The Siemens 5SY4214-8CC11 is a 2-pole miniature circuit breaker rated 400 V with a 10 kA breaking capacity, a D tripping characteristic, and a 0.3 A current rating, specifically designated for railway applications.
The D-curve magnetic trip handles inrush from inductive loads like contactors and relays. At 0.3 A it protects control circuits, signaling loops, or auxiliary supply taps. The 2-pole configuration switches both line and neutral for single-phase AC or DC control circuits.
This MCB is built for rail-vehicle and trackside panels where vibration, wide temperature swings, and DC auxiliary supplies are the norm. The D-curve and 0.3 A rating make it a common choice for protecting a 24 VDC control transformer secondary or a signaling relay bank in a locomotive electrical cabinet.
This order code is specified into the railway MCB slot.