Vibration Sensor. Component Guide 4

VIBRATION-SENSOR-2An Ultra sensitive Vibration Sensor SW 18020 P is now available from the Gaoxin. It can be used in different ways to sense mechanical vibrations to activate alarms and other surveillance systems and a variety of vibration detection projects.
The Vibration sensor has two electrical contacts which are not connected in idle condition. When an external force is applied due to movement or vibration , the Sensor’s contacts close. When the force is removed, the sensor terminal returns back to open contacts. The internal spring closes the contacts during vibration which triggers the circuit connected to it.

How it works?
The sensor is made up of a small spring mechanism, which makes the contacts ON when a vibration force is applied above a certain threshold level. Two pins coming out of the sensor  are insulated by a resistance of more than 10 M Ohm. When a Vibration force is applied on the switch, the spring inside the switch vibrates and makes a momentary short circuit between the two terminals. The terminals of the Vibration sensor has no polarity but one pin is thick. Use it to connect to Vcc through a resistor and connect the thin pin to the circuit to be triggered.

How to Test?
Before using the Vibration sensor in Projects, test whether it is working properly or not. A simple LED circuit shown below can be used to test the Vibration sensor. Use the Sensor as a Switch for the LED circuit. After powering, gently tap on the sensor. LED will light momentarily and turns off. When the Sensor gets vibrations, its contacts close and gives current to LED and it glows. When the vibration ceases, contacts break and cut of power to LED.
1. Maximum supply voltage is 12 V DC but it works from 3-12 V DC.
2. Maximum current – Less than 5 Ma
3. Open circuit resistance – Higher than 10 Mega Ohms
4. On resistance – Less than 5 Ohms
5. Life expectancy – More than 5 Lakh times
6. Response time – 2 ms
The Vibration Sensor can be used in applications like Anti-theft alarm, Smart Home Systems, Automotive devices, Home electrical devices. Air condition blower fall prevention protect switches, Communication devices, Electronic scale, Meters, Robots, Toys etc.