The Siemens 5SU9356-1KX06 is a SENTRON RCBO — a combined residual-current device and miniature circuit breaker in a single 2-module-wide (36 mm) package. It protects a single-phase final subcircuit against both overload/short-circuit (6 A, Type C characteristic, 6 kA breaking capacity per EN 60898) and earth leakage (30 mA, Type AC residual current). The 1P+N design switches the live conductor and disconnects the neutral; the protected pole is the live side. This unit is rated for 50/60 Hz networks with an insulation voltage of 264 V and overvoltage category III, making it suitable for fixed-installation distribution boards in residential or light commercial panels. The 30 mA trip threshold covers basic shock protection and fire prevention for general-purpose socket outlets and lighting circuits.
Temperature derating and installation constraints
The 6 A rating holds at 30 °C ambient; at 40 °C it derates to 5.64 A, at 45 °C to 5.46 A, at 50 °C to 5.22 A, and at 55 °C to 4.86 A. If the distribution board runs warm — say, tightly packed with downstream loads — the effective continuous current is lower than the label value. Account for the derating curve when sizing the circuit. Mounting position is unrestricted, and the supply can enter from either the top or bottom. The unit occupies 2 modular width units (36 mm) on a DIN rail; installation depth is 70 mm, overall depth 77 mm. Pollution degree 2 applies (non-conductive pollution only, occasional condensation). The enclosure rating is IP20, conditional on the distribution board being installed with conductors connected. That means the RCBO itself is touch-safe only when mounted inside a closed panel — it is not rated for exposed or outdoor installation.