The Siemens 5SU9326-1CR20 is a 2-pole RCD-operated circuit breaker (RCBO) from the SENTRON series, combining overcurrent protection and residual current protection in a single 4-module-width unit.
Ratings and derating — what matters for fit
At 40 °C it derates to 18.6 A, at 45 °C to 17.6 A, at 50 °C to 17.2 A, and at 55 °C to 16.6 A.
Snaps onto DIN rail, occupies 4 modular width units (72 mm wide, 90 mm tall, 77 mm deep, 70 mm installation depth). Mounting position is any orientation. Supply can enter from top or bottom. The IP20 rating applies once installed in a distribution board with conductors connected — not for open-panel or wet-area use. Halogen-free and silicon-free construction suits environments sensitive to outgassing, such as clean rooms or medical facilities.