RCD-operated circuit breaker, 6 A Type C, 30 mA Type A
The Siemens 5SU9356-7KP06 is a SENTRON RCBO combining overcurrent protection and residual current detection in a single 36 mm wide module. Rated 6 A with a Type C tripping characteristic, it handles inrush from motor starters and lighting ballasts without nuisance trips. The Type A residual current element detects pulsating DC fault currents up to 30 mA, covering electronics and variable-speed drives. Breaking capacity is 6 kA per EN 60898 and 10 kA per IEC 60947-2, so it clears line-to-neutral faults on a standard 230/400 V distribution board without upstream reinforcement.
Mounting and conductor range
Two width units (36 mm) snap onto a DIN rail. Accepts solid or stranded copper from 0.75 to 35 mm², which covers most final subcircuit feeds up to 6 A. Installation depth is 70 mm; the overall depth including terminals is 77 mm — check gland-plate clearance if the enclosure is shallow. Mounting position is any, so it fits vertical or horizontal busbar arrangements.
Thermal derating and ambient limits
Rated 6 A at 30 °C ambient. Derate to 5.64 A at 40 °C, 5.46 A at 45 °C, 5.22 A at 50 °C, and 4.86 A at 55 °C. The maximum ambient for operation is 45 °C; storage range is -40 to +75 °C. If the panel runs hot (e.g., enclosed drives or transformers nearby), size the upstream protection for the derated current, not the 30 °C figure.