Siemens BQ2B125 Molded Case Circuit Breaker

The BQ2B125 is designed for use in compatible Siemens and legacy ITE bolt-on panelboards that accept BQ frame breakers. It is not interchangeable with plug-on load center breakers.

The integrated load-side lugs accept 8 to 1 AWG copper wire or 6 to 1/0 AWG aluminum wire. Always torque the terminals to the manufacturer specifications printed on the breaker label.

This breaker features a bolt-on mounting style. It bolts directly to the panelboard bus bar, providing a secure, vibration-resistant mechanical and electrical connection that minimizes hot spots in high-draw circuits.

Yes, this breaker is HACR rated. It is certified for use with heating, air conditioning, and refrigeration equipment that involves motor-driven loads.

No, this is a standard thermal-magnetic branch circuit breaker. It provides essential protection against sustained overloads and short circuits but does not include GFCI or AFCI technology.

No, the BQ2B125 is a bolt-on breaker intended for commercial and industrial panelboards. Standard residential load centers typically require plug-on breakers, such as the Siemens QP series.

The 10kAIC rating indicates the maximum fault current the breaker can safely interrupt at 120/240VAC without sustaining damage. You must verify that your system's available fault current does not exceed 10,000 amps before installation.

While both are bolt-on breakers used in Siemens panelboards, BQ breakers like the BQ2B125 are rated for 120/240VAC or 240VAC systems. BQD breakers are rated for higher voltage systems up to 480Y/277VAC. They are not interchangeable if the system voltage exceeds 240V.

The common-trip design ensures that an overcurrent or short-circuit event on either pole will simultaneously disconnect both legs of the circuit. This prevents single-phasing on 240V equipment like compressors and motors.