QPJ3125 - 125Amp Circuit Breaker

QPJ3125 - 125Amp Circuit Breaker

Replacing a main breaker isn't just about matching the amperage. The breaker also needs to fit the equipment, connect properly, and have the electrical ratings the system was designed around. The Siemens QPJ3125 125 Amp 3-Pole Circuit Breaker is a Type QPJ plug-in breaker rated for 240V AC and 10kA interrupting capacity. Designed for compatible electrical distribution equipment, it uses a thermal-magnetic trip mechanism to help protect circuits against overloads and short circuits. If you're maintaining an existing load center that calls for a QPJ3125, matching these details is key to getting the replacement right.

Key Features and Benefits

• 125-Amp Current Rating: Designed for electrical distribution applications that require a 125-amp circuit breaker.
• Three-Pole Configuration: Provides three-pole circuit protection in equipment designed for this arrangement.
• Thermal-Magnetic Protection: Responds to overload conditions and short circuits through its thermal-magnetic trip mechanism.
• 10kA Interrupting Capacity: Rated to interrupt fault currents up to 10,000 amps at 240V AC.
• Type QPJ Plug-In Design: Intended for compatible load centers and electrical distribution equipment approved for QPJ breakers.

Technical Specifications

• Manufacturer: Siemens
  
• Catalog Number: QPJ3125
  
• Manufacturer Article Number: US2
  
• Product Category: Low-Voltage Circuit Breaker
  
• Breaker Type: QPJ
  
• Breaker Configuration: Plug-In
  
• Application: Electrical Distribution
  
• Amperage Rating: 125 Amps
  
• Number of Poles: 3
  
• Voltage Rating: 240V AC
  
• Interrupting Rating (A.I.C.): 10kA at 240V AC
  
• Trip Mechanism: Thermal-Magnetic
  
• Applicable Standard: UL 489
  
• UPC: 783643264953
  
• Country of Origin: Dominican Republic
  
• Net Weight: Approximately 3.263 lbs.
  

Material Compliance and Certifications

Electrical ratings matter, but so does using a breaker that meets the equipment requirements for where it will be installed. Siemens identifies UL 489 as the applicable standard for the QPJ3125, which covers molded-case circuit breakers and related equipment.

The manufacturer's supplied information includes:

• Applicable Standard: UL 489
• REACH Information: Refer to the manufacturer's applicable substance-compliance documentation

Where It Works Best

• Existing Siemens QPJ Installations: Electrical equipment specifically approved for Type QPJ breakers.
  
• Like-for-Like QPJ3125 Replacements: Applications where the original breaker has the same catalog number, ratings, and connection type.
  
• Compatible Load Center Main Breaker Applications: Load centers designed to accept this 125-amp, three-pole plug-in configuration.
  
• Electrical Distribution Systems: Installations requiring a 240V AC breaker with a 10kA interrupting rating.
  
• Legacy Electrical Equipment Maintenance: Maintaining older systems that specify the Siemens QPJ3125.
  
• Three-Pole Circuit Protection: Equipment requiring thermal-magnetic protection across three poles.