The Siemens 5SY4406-7CC is a SENTRON miniature circuit breaker (MCB) — 4-pole, C-curve, rated 6 A at AC, with a 10 kA breaking capacity per EN 60898. The IP20 rating applies with conductors connected, so it lives inside an enclosure, not exposed on the line side.
The C-curve (tripping characteristic C) means the magnetic trip fires at 5 to 10 times rated current — 30 to 60 A for this 6 A unit. Breaking capacity is 10 kA per EN 60898 and 5 kA per UL 1077 / CSA C22.2 No. 235. The 10 kA figure governs IEC panels; the 5 kA UL figure matters if the panel carries a cUL mark. Thermal derating is spelled out: 6 A at 35 °C, 5.51 A at 40 °C, 5.25 A at 45 °C, 4.97 A at 50 °C, 4.69 A at 55 °C. If the panel ambient runs 50 °C, size the load at 5 A, not 6.
Integration notes
Mounts in any position — vertical, horizontal, flat — with no derating for orientation. Touch protection is built in (finger-safe terminals with conductors connected). Environmental range: -40 °C to 75 °C operating, with humidity limits of 95% up to 55 °C, 55% up to 70 °C, 35% up to 75 °C.