The Siemens 5SU1354-7VK16 is a SENTRON RCBO (residual current circuit breaker with overcurrent protection) in a 2-module-width (36 mm) package, rated 16 A with a C tripping characteristic. It combines a Type A residual current device with a 10 kA breaking capacity per EN 60898 and 20 kA per IEC 60947-2. This is the Super resistant K design, meaning the housing and internals are built for higher ambient temperatures and aggressive atmospheres — halogen-free and silicon-free, so it won't outgas or corrode sensitive contacts in sealed enclosures.
Ratings and what they mean for your panel
The 16 A rating holds at 30 °C ambient, but drops to 15.2 A at 40 °C, 14.4 A at 50 °C, and 12.32 A at 70 °C. If your panel runs hot — say, a packed enclosure near a process line — you need to account for that derating curve. The C characteristic means it trips magnetically at 5 to 10 times rated current, so it handles motor inrush and transformer energization without nuisance trips, but still clears a hard short fast. Breaking capacity is 10 kA per EN 60898 (the residential / light commercial standard) and 20 kA per IEC 60947-2 (the industrial standard). That 20 kA figure is the one to use for industrial panel SCCR calculations — it tells you the device can safely interrupt a 20 kA prospective fault current at 230/400 V without welding or exploding. Overvoltage category III and pollution degree 2 are standard for fixed-installation distribution boards.
Physical fit and mounting
Width is 36 mm (2 modular units), depth 77 mm, height 90 mm, with an installation depth of 70 mm behind the panel face. Mounts on standard DIN rail in any position — top or bottom feed, your choice. The IP20 rating applies when installed in a distribution board with conductors connected; the device itself isn't rated for wet or dusty environments, so keep it inside the enclosure.