The Siemens 5SU9356-7KK25 is a SENTRON RCBO — an RCD-operated circuit breaker combining overcurrent and residual current protection in a single 2-module-wide (36 mm) package. The 30 mA trip threshold covers personnel protection against direct contact; Type A means it catches pulsating DC residual currents from rectified loads like VFDs or LED drivers, not just sinusoidal AC.
Integration Notes
Touch-protected terminals (IP20 with connected conductors in an installed distribution board) meet finger-probe safety.
Thermal Derating & Environment
Derate linearly: 23.5 A at 40 °C, 22.75 A at 45 °C, 21.75 A at 50 °C, 20.25 A at 55 °C. Operating range -40 to 75 °C covers unheated enclosures and high-temp machine cabinets. Halogen-free and silicon-free construction suits clean-room or sensitive electronics environments where outgassing must be minimized.