Eaton / Cutler-Hammer FDB3100 Molded Case Circuit Breaker

While all three models share the same 100-amp rating and Series C F-Frame dimensions, they have different short-circuit interrupting ratings (AIC). The FDB3100 is rated for 14kA at 480VAC, the FD3100 is rated for 35kA, and the HFD3100 provides up to 65kA. You must verify your equipment's required fault current rating before selecting a breaker.

You should only replace an FD3100 with an FDB3100 if you have verified that the available fault current at that specific panel is 14kA or less at 480VAC. Because the FD3100 has a higher 35kA interrupting rating, installing an FDB3100 in a system that requires 35kA creates a severe hazard.

Yes. Eaton acquired the Cutler-Hammer and Westinghouse distribution equipment lines. The current Eaton FDB3100 is a direct, drop-in replacement for legacy Westinghouse and Cutler-Hammer FDB3100 breakers, fitting the exact same bolt-on mounting hardware.

Yes, the FDB3100 comes from the factory equipped with standard pressure load and line terminals. These lugs are dual-rated to accept both copper (Cu) and aluminum (Al) wire.

No. This model features a fixed thermal and fixed magnetic trip unit. It provides standard Long-Time and Instantaneous (LI) protection but does not have dials for field adjustments to the trip curves.

No. This is strictly a bolt-on molded case circuit breaker designed for commercial and industrial Eaton Series C panelboards, motor control centers, and switchboards. It will not fit into standard residential plug-on panels.

Installation requires standard hand tools to secure the bolt-on connections to the panel bus bars and to tighten the terminal lugs. Always ensure the lug torque values meet the manufacturer specifications found on the breaker label to prevent arcing and overheating.