The Siemens 5SY7402-7 is a SENTRON 4-pole miniature circuit breaker with a C-curve trip characteristic, rated 2 A at 400 V AC. It carries a 15 kA breaking capacity per EN 60898 and 50 kA per IEC 60947-2, giving it headroom for high-fault installations like industrial panel feeders or distribution sub-mains.
The 15 kA rating under EN 60898 covers the standard domestic/commercial fault level; the 50 kA under IEC 60947-2 addresses industrial installations where the prospective short-circuit current at the panel is higher. That dual rating means the same MCB satisfies both a building-services spec and a machine-control cabinet spec without swapping parts.
Snaps onto DIN rail via the quick assembly system; 4 modular width units (72 mm wide) occupy four 18 mm slots. Mounting position is unrestricted, so it can be installed vertically, horizontally, or flat in a panel without derating the 2 A rating.
Thermal derating and environment
Rated 2 A at 35 °C ambient; derates to 1.9 A at 40 °C, 1.85 A at 45 °C, 1.8 A at 50 °C, 1.75 A at 55 °C, and 1.7 A at 60 °C.