3VA5212-7EC31-0AA0 - CFAS 125 Amp Circuit Breaker

3VA5212-7EC31-0AA0 - CFAS 125 Amp Circuit Breaker

When you’re choosing a 125 amp circuit breaker, you’re not looking for something fancy—you’re looking for something that works every time. The Siemens 3VA5212-7EC31-0AA0 is exactly that. It’s built for real-world electrical systems where reliability matters more than anything else. This 3-pole Siemens breaker is part of the 3VA5 series, designed to handle everyday commercial and industrial loads without overcomplicating the install. It uses a thermal magnetic trip unit, so it reacts the way you expect—steady protection for overloads and fast action when a short circuit hits. What makes this model stand out is its 100kA interrupting rating at 480V. That’s not just a number—it means this breaker is ready for environments where fault current is higher and mistakes are expensive. It gives you a level of confidence that’s hard to get with lower-rated units. And because the trip settings are fixed, there’s no fine-tuning or second-guessing. You install it, and it does exactly what it’s designed to do—protect your system and stay out of your way.

Key Features and Benefits

• 125 amp circuit breaker for commercial and industrial applications
• 3-pole design for three-phase power distribution
• 100kA @ 480V interrupting rating for high fault current protection
• Thermal magnetic trip unit (TM230)—simple, proven, and dependable
• Fixed overload protection (Ir = 125A) for consistent performance
• Instantaneous trip at 10x In for quick short-circuit response
• Compact design that fits well in panels and equipment setups

Technical Specifications

• Part Number: 3VA5212-7EC31-0AA0
  
• Series: Siemens 3VA52
  
• Poles: 3
  
• Amperage: 125A
  
• Voltage Rating: Up to 480V
  
• Interrupting Capacity: 100kA @ 480V
  
• Trip Type: Thermal Magnetic (TM230)
  
• Overload Protection (Ir): 125A (fixed)
  
• Short-Circuit Protection (Ii): 10 × In
  
• Dimensions:
  • Height: 9.65 in
  • Width: 6.3 in
  • Depth: 5.9 in

Material Compliance and Certifications

• Meets UL standards for molded case circuit breakers
• Built for compliance with North American electrical codes
• Manufactured to Siemens quality standards for consistent, long-term use

Where It Works Best

• You’ll typically see this Siemens 125A breaker in commercial buildings, industrial panels, and equipment protection setups. It’s a strong fit for distribution systems, motor protection, and retrofit projects where you need solid performance without overthinking the setup. If you’re working in a system with higher available fault current—or you just want a breaker you don’t have to worry about later—this one earns its place pretty quickly.