The Siemens 5SU9106-1KK40 is a SENTRON 5SU9-series RCD-operated circuit breaker — an RCBO combining overcurrent protection and residual current detection in a single 1P+N package. Rated 40 A at 30 °C with a C tripping characteristic, it breaks fault currents up to 6 kA per EN 60898 and IEC 60947-2.
Current derating and ambient limits
Above that, derate per the published curve: 37.6 A at 40 °C, 36.4 A at 45 °C, 34.8 A at 50 °C, and 32.4 A at 55 °C. The maximum operating ambient is 45 °C, so the 36.4 A figure is the effective limit for a panel running at its upper temperature spec. Storage range is -40 to +75 °C.
Power supply can enter from either the top or bottom. Touch protection is included per the design.
Overvoltage category III. Energy limiting class 3. The product designation per DIN EN 61346-2 and DIN EN 81346-2 is F. The RCBO is designed for AC fault currents only.