Circuit breaker size S00 for transformer protection A-release 1.4...2 A N-release 42 A screw connection. Standard switching capacity circuit breakers SIRIUS 3RV2 for transformer protection to ensure safe protection of transformers against short circuits and overloads. The compact and climate-resistant circuit breakers are optimized for use in consumer branches due to their low heat dissipation, of course also for IE3/IE4 motors and equally for switching DC. Worldwide approvals (e.g., IEC and UL/CSA) and applications in explosion-hazardous environments (ATEX or IEC Ex) are standard. Device variants are available for motor protection (also with overload relay function), system protection, short-circuit protection of starter combinations, transformer protection, as main and emergency stop switches, and for use in IT networks. They come with screw or spring-loaded connections for quick, maintenance-free, and vibration-resistant connections, and optionally with built-in auxiliary switches. The comprehensive accessories, such as auxiliary switches, auxiliary releases, signaling switches, etc., are uniform across all sizes. The use of various energy supply options, such as the associated supply system SIRIUS 3RV29, significantly reduces the main circuit wiring. The 3RV2 circuit breakers replace the proven series 3RV1. Simple, efficient, always up to date - the SIRIUS system modular concept.