Piezo Element (Vibration / Knock Sensor)

This basic Piezo Element measures 20mm accross and is a great little vibration sensor. Attach the round disc to the object that will be knocked on such as a door and measure the voltage across the two wires. Piezo elements can also produce sound when a voltage is applied across them. They convert between electricity and vibration in both ways; Vibration applied at the round end can be detected as a voltage across the wire leads and inversely, voltage applied across the wire leads causes the round end to vibrate.

Specifications:

• Piezo Element
• Disc Diameter: 0.79" (20mm)
• Wire Lead Length: 5.75" (146mm)
• Vpp: 30V AC
• Resonant frequency: 6.5 +/- 0.5KHz
• Resonant resistance: 300 ohms (Max.)