The Siemens 5SN6432-7CP is a 4-pole miniature circuit breaker from the SENTRON 5SN family, rated for 400 V AC supply at 50 Hz.
Four poles let you switch all three phases plus neutral in a single DIN-mounted unit — common for three-phase sub-distribution or for isolating a machine supply where the neutral needs to be broken. The 6 kA (EN 60898) rating covers most commercial service-entrance scenarios; the higher 15 kA (IEC 60947-2) figure gives you headroom for industrial fault currents upstream of a transformer or a large motor drive. On the DC side, it's rated to 72 V maximum, which makes it usable in some control-circuit or battery-backed applications, though it's primarily an AC breaker. Solid conductors up to 35 mm² can be terminated directly, which is enough for most sub-feed circuits.
Temperature range and mounting
The 76 mm depth and 72 mm width (4 modular width units) are standard DIN-rail dimensions — it clips onto a 35 mm rail and occupies 72 mm of rail space.