The mechanical linkage in a circuit breaker is often described as what component, also referred to as the actuating arm or lever?

• A. Linkage
• B. Armature
• C. Lever
• D. Cam

Answer: (A)

The movement from the operating mechanism to the actual contact assemblies in a circuit breaker is carried through a set of interconnected bars and pins—the mechanical linkage. This assembly transmits and coordinates motion, providing the proper path and timing for opening or closing the contacts, and it often includes an actuating arm or lever as part of that chain. The armature is a separate magnetic component that can actuate movement in some designs, the lever is just a single piece within the linkage that helps change the direction or magnitude of motion, and a cam is a rotating part used to convert rotation into linear motion in other mechanisms. Because the question describes the whole connecting system that transfers actuation to the contact parts, the term that fits best is linkage.