Siemens 3RV1421-0EA10 is a transformer-protection molded-case circuit breaker (size S0) designed to guard transformers from overloads and short circuits. It uses an A-release current element with a trip range of 0.28–0.4 A and includes a magnetic short-circuit release specified at 8.2 A, with screw-terminal connections for secure wiring. Listed as part of the Siemens 3RV family, this device is noted as the predecessor to the Sirius 3RV2 line, with 3RV2411-0EA10 identified as a possible successor, and is intended for transformer protection applications with standard switching capacity.
