The Siemens SENTRON 5SY7616-8 is a 4-pole miniature circuit breaker (3P+N, neutral conductor switched) with a D tripping characteristic, rated 16 A at 35 °C and 50/60 Hz. The D-curve means it's built for loads with high inrush — motor circuits, transformers, welding gear — where the magnetic trip holds off until roughly 10–20× rated current.
This breaker carries a 15 kA rated short-circuit capacity per EN 60898 and 25 kA per IEC 60947-2. For DC circuits (up to 72 V max) it's rated 15 kA per IEC 60947-2. The EN 60898 number (15 kA) is the domestic/commercial rating; the higher IEC 60947-2 rating is the one an integrator uses for selectivity studies on a factory floor.
Thermal derating — don't ignore the fine print
Rated 16 A at 35 °C ambient, but the thermal curve drops steadily: 15.23 A at 40 °C, 14.83 A at 45 °C, 14.43 A at 50 °C, 14 A at 55 °C, 13.57 A at 60 °C. Pollution degree 3 (conductive pollution, typical for industrial environments) and overvoltage category III apply, so install it with the sealed cover option if the panel sees dust or moisture. IP20 with connected conductors is the base protection; the sealable feature (yes) lets you lock the toggle position.