What it is and what it fits
The Siemens 3VA9138-0CB10 is a SENTRON accessory — specifically a Bowden wire actuator, listed as an operating unit with a Bowden cable Max Flex operator switching mechanism. It is a single accessory designed for the 3VA5 125 molded-case circuit breaker frame.
Deployment context
This Bowden wire actuator mounts to the 3VA5 125 breaker frame, allowing remote mechanical operation of the switching mechanism via a flexible cable. It is used in panel or enclosure layouts where the breaker must be actuated from a door, cover, or remote location without running control wiring — common in machine tool, conveyor, and process line disconnect applications.