What this 4-pole MCB does in the panel
The Siemens SENTRON 5SJ6406-7 is a 4-pole miniature circuit breaker rated 6 A with a C tripping characteristic, meaning it's the go-to for moderate inrush loads like small motor starters, contactor coils, and banks of lighting — the C-curve holds past the short spike then trips fast on a hard fault. Breaking capacity sits at 6 kA per both EN 60898 and IEC 60947-2, so it's fine for residential and light commercial sub-distribution where the prospective fault current stays under that mark. At 400 V AC it covers three-phase line-to-line circuits; the 4-pole layout means it switches all three phases plus neutral in one compact 70 mm deep package that snaps onto DIN rail.
Terminal range and sealable cover — what that means on the route
Solid and stranded conductors from 0.75 mm² up to 25 mm² fit the terminals, which covers everything from control-circuit tails up to main feeder cable for a small sub-panel. The sealable feature (Yes on the nameplate) means the toggle cover accepts a lead seal or a lockout tag — out here in the grease that's what keeps the night-shift operator from resetting a breaker before you've cleared the fault. IP20 with connected conductors is standard for enclosed panels; no special washdown gaskets, so keep this one behind a gland plate.