3VA5340-7EF31-0AA0 - 400A Class CJAS 3-Pole Circuit Breaker

3VA5340-7EF31-0AA0 - 400A Class CJAS 3-Pole Circuit Breaker

This Siemens 3VA5340-7EF31-0AA0 is a 400 amp, 3-pole circuit breaker made for standard commercial and industrial use. Nothing fancy—just a solid unit designed to handle overloads and short circuits the way it should. It comes with a thermal magnetic trip unit (TM240), which is what most people expect in this range. The overload setting can be adjusted from 320A up to 400A, so you’ve got some room to match it to your system. The instantaneous trip is also adjustable, set between 5 and 10 times the rated current. It’s rated at 100 kA at 480V AC, so it’s suitable for systems where higher fault current is a concern. Size-wise, it’s pretty typical for a 400A frame, so it should fit into most standard setups without much trouble. Lugs aren’t included, so you’ll need to account for that. If you just need a dependable 400A breaker without getting into anything overly complicated, this one gets the job done.

Key Features and Benefits

• 400 amp rating
• 3-pole breaker for three-phase systems
• Thermal magnetic trip unit (TM240)
• Adjustable overload: 320A to 400A
• Instantaneous trip: 5–10x
• 100 kA rating at 480V AC
• Standard size for this frame

Technical Specifications

• Part Number: 3VA5340-7EF31-0AA0
  
• Series: 3VA5
  
• Amperage: 400A
  
• Poles: 3
  
• Trip Unit: Thermal Magnetic (TM240, ATAM)
  
• Overload Range (Ir): 320–400A
  
• Short-Circuit Range (Ii): 5–10x
  
• Interrupting Rating: 100 kA @ 480V AC
  
• Dimensions: 9.8" H × 6.3" W × 5.9" D
  
• Lugs: Not included
  

Material Compliance and Certifications

• UL listed
• Meets standard electrical safety requirements
• Suitable for commercial and industrial applications

Where It Works Best

Commonly used in panelboards and switchboards in commercial buildings or industrial facilities. Fits anywhere a 400A, 3-pole breaker is needed and adjustable protection is useful.