The Siemens SENTRON 3VA9137-0FK41 is a door-coupling rotary operating mechanism designed for the 3VA4/5 125 molded-case circuit breaker frame. It is the standard NEMA Type 4, 4X variant, meaning it carries an IP65 seal against hose-directed water and dust ingress, and includes both a door interlock and a door-open position accessory. The IP65 and NEMA 4/4X ratings mean this handle can be mounted on the enclosure door of a panel that sees washdown or outdoor exposure — the operator shaft seals against the door cutout, keeping the interior dry. The door interlock prevents opening the enclosure with the breaker closed, which is a standard safety requirement for motor-disconnect applications.
The mechanism measures 77 mm wide by 70 mm high. These are the panel-door cutout dimensions, not the overall handle projection. When specifying the door layout, the 77 mm width is the critical dimension — it dictates the horizontal clearance needed between the handle and any adjacent door-mounted devices.