What it is and what it does
The Siemens 5SL3332-7 is a 3-pole SENTRON miniature circuit breaker rated 32 A with a C-curve trip characteristic, designed for AC circuits at 400 V nominal and up to 440 V maximum in multi-phase operation. Its breaking capacity is 4.5 kA according to EN 60898 and 5 kA per IEC 60947-2 — the higher IEC figure is what matters when the breaker sits in an industrial panel where the prospective fault current may exceed the residential standard. The C-curve means it trips between 5 and 10 times rated current, so it handles moderate inrush from small motor loads or transformers without nuisance tripping, while still clearing a hard fault fast enough to protect downstream wiring.
Where it fits and how it mounts
Occupies 3 modular width units (54 mm wide) on a standard DIN rail. Depth is 76 mm, installation depth 70 mm — leaves clearance behind the panel door for wiring and the sealable cover. Mounting position is any, so it works in vertical or horizontal DIN-rail orientation. Rated IP20 with connected conductors — fine inside a closed panel, not for wet or outdoor locations. Power loss per pole is 3.1 W at rated current in hot operating state. In a tightly packed enclosure with multiple breakers, that heat adds up — account for it in your thermal derating if the ambient exceeds 40 °C.
Lifecycle and sourcing
Rated for 10 000 mechanical operating cycles typical, which is standard for a residential/infrastructure MCB in this class. Overvoltage category III and pollution degree 2 suit it for fixed-installation distribution boards.