The Siemens 5SU9336-7CR40 is a 1P+N residual-current circuit breaker with overcurrent protection (RCBO) rated at 40 A with a C-trip characteristic, a 30 mA Type A residual sensitivity, and a 6 kA breaking capacity at 230 V AC. The C-curve means it holds up to 5–10× In (200–400 A) momentarily, sized for motor and lighting inrush without nuisance tripping. Type A residual detection covers pulsating DC fault currents from single-phase rectifiers — common in switched-mode power supplies and LED drivers found in modern control panels.
Snap-on mounting to standard DIN rail (EN 60715) — installs in a distribution board or sub-distribution panel alongside other 1P+N RCBOs and MCBs. The 1P+N form factor switches the line conductor and monitors neutral; the neutral bar is integral, so no separate N busbar connection is needed downstream. Rated 230 V AC single-phase, so it fits final subcircuits in lighting, socket-outlet, and small-load panels.