solution for maintaining existing electrical distribution systems while delivering the overcurrent protection expected from a molded case circuit breaker in demanding applications.