The 5SL6304-7RC: The 4 A rating at 30 °C defines the continuous current the MCB carries without tripping. The 7.5 kA breaking capacity per EN 60898 tells you the MCB can safely interrupt a fault current up to 7.5 kA at 415 V AC without welding contacts or cascading failure upstream. EN 60898 is the residential and commercial standard; for industrial panels with higher prospective fault current, you would check the IEC 60947-2 rating on a different variant. IP20 with connected conductors means the front of the MCB is finger-safe, but the terminals are not sealed against dust or moisture — this is normal for a DIN-rail MCB inside a closed panel. The part is sealable for tamper-proofing in metering or critical circuits.
The 54 mm width corresponds to 3 modular units on a standard 18 mm DIN-rail grid, so it occupies three adjacent positions. Mounting position is any, which simplifies layout in crowded enclosures. Rated for residential and infrastructure use, the MCB handles final sub-circuits in lighting, socket outlets, and small equipment.