The Siemens 3SE5112-1QV10 is a SIRIUS mechanical safety switch with positive-opening contacts — the kind you wire into the guard-door circuit on a machine tool or conveyor cell. Two safety-related switching contacts give you the redundancy a Category 3 or PL d circuit expects, and the slow-action mechanism means the contacts open positively when the actuator leaves the head, no spring bounce. The 0.05 mm repeat accuracy tells you the switch lands in the same electrical state every time the guard closes — that matters when a PLC is watching the feedback for a stuck-contact fault. Housing is metal with a cathodic dip coating and IP66/IP67 sealing, so it survives washdown cycles in food plants or the grit on a sawmill line. The single M20 x 1.5 cable entry keeps the gland plate clean — one hole, one cable, no adapter plate needed. Screw terminals accept 1x (0.5 to 1.5 mm²) solid or 2x (0.5 to 0.75 mm²), which covers the typical 0.75 mm² or 1.0 mm² safety-circuit wiring from the guard switch back to the safety relay.
Thermal current (Ith) is 10 A, and the rated switching current at 24 V is 3 A. The insulation voltage is 400 V with a surge withstand of 0.8 kV, which puts it solidly in the industrial control panel range (pollution degree 3 per). The switch is designed for use with a separate actuator — the evidence lists nine compatible actuators including standard, vertical-mount, horizontal-mount, radius, universal, heavy-duty, plastic, and stainless steel variants. That means you order the actuator separately to match your guard-door geometry. The switch body itself has no actuating element built in; it's just the head and the contacts.
Lifecycle stage is marked current, meaning Siemens still lists this as an active catalog number.