What it is and what it does
The Siemens 5SU1354-7KK13 is a SENTRON RCBO — a combined residual-current circuit breaker with overcurrent protection — in a 1P+N, 2-pole format. It carries a 13 A rated current at 50 Hz with a C-curve tripping characteristic, meaning it handles moderate inrush from motor or lighting loads without nuisance trips, and a 30 mA Type A residual-current element that catches pulsating DC fault currents from electronics and single-phase rectifiers. The 10 kA breaking capacity per EN 60898 covers most commercial and light industrial panel fault levels.
Fit and integration
Two modular-width units (36 mm wide) snap onto standard DIN rail. Depth is 77 mm, installation depth 70 mm — verify enclosure depth before panel layout. Supply can enter from top or bottom. IP20 only once the distribution board is installed and conductors are connected; not rated for wet or dusty environments without an enclosure.
Thermal derating — the real-world rating
The 13 A rating holds at 30 °C ambient. At 40 °C it derates to 12.48 A, at 50 °C to 11.96 A, and at 65 °C to 10.53 A. If the panel runs hot — say 55 °C inside — the usable continuous current is 11.57 A, not the label value. Plan the load accordingly.