Siemens HNXD63B120H Circuit Breaker

This N-Frame breaker mounts directly into Siemens Sentron panelboards, P4 and P5 configurations, modular switchboards, and motor control centers. It is engineered for heavy-duty commercial or industrial setups requiring a 1200A main or feeder.

The thermal element provides continuous overload protection that is permanently fixed at 1200A. The adjustable magnetic dial allows electricians to set the exact instantaneous trip point for short circuits, which is critical for achieving selective coordination with downstream breakers.

Yes, it safely clears faults in DC distribution systems up to 250VDC and 500VDC. Electricians frequently deploy this model in industrial DC drives, heavy transit infrastructure, or battery backup configurations.

Both utilize the exact same ND-frame dimensions and bolt-on mounting hardware. The HNXD designation simply indicates a higher interrupting rating, making it the necessary replacement for facilities where the available fault current exceeds standard limits.

No. To prevent arc flash hazards, all trip adjustments must be completed while the equipment is fully de-energized. Always follow NFPA 70E guidelines and strict lockout-tagout procedures before removing any deadfront panels.

A unit-mount design means the breaker does not plug onto a live bus system. Instead, it requires physical hardware to bolt the unit securely onto the backpan or structural frame of the panelboard, utilizing included mechanical lugs for phase connections.