SIEMENS BQ3B050 Miniature Circuit Breaker 50A 3 Pole 240V AC

SIEMENS BQ3B050 50A Three-Pole Breaker

The SIEMENS BQ3B050 is a bolt-on miniature circuit breaker rated at 50 amps and 240 volts AC with three poles. It belongs to the BQ series and carries a 10kA interrupting rating at 240 volts AC. The unit fits Siemens panelboards and uses lug terminals for wire connections. It operates up to 104 degrees Fahrenheit and accepts wire sizes from 8 AWG to 4 AWG aluminum or 6 AWG copper.

Suited for three-phase panelboard circuits

This breaker suits electricians and maintenance teams wiring three-phase loads in Siemens panelboards where a 50 amp standard trip curve is specified. It is not for DC circuits, as the device carries no DC voltage rating. Buyers needing a different ampere rating, a different pole count, or a breaker for a non-Siemens panelboard should look elsewhere. Installations requiring a higher interrupting capacity than 10kA at 240 volts AC also fall outside this model's scope.

50 amp capacity with 10kA interrupting headroom

The breaker comfortably handles continuous loads up to its 50 amp rating within a 125 amp frame size. Its 10kA AIR rating provides adequate short-circuit protection for typical light-commercial and residential three-phase services at 240 volts AC. The lug terminals accommodate the listed wire range for secure connections. Headroom ends at the 10kA interrupting limit; systems with available fault current above that level require a breaker with a higher AIR rating.