D-curve MCB for motor and transformer circuits
The Siemens 5SY7320-8 is a 3-pole miniature circuit breaker from the SENTRON series, with a D tripping characteristic rated at 20 A. Breaking capacity is 15 kA per EN 60898 and 25 kA per IEC 60947-2, giving it headroom for industrial panels where fault current can exceed the residential standard. At DC per IEC 60947-2 it still interrupts 15 kA. Rated current derates with ambient temperature: 20 A at 35 °C, 19.04 A at 40 °C, 18.54 A at 45 °C, 18.04 A at 50 °C, 17.5 A at 55 °C, and 16.96 A at 60 °C.
Occupies 3 modular width units (54 mm) on a DIN rail, with a depth of 76 mm and an installation depth of 70 mm. Mounts in any position — no orientation restriction for vertical or horizontal rail layouts.