The Siemens 3VA9987-0KB00 is a SENTRON position signaling switch accessory designed for plug-in and draw-out units. It carries a 6 A thermal current rating (Ith) and is rated for AC-12 duty at 6 A across 12 V to 240 V, and DC-12 duty from 6 A at 12 V down to 0.25 A at 250 V. Overvoltage category III and pollution degree 3 mean it's built for fixed-installation mains circuits where transient overvoltages and conductive dust are expected — typical for industrial control panels housing SENTRON molded-case breakers.
Integration Note
The 8.5 mm width and 33 mm depth let it fit into a standard DIN-rail enclosure alongside SENTRON breakers. Stripped length is 15 mm (0.6 in) for the screw terminals. The surge voltage resistance of 4 kV matches the insulation coordination of the breaker compartment it signals.