The Siemens 5SY4210-8CV is a miniature circuit breaker (MCB) with a D10 tripping characteristic, rated for a 10 A load current. Its interrupting capacity is 15 kA at 400 V, which means it can safely clear a fault up to that level without welding its contacts or cascading failure upstream in a distribution board. The D curve is designed for loads with high inrush currents — motor starters, transformers, or discharge lighting — where the magnetic trip threshold is higher than a B or C curve to avoid nuisance tripping on startup.
Integration and deployment
The 5SY4210-8CV snaps onto standard DIN rail in a panel or enclosure. The 2-pole form factor occupies two modular-width positions. The D10 curve and 15 kA SCCR suit it for motor branch circuits or transformer primary protection where the inrush exceeds what a C-curve breaker would tolerate without tripping.