What it is and where it fits
The Siemens 5SY4414-7 is a 4-pole SENTRON miniature circuit breaker with C-curve tripping, rated 0.3 A at 400 V AC. It's designed for overcurrent protection of small motor feeders, lighting circuits, or control transformers in industrial panels where the load draws under 0.3 A per phase. C-curve handles moderate inrush — think small solenoid valves or contactor coils — without nuisance trips. The 4-pole frame gives three switched phases and a solid neutral (neutral switching is not active on this variant). Mount in any position, fits a standard DIN rail with quick-assembly fastening. Combined terminals top and bottom simplify daisy-chaining in distribution blocks.
Breaking capacity — what the numbers mean for your panel
Pollution degree 3 and overvoltage category III mean it's rated for fixed installations where transient overvoltages from the supply side are expected — typical for industrial switchgear.
Installation notes
Mounts in any orientation on 35 mm DIN rail. The 4 modular width units (72 mm wide) take up four positions on a standard distribution board. Combined terminals top and bottom accept the same busbar or fork connector, simplifying panel wiring. Depth 76 mm (70 mm installation depth behind the panel face) leaves clearance under standard enclosure depths. Touch protection is integrated — no need for additional finger-safe shrouds in most assemblies. Vibration resistance tested per IEC 60068-2-6: ±1 mm at 5-25 Hz, 50 m/s² at 25-150 Hz. Reliable in panels mounted on machinery or in mobile equipment.