The Siemens 5SU1656-0KK16 is a 2-pole (1P+N) SENTRON RCBO — a combined miniature circuit breaker and residual current device in a single 36 mm wide (2 MW) module. It protects a 230/240 V AC circuit at 50 Hz, rated 16 A at 30 °C with a B tripping characteristic, and detects AC residual currents. That 15 kA rating gives you headroom in a sub-distribution board fed by a larger transformer — a common spec for packaging lines and conveyor systems.
Feed can come from top or bottom — no orientation restriction. Installation depth is 70 mm into the distribution board.
Thermal derating — what the numbers mean
In a warm panel — say 50 °C — the continuous current drops to 14.4 A. At 70 °C it's 12.32 A. If you're packing this RCBO next to other heat sources in a sealed enclosure, use the 50 °C or 60 °C column for your load calculation, not the 30 °C headline number.
Construction is halogen-free and silicon-free — relevant if the panel goes into a clean-room or semiconductor-adjacent environment where outgassing matters.