Siemens HFXD63B225 Molded Case Circuit Breaker

This bolt-on circuit breaker is designed for use in Siemens P2, P3, S4, and S5 panelboards. It installs directly onto the panelboard bus using standard bolt-on connections.

The HFXD63B225 is the high-interrupting version of the standard FXD63B225. Both share the same physical FD frame footprint and 225A rating, but the HFXD63B225 provides higher short-circuit protection with ratings of 65kAIC at 480V and 25kAIC at 600V, compared to the standard model's 35kAIC and 22kAIC respectively.

No, this breaker is typically supplied without line and load lugs installed. If you are not bolting directly to a panelboard bus that already has landing pads, you must purchase the appropriate lug kits separately.

For standard copper or aluminum wire, use the TA1FD350A aluminum lug kit, which accepts 6 AWG to 350 kcmil conductors. If a copper-only connection is required by your specification, use the TC1FD350 copper lug kit for the same 6 AWG to 350 kcmil wire range.

Yes, this thermal-magnetic circuit breaker is rated for DC applications up to 500VDC with an interrupting capacity of 25kAIC. Always follow Siemens wiring configuration guidelines for series-wiring poles when used on direct current circuits.

The LI trip code indicates that this thermal-magnetic breaker includes Long-Time (L) and Instantaneous (I) protection functions. The Long-Time thermal trip provides standard overload protection and is fixed, while the Instantaneous magnetic trip provides short-circuit protection and is adjustable to coordinate with your system's load characteristics.

The instantaneous magnetic trip setting on this 225A breaker can be adjusted from 1100A to 2500A. This allows installers to fine-tune short-circuit protection to accommodate specific motor inrush currents or selective coordination requirements.

Yes, Siemens acquired the ITE product line and continues to manufacture these FD frame breakers under the same catalog numbers. A new Siemens HFXD63B225 is a direct, drop-in replacement for a legacy ITE HFXD63B225 of the exact same specification.