The Siemens 5SU9356-7KM10 is a SENTRON RCBO — an RCD-operated circuit breaker combining overcurrent and residual current protection in a single 2-module (36 mm wide) package. It's rated 10 A with a C tripping characteristic and Type A fault current sensitivity, covering sinusoidal AC and pulsating DC residual currents. Breaking capacity is 6 kA per EN 60898 and 10 kA per IEC 60947-2, so it handles typical domestic and light commercial fault levels without cascading upstream.
Ratings and what they mean for fit
The 10 A rating is the continuous current at 30 °C ambient. Above that, derate: 9.4 A at 40 °C, 9.1 A at 45 °C, 8.7 A at 50 °C, and 8.1 A at 55 °C. If your panel runs hot — say, a crowded enclosure near a conveyor drive — the 40 °C figure is the one to size against. The C-curve means the magnetic trip fires at 5–10× In (50–100 A), suited for motor-start or transformer inrush where a B-curve would nuisance trip. Type A residual current detection covers both sinusoidal AC faults and pulsating DC — common with single-phase rectified loads like switched-mode power supplies or LED drivers. The 1P+N configuration protects one phase conductor; the neutral is switched but not protected against overload. Overvoltage category III means it's rated for fixed-installation downstream of the main distribution board. Conductor cross-section range is 0.75 to 35 mm² for both solid and stranded, covering everything from small control wiring to heavy feeder tails. Power loss at rated current is 1.5 W — negligible for thermal budgeting in a multi-way board.
Mounting and integration
Snaps onto standard DIN rail. Width is 36 mm (2 width units), depth 77 mm, installation depth 70 mm. Mounting position is any orientation. Supply can enter from top or bottom — no mandatory orientation. IP20 with connected conductors and installed in a distribution board, so it's for enclosed use only, not washdown areas. Halogen-free and silicon-free construction matters if this goes into a clean environment or a panel with sensitive contacts. Touch protection is built in on the line side.