Square D Legacy Circuit Breakers FA/FH/FC/FI, KA/KH/KC/KI, LA/LH/LC/LI, MA/MH, NA/NC, PA/PC and Q-Frame This document is current but may reference obsolete products.

This document contains technical information for legacy thermal-magnetic and magnetic only molded case circuit breakers. Included topics: explanation of thermal trip and magnetic tripping conditions, mechanical lugs, crimp lugs, tripping characteristics and trip curves (time-current curves), let-through curves, circuit breaker endurance data, interrupting ratings tables, catalog numbering tables, and dimension drawings for approximate dimensions.