What it is — and what the ratings mean for fit
The Siemens SENTRON 5SY6163-7CC is a 1-pole miniature circuit breaker rated 63 A at 35 °C with a C tripping characteristic, meaning it handles moderate inrush currents from motor starters or transformers without nuisance tripping while still protecting branch circuits. Its 6 kA breaking capacity per EN 60898 is the standard for residential and light commercial distribution boards — adequate for most sub-distribution panels where the prospective short-circuit current stays under that threshold. The C-curve triggers between 5 and 10 times rated current, so it's the typical choice for general-purpose loads, not for high-inrush transformers (that's a D-curve job) or purely resistive loads (B-curve). At elevated panel temperatures the breaker derates: 59.22 A at 40 °C, 57.27 A at 45 °C, 55.19 A at 50 °C, and 53.05 A at 55 °C. If your enclosure runs hot — say a packed DIN rail in a non-ventilated cabinet — size the upstream protection for the derated value, not the 35 °C sticker.
Panel fit and mounting
Occupies 1 modular width unit (18 mm) on a DIN rail, with a depth of 76 mm and an installation depth of 70 mm behind the panel surface. The quick-assembly system snaps onto standard EN rail; mounting position is any, so vertical or horizontal rail orientation works. Touch protection is built in, and the terminals are combined top and bottom — wire from either direction without flipping the breaker. Sealable for tamper-proof installations (e.g., metering cabinets or rental panels). Halogen-free and silicon-free construction matters for environments sensitive to outgassing — clean rooms, medical, or semiconductor support areas.