It protects a single-phase final subcircuit against overload, short-circuit, and earth leakage.
The 20 kA figure under 60947-2 gives headroom for installation close to a transformer or in high-fault locations where a standard 10 kA device might not coordinate. The insulation voltage (Ui) is 264 V, and surge voltage resistance is rated at 4 000 V, which is consistent with overvoltage category III — the usual level for fixed-installation distribution boards.
Thermal derating and installation
Rated 16 A at 30 °C ambient, the 5SU1354-7KK16 derates progressively: 15.2 A at 40 °C, 14.4 A at 50 °C, 13.6 A at 60 °C, and 12.32 A at 70 °C. Installation depth is 70 mm, and the overall depth including the front of the housing is 77 mm.
Compliance and approvals
Halogen-free and silicon-free construction. The housing is rated IP20 once installed in a distribution board with conductors connected. Pollution degree 2 (normal, non-conductive).