The Siemens SENTRON 5SY7606-6 is a 4-pole miniature circuit breaker (3P+N) with a B tripping characteristic, rated 6 A at AC. It occupies 4 modular width units on a DIN rail and is designed for snap-on quick assembly in any mounting position. The B curve trips between 3 and 5 times rated current, making it the standard choice for resistive and general-purpose loads in commercial and industrial distribution boards — not for motor starting or high-inrush transformer circuits, where a C or D curve would be specified.
Breaking capacity and selectivity
Rated short-circuit breaking capacity is 15 kA per EN 60898 and 40 kA per IEC 60947-2. The 40 kA figure under 60947-2 is the industrial rating — it tells you this breaker can safely interrupt a fault up to that level without upstream devices needing to clear it. That matters for coordination studies: at 40 kA SCCR, this MCB can be the sole overcurrent device on a branch in a 400 V panel, provided the available fault current stays under that threshold. The energy limitation class 3 means it limits let-through energy during a short circuit, reducing stress on downstream wiring and connected equipment.
Thermal derating and ambient conditions
Rated 6 A at 35 °C ambient. Above that, derate linearly: 5.56 A at 45 °C, 5.41 A at 50 °C, 5.25 A at 55 °C, 5.09 A at 60 °C. If the panel runs hot — near a transformer or in a sealed enclosure — size the branch load against the derated figure, not the 6 A nameplate. Operating range spans -40 °C to 75 °C, with humidity limits of 95% up to 55 °C, 55% up to 70 °C, and 35% at 75 °C. Pollution degree 3 (conductive pollution or dry non-conductive that becomes conductive with condensation) is the rating for industrial control panels where the breaker sees the environment directly.
Physical fit and panel integration
Dimensions: 72 mm wide (4 MW), 90 mm high, 76 mm deep. Installation depth is 70 mm — the extra 6 mm is the front projection of the toggle and terminals. Combined terminals top and bottom accept busbar and conductor in the same clamp. IP20 with connected conductors, so it's protected against finger contact but not against water ingress — standard for enclosed distribution boards. Touch protection is integrated (fingertip-safe terminals). Halogen-free and silicon-free construction matters for environments where outgassing contaminates sensitive electronics or clean-room processes.