Siemens Q2125B 2 Pole Molded Case Circuit Breaker

Siemens Q2125B is a two-pole molded‑case circuit breaker from the QPP family, designed for 120/240 V service and rated at 125 A. It delivers up to 10 kA interrupting capacity at 240 V, providing robust protection for branch circuits and feeders in residential panels or light commercial installations that accept Siemens Q‑Series devices. The Q2125B uses a thermal‑magnetic trip mechanism to deliver long‑time protection and instantaneous response to overcurrent, and it is listed under catalog number Q2125B in the QPP line. In typical installations, the two poles operate together to disconnect both conductors on a fault, helping protect multiwire circuits and reduce arcing. This 2‑pole breaker is compatible with Siemens load centers that specify Q‑Series protection and is commonly used for high‑load circuits such as major appliance feeders, HVAC equipment, and other 125 A maximum loads in 120/240 V systems.