The Siemens 5SU9354-8KK63 is a SENTRON 5SU9-series RCD-operated circuit breaker — an RCBO combining overcurrent protection and residual-current detection in a single 36 mm-wide module. The D tripping curve handles inrush from motor and transformer loads without nuisance trips.
At 40 °C derate to 59.22 A, at 45 °C to 57.33 A, at 50 °C to 54.81 A, and at 55 °C to 51.03 A. Operating ambient range is -25 to +45 °C; storage range -40 to +75 °C. The 1.5 W maximum power dissipation matters for enclosure thermal budgeting when multiple units are ganged.
Installation and wiring
Two-pole 1P+N unit, 36 mm wide (2 width units), 90 mm tall, 77 mm deep with 70 mm installation depth. Touch protection is built in. Halogen-free and silicon-free construction.
Listed as current production. This is an active SENTRON catalog line — no phase-out or last-time-buy notice on record.