The Siemens 3RV1926-2B is a SIRIUS door-coupling rotary operating mechanism designed for heavy-duty operating conditions with circuit breakers of size S0. It allows the breaker to be operated from outside an enclosed panel through a door-mounted rotary handle, keeping the arc chamber sealed inside the enclosure during switching. The mechanism uses screw fixing for panel mounting and can be installed in any orientation. It measures 75 mm wide by 75 mm tall by 78 mm deep, with an overall length of 300 mm including the shaft and coupling hardware.
This part is in a product phase-out status. The preferred successor is the 3RV2926-3B, which carries a different drilling pattern — so a panel cutout modification will be required when transitioning. The operating mechanism is rated for up to 151 switching operations per hour, with an operating temperature range of -20 to +70 °C and a storage range of -50 to +80 °C. The gray actuating element is the standard design variant.