Siemens B350EGHH GFEP Molded Case Circuit Breaker

The 50A rating is the breaker's rated current, not an instantaneous trip threshold. Use it when coordinating the circuit load, conductor ampacity and overcurrent protection.

This three-pole breaker is rated for a 208Y/120VAC three-phase system. The Y indicates a wye system, so match both the system configuration and voltage when selecting it.

The 65kAIC rating describes the breaker's ability to interrupt short-circuit current. Compare it with the available fault current at the installation point; the available fault current must not exceed the interrupting rating.

GFEP means ground-fault equipment protection. It addresses ground faults for equipment protection, so select it for that purpose rather than treating it as personnel ground-fault protection.

Both the thermal and magnetic trip settings are fixed. Thermal protection responds to sustained overloads, while magnetic protection responds rapidly to short-circuit current; select the breaker with those nonadjustable settings in mind.

Bolt-on mounting uses a bolted connection to secure the breaker electrically and mechanically. Installation requires fastening that connection securely before energizing.

The load-side connection uses lugs. Prepare and secure the outgoing circuit conductors in those lugs to make the load-side electrical connections.

Use the 60/75 °C conductor temperature rating when determining allowable conductor ampacity at the termination. Apply the appropriate temperature basis for the installation rather than relying only on the conductor insulation's temperature rating.