The Siemens 5SY4416-6CC11 is a miniature circuit breaker (MCB) rated for 400 V with a 10 kA breaking capacity, 4-pole configuration, B-curve trip characteristic, and 16 A rated current, specifically designated for railway applications.
The 4-pole version (3 phases + neutral) covers three-phase loads or a mixed single-phase/three-phase distribution board.
