5MM Mercury Tilt Switch

From the shop's description

Mercury switches have one or more sets of electrical contacts in a sealed glass envelope that contains a small quantity of mercury. The envelope may also contain hydrogen at pressure, an inert gas, or a vacuum. Gravity constantly pulls the drop of mercury to the lowest point in the envelope. When the switch is tilted in the appropriate direction, the mercury touches a set of contacts, thus completing an electrical circuit. Tilting the switch in the opposite direction moves the mercury away from that set of contacts, breaking that circuit. Features: The contacts are enclosed, so oxidation of the contact points is impossible. In hazardous locations, interrupting the circuit does not emit a spark that could ignite flammable gases. Contacts stay clean, and even if an internal arc occurs, the contact surfaces renew on every operation, so they don’t wear out. Even a small drop of mercury has low resistance, so switches can carry useful amounts of current in a small size. The sensitivity of the drop to gravity provides a unique sensing function and lends itself to simple, low-force mechanisms for manual or automatic operation. The switches are quiet, as no contacts abruptly snap together. The mass of the moving mercury drop provides an over-center effect to avoid chattering as the switch tilts. Package Includes: 1 x Mercury Tilt Switch Operating Voltage (VDC) 3.3 ~ 5 Output Format digital switching outputs (0 and 1) Diameter (mm) 5 Length (mm) 35 Shipment Weight 0.01 kg Shipment Dimensions 8 × 7 × 1 cm