What this RCBO delivers on the panel
The Siemens SENTRON 5SU1353-7KL32 is a 2-pole RCBO (residual current circuit breaker with overcurrent protection) rated 32 A at AC with a C tripping characteristic — the standard choice for motor and lighting circuits where moderate inrush is expected. It combines overcurrent and residual current protection in a single 36 mm wide (2 modular width units) package, saving one DIN-rail position versus separate MCB+RCCD. Breaking capacity is 4.5 kA per EN 60898 and 5 kA per IEC 60947-2, sufficient for most commercial and light industrial distribution boards where the prospective fault current stays under 5 kA. The Type A residual current detection handles pulsating DC faults — common from electronics, rectifiers, and variable-speed drives — not just sinusoidal AC leakage. The 77 mm depth and 90 mm height fit standard SENTRON distribution boards and enclosures. Mounting position is unrestricted (any orientation), and the supply can enter from top or bottom — simplifies wiring in tight panels.
Thermal derating — what the numbers mean for your load
The 32 A rating holds at 30 °C ambient. At 40 °C it derates to 30.4 A, at 50 °C to 28.8 A, and at 70 °C to 24.64 A. Size the upstream load for the actual ambient temperature.
Integration and compliance
Rated for overvoltage category III and pollution degree 2 — standard for fixed-installation distribution boards. IP20 with connected conductors (the board enclosure provides the environmental seal). Halogen-free and silicon-free construction matters for clean-room or high-reliability environments where off-gassing can damage contacts or optics. The 70 mm installation depth (into the board) and touch-protected terminals (finger-safe) meet the requirements of modern distribution boards. Energy limitation class 3 means it limits let-through energy under fault conditions, helping with downstream coordination.