Eaton / Cutler-Hammer KB3100 Molded Case Circuit Breaker

Yes, this K-Frame breaker is compatible with Eaton Series C panelboards, as well as legacy Westinghouse CDP panelboards, switchboards, and motor control centers.

The KB3100 comes equipped with standard load side lugs that accept 3 AWG to 350 kcmil aluminum or copper (Al/Cu) wire. If your application requires different terminations, specialized lug kits must be sourced separately.

The KB3100 is a bolt-on circuit breaker. It secures directly to the panelboard bus using bolted connections, providing a secure and reliable termination for industrial applications and motor control centers.

The thermal magnetic trip unit features a fixed thermal element for long-time overload protection and an adjustable magnetic element. This allows panel builders to fine-tune the instantaneous short-circuit response for specific motor control or distribution loads.

The LI designation indicates that the breaker provides Long-Time and Instantaneous protection. The long-time function protects against sustained overloads, while the instantaneous function protects against short circuits.

Yes. Eaton acquired the Westinghouse distribution equipment division and continued manufacturing the Series C K-Frame under the Cutler-Hammer and Eaton brands. A KB3100 from any of these brands is physically and electrically identical and will fit the same panelboards.

According to Eaton cross-reference guides, the JD3100 is the modern Series C replacement for the obsolete KB3100. Note that upgrading to a newer frame style may require deadfront or mounting hardware modifications in older Westinghouse enclosures.