Siemens 3SE3 120-1UW Position Switch

The Siemens 3SE3 120-1UW is a metal-enclosed safety position switch that delivers IP67 protection, snap-action contacts, and a roller-crank actuator with adjustable length. Designed for safety-related position sensing on industrial machinery, it uses a separate actuator and provides end‑of‑travel signaling for guarding, interlocking, and control circuits. As a member of the 3SE3 family, the device switches with fast, deterministic snap-action contacts, enabling quick response in safety circuits. The unit's wiring accommodates multiple conductors, with a maximum size of 2 x 2.5 mm² for solid conductors and 2 x 1.5 mm² for finely stranded conductors with core end sleeves. Its metal enclosure supports rugged environments and IP67 sealing, making it suitable for installations exposed to dust, water ingress, or washdown. The 120-1UW variant aligns with standard 3SE3 form factors and is designed for reliable position feedback on equipment such as guards, gates, and other safety interlocks, where knowing the exact switch state is essential for machine control.