EF3B125 - 125Amp Circuit Breaker

EF3B125 - 125Amp Circuit Breaker

If you're replacing an existing EF3 frame molded case circuit breaker, the EF3B125 is designed to provide the electrical ratings and physical compatibility needed to keep your power distribution system operating as intended. Rated at 125 amps with a 3-pole configuration, this breaker helps protect three-phase electrical circuits from overloads and short circuits in commercial and industrial applications operating at up to 600VAC.

Whether you're performing scheduled maintenance, replacing a failed breaker, or servicing existing electrical equipment, selecting the correct amperage, pole configuration, and interrupting rating is essential. The EF3B125 features an interrupting capacity of 14kA at both 600VAC and 480VAC, along with 18kA at 240VAC, making it suitable for many legacy electrical distribution systems where these ratings are required.

Key Features and Benefits

• 125 Amp current rating for dependable overcurrent protection
• 3-pole configuration for three-phase commercial and industrial electrical systems
• Form, fit, and functional replacement for compatible EF3-frame applications
• Molded case construction built to last
• Interrupting ratings:
  • 14kA @ 600VAC
  • 14kA @ 480VAC
  • 18kA @ 240VAC
• Designed for operation in 40°C ambient environments
• Compact dimensions help simplify installation in compatible equipment
• Suitable for protecting branch circuits, feeders, motors, and other three-phase electrical equipment

Technical Specifications

• Part Number: EF3B125
  
• Type: EF3 Molded Case Circuit Breaker
  
• Poles: 3
  
• Amperage: 125 Amps
  
• Maximum Voltage: 600VAC
  
• Interrupting Rating: 14kA @ 600VAC; 14kA @ 480VAC; 18kA @ 240VAC
  
• Ambient Temperature Rating: 40°C
  
• Dimensions:
  • Width: 4.50 in.
  • Height: 6.00 in.
  • Depth: 3.63 in.
• Approximate Shipping Weight: 5.25 lbs.
  

Material Compliance and Certifications

The EF3B125 molded case circuit breaker is manufactured for installation in compatible electrical distribution equipment and is designed to meet the published electrical ratings for its frame and configuration. Before installation, verify compatibility with your panel, switchboard, or switchgear, and ensure all work is completed in accordance with applicable electrical codes and manufacturer recommendations. Any required certifications or listings should be confirmed for the specific application.

Where It Works Best

• Commercial buildings
• Industrial manufacturing facilities
• Distribution panels
• Switchboards
• Control panels
• Three-phase motor protection applications
• OEM electrical equipment
• Maintenance and repair of existing electrical systems