The Siemens 5SY6463-8 is a SENTRON miniature circuit breaker (MCB) with a D tripping characteristic, rated 63 A at 400 V AC across 4 poles. Breaking capacity is 10 kA per IEC 60947-2, with a secondary 6 kA rating per EN 60898 for residential or light commercial coordination. DC rating is 15 kA at 72 V per IEC 60947-2, so it also handles DC-side faults on rectified supplies or battery banks.
Occupies 4 width units (72 mm) on the rail, with a depth of 76 mm and installation depth of 70 mm behind the panel face.
Halogen-free and silicon-free construction suits environments where outgassing or contamination is a concern — clean rooms, medical equipment, or sealed enclosures near sensitive electronics. Operating temperature range spans -40 °C to 75 °C, with humidity derating above 55 °C. Overvoltage category III (distribution-level) per IEC 60947-2. UL 1077 and CSA C22.2 No. 235 recognized at 5 kA for North American supplementary protection applications.