Siemens Industry, Inc. BF1B030 U Circuit Breaker

Siemens BF1B030 U is a 30-amp, 120-volt, 1-pole molded-case circuit breaker from the BF1B/BF Series. This bolt-on device delivers thermal-magnetic protection with distinct long-time and instantaneous trip functions and a 10 kA interrupting rating at 120 V. It includes a built-in ground-fault interrupter (GFI/GFCI) and load-side lug terminals for straightforward wiring. Note that BF1B series breakers are cataloged as obsolete in newer Siemens literature, but the BF1B030 U model is still stocked by some distributors to service legacy panels and replacement needs. The compact 1-pole design is appropriate for protecting individual branch circuits in residential or light commercial panels, particularly for 120 V circuits where 30 A protection suits the load.