BJ3125 - 125 Amp Circuit Breaker

BJ3125 - 125 Amp Circuit Breaker

The Eaton BJ3125 is a 125A, 3-pole thermal magnetic circuit breaker used as a main breaker in compatible Eaton BJ-series loadcenters. Rated for 240V AC systems, it provides overload and short-circuit protection for your commercial, industrial, multifamily, and larger residential electrical distribution systems.

Its plug-on mounting configuration is designed for use in Eaton loadcenters rated 150 amps and above, and it accepts copper or aluminum conductors ranging from #2 AWG to 300 kcmil.

With a 10 kAIC interrupting rating and UL 489 listing, the BJ3125 meets established industry requirements for circuit protection. It is often used for your panel replacements, maintenance projects, service equipment repairs, and applications where matching the original breaker type and loadcenter configuration is important. Like many Eaton breakers installed throughout North America, it was built for long service life when properly installed and maintained.

Key Features and Benefits

• 125A current rating
• Three-pole configuration
• Thermal magnetic trip unit
• Common-trip operation
• Plug-on mounting design
• Rated for 240V AC systems
• 10 kAIC interrupting rating
• Accepts copper or aluminum conductors
• Wire range: #2 AWG to 300 kcmil

Technical Specifications

• Manufacturer: Eaton
  
• Catalog Number: BJ3125
  
• Product Type: Thermal Magnetic Circuit Breaker
  
• Series: BJ
  
• Type: BJ 1-Inch Plug-On Main Breaker
  
• Amperage Rating: 125A
  
• Voltage Rating: 240V AC
  
• Number of Poles: 3
  
• Trip Type: Common Trip
  
• Mounting Method: Plug-On
  
• Interrupt Rating: 10 kAIC
  
• Wire Size Range: #2 AWG to 300 kcmil Cu/Al
  
• Minimum Loadcenter Requirement: 150A
  
• Space Requirement: Three 1-inch pole spaces on the left side and three 1-inch pole spaces on the right side of compatible loadcenters
  
• Dimensions:
  • Length: 8 in.
  • Width: 3.5 in.
  • Height: 3.5 in.
• Weight: 2.5 lbs
  

Material Compliance and Certifications

• UL 489 Listed
• Federal Specifications Classification W-C375 Compliant

Where It Works Best

• The Eaton BJ3125 is used in compatible Eaton BJ-series loadcenters serving commercial buildings, industrial facilities, multifamily properties, and larger residential electrical systems.