JD63B400 - 400Amp Circuit Breaker

JD63B400 - 400Amp Circuit Breaker

The Siemens JD63B400 is a 400A, three-pole SENTRON molded-case circuit breaker with a JD frame and a thermal-magnetic trip unit. When you're sourcing this breaker for existing or legacy equipment, the connection details are worth checking alongside the electrical ratings. For replacement work, confirm the full specification set—including frame, amperage, poles, voltage, AIC rating, dimensions, lug arrangement, and conductor range—to make sure the breaker is right for the equipment already in place.

Key Features and Benefits

• 400A, three-pole configuration: Provides the exact amperage and pole count needed when matching equipment that calls for the JD63B400.
• JD frame: An important form-and-fit detail to verify when sourcing a replacement for existing electrical equipment.
• Thermal-magnetic trip unit: Matches the trip-unit type identified in the Siemens specifications.
• Load-side lugs included: Both sides use TA2J6500 lugs, removing any ambiguity about the manufacturer-specified lug arrangement.
• Copper or aluminum conductors: Accepts 3/0 AWG–500 kcmil copper and 4/0 AWG–500 kcmil aluminum conductors.
• Standard 40°C rating: Clearly identified in the manufacturer data for easier specification matching.
  

Technical Specifications

• Manufacturer: Siemens
  
• Catalog Number / MFN: JD63B400
  
• Article Number: US2:JD63B400
  
• Product Line: SENTRON
  
• Product Type: Molded Case Circuit Breaker
  
• Frame: JD
  
• Amperage Rating: 400A
  
• Number of Poles: 3
  
• Voltage Rating: 600V
  
• Trip Unit: Thermal-magnetic
  
• Temperature Rating: Standard 40°C
  
• Interrupting Capacity at 600V: 25 kAIC
  
• Interrupting Capacity at 480V: 35 kAIC
• Load-Side Lugs: TA2J6500
  
• Copper Conductor Range: 3/0 AWG–500 kcmil
  
• Aluminum Conductor Range: 4/0 AWG–500 kcmil
  
• Width: 7.5 in.
  
• Height: 11 in.
  
• Depth: 4 in.
  
• UPC: 783643213210
  
• Commodity Code: 8536200020
  
• Country of Origin: Mexico
  
• Standards: UL 489 / IEC 60947-2
  

Material Compliance and Certifications

Siemens states that the JD63B400 meets UL 489 and IEC 60947-2 standards. This wording is important: the supplied manufacturer information says the product meets these standards but does not separately identify this catalog number as UL Listed, so that additional certification claim should not be assumed.

Where It Works Best

The Siemens JD63B400 is suited to compatible existing and legacy electrical equipment that specifically requires a 400A, three-pole JD-frame molded case circuit breaker with the corresponding thermal-magnetic trip configuration. Because TA2J6500 lugs are supplied on the load sides, the lug type and the specified copper or aluminum conductor ranges should be included in the compatibility check.