The B340GFHH is a 3-pole Class A ground-fault circuit interrupter (GFCI) circuit breaker from Siemens, engineered for commercial and industrial branch-circuit applications requiring both overcurrent protection and personnel-level ground-fault protection. Rated for 40 at 120, this bolt-on breaker combines conventional circuit protection with sensitive ground-fault detection to help protect personnel from hazardous leakage-current conditions. Electrically, the B340GFHH provides Class A GFCI protection with a 5 mA ground-fault trip threshold and is designed to de-energize all ungrounded conductors when a qualifying ground-fault condition is detected. It carries an interrupting capacity of , providing high short-circuit interrupting performance for compatible Siemens distribution systems with elevated available fault current. Its combination of overcurrent protection and personnel-level ground-fault sensing makes the B340GFHH well suited for branch circuits where enhanced electrical safety and high fault-current capability are required. Mechanically, the B340GFHH uses a bolt-on mounting configuration for secure installation in compatible Siemens panelboard and distribution equipment. Its 3-pole construction supports 120 applications while providing simultaneous disconnection of all protected ungrounded conductors during qualifying overcurrent or ground-fault events. Siemens specifies load-end terminals for this amperage range accepting #14–#6 AWG copper or #12–#6 AWG aluminum conductors using 60/75°C wire, supporting reliable field termination in commercial and industrial installations. Purchase the B340GFHH at Electrical.com, your reliable partner for industrial and commercial electrical products. Our selection includes trusted circuit breakers, GFCI protection devices, and power distribution components from manufacturers like Siemens, Eaton, Cutler-Hammer, and Schneider Electric, backed by a knowledgeable sales team ready to assist with technical questions, product selection, and support.