What this RCBO is and what it protects
The Siemens 5SU1354-7LB10 is a SENTRON RCBO — a combined residual-current and overcurrent protective device in a single 2-module-width (36 mm) package, 1P+N pole configuration with one protected pole. It is designed for final circuits in distribution boards where both earth-leakage and short-circuit/overload protection are required in one unit, saving a DIN-rail position compared to separate RCCB and MCB. Rated 10 A at 30 °C with a C tripping characteristic (magnetic trip between 5 and 10 times In), it handles the inrush of motor starters, small transformers, and lighting ballasts without nuisance trips. The breaking capacity is 10 kA per EN 60898 and 20 kA per IEC 60947-2 — the higher IEC figure applies when the device is installed per the manufacturer's conditions, giving you headroom on high-fault panels. The design is marked "Short-time delayed G, super resistant K" — the residual-current element is a G-type (short-time delayed, typically 10 ms minimum non-tripping time) to avoid nuisance tripping from transient leakage pulses common on electronic loads, and the K suffix indicates enhanced immunity to surge currents (lightning or switching surges) without false operation.
Thermal derating — the real current rating at your panel temperature
The 10 A rating is only valid at 30 °C ambient inside the distribution board. Per the datasheet derating table, at 40 °C the continuous current drops to 9.5 A, at 50 °C to 9 A, at 60 °C to 8.5 A, and at 70 °C to 7.7 A. If your panel runs warm — common in crowded enclosures or near transformers — size the upstream protection and the connected load against the derated figure, not the 30 °C nameplate. Mounting position is any, which simplifies layout in tight enclosures. The installation depth is 70 mm (overall depth 77 mm including the front projection), fitting standard 80 mm deep distribution boards with room for wiring. Supply can enter from top or bottom — no orientation restriction for the line/load connection.
Environmental and compliance profile
Halogen-free and silicon-free construction — relevant for panels in clean rooms, semiconductor fabs, or any environment where outgassing from a fault could contaminate optics or sensitive surfaces. The operating temperature range spans -40 °C to 75 °C, covering cold storage and outdoor cabinet installations. Rated insulation voltage (Ui) 264 V, overvoltage category III, pollution degree 2 — standard for fixed-installation distribution boards in residential and light commercial buildings. The IP20 rating applies only when installed in a distribution board with connected conductors; the device itself is not touch-safe when removed from the enclosure.