Vibration Sensor: Advantages and Disadvantages

This page explores the advantages and disadvantages of vibration sensors, covering different types such as Pin and Spring, Piezoelectric, Accelerometer, Velocity Sensor, and Proximity Sensor.

What is a Vibration Sensor?

• Vibration sensors are used to measure, display, and analyze frequency, displacement, velocity, or acceleration related to repetitive mechanical motion.
• They typically have normally open contacts that close when subjected to vibration within their designed frequency range.
• Mechanical sensors (switches) that respond to displacement are best suited for low-frequency vibrations.
• Piezoelectric sensors are sensitive to acceleration and are better suited for high-frequency vibrations.
• Accelerometers measure acceleration to determine vibration.
• Proximity sensors are non-contacting sensors that measure distance from a target, often used in rotating machinery to measure shaft vibration.

• Vibration sensors are used in various applications to prevent further damage due to vibrations and can also be used as shock sensors.
• Different types include pin and spring, piezoelectric, piezoresistive, chip-based piezoelectric, mousetrap, magnetic, mercury, and accelerometers.
• The advantages and disadvantages vary based on the specific type.
• For more information, refer to articles on vibration sensor basics and types.

Benefits or Advantages of Vibration Sensors

Here are the benefits associated with different types of vibration sensors:

• Pin and Spring type:
  • Low cost.
  • Ability to respond to vibration in two out of three axes.
  • No power supply requirement.
  • Ability to switch DC or AC.
• Piezoelectric type:
  • Resonant frequency of approximately 170 Hz without added weight.
• Accelerometer:
  • High temperature tolerance.
  • Good response at higher frequencies.
  • Small size and easy installation.
• Velocity sensor:
  • Good response in the mid-range of frequencies.
  • Does not require external power.
  • Withstands high temperatures.
  • Easy to install and lower cost.
• Proximity sensor:
  • Precise response at lower frequencies.
  • No wear.
  • Smaller in size.
  • Lower cost.
  • Measures static and dynamic displacements.

Drawbacks or Disadvantages of Vibration Sensors

Here are the drawbacks associated with different types of vibration sensors:

• Pin and Spring type:
  • Requires latching components such as a flip-flop or 555 timer due to the brief internal contact duration.
• Piezoelectric type:
  • Generates voltage during deflection, but the output diminishes to zero when held in a curved position.
• Accelerometer:
  • Sensitive to higher frequency noise.
  • Requires external power.
• Velocity sensor:
  • Lower resonant frequency.
  • Bigger size and higher weight.
  • Susceptible to cross noise.
• Proximity sensor:
  • Susceptible to electrical and mechanical noise.
  • Not calibrated for unknown metals.
  • Requires external power.
  • Difficult to install.
  • Limited by higher frequencies.