A piezoelectric sensor is a device that uses a piezoelectric effect to measure the changes in pressure, acceleration, temperature, strain, or force by converting them to an electrical charge.
Working principle
When a force is applied to a piezoelectric material, an electric charge is generated across the faces of the crystal. This can be measured as a signal or voltage proportional to the pressure.
Material Used
Two main sensing materials are used for piezoelectric sensors:
- Piezoelectric ceramics (such as PZT ceramic)
- Single-crystal materials (such as quartz).
The sensitivity of ceramic materials is superior to that of natural single-crystal materials. but their high sensitivity degrades over time.
Specifications
There are two types of piezoelectric sensor based on the connection design:
- Lead type
- Pin type
Their specifications are listed as:
| Parameter | Description |
| Operating voltage | 3 to 24 V |
| Rated voltage | 12 V |
| Rated current | 10mAmp |
| Resonant frequency | 3,5 kHz |
| Pin spacing | 15mm |
| Outer diameter | 23 mm |
| Min sound pressure level | 85 dB |
Advantages of Piezoelectric Sensor
- One of the main advantages of piezoelectric sensors is their ruggedness. This makes them suitable for use in a variety of harsh environments.
- Piezoelectric sensors can be used at high temperatures. They can work up to 1,000ºC.
- They are low-power devices since the output signal is generated by the piezoelectric element itself.
- The sensing element of a piezoelectric sensor is insensitive to electromagnetic interference and radiation.
- Piezoelectric sensors can be easily made using inexpensive materials
Applications of Piezoelectric Sensor
- They can be used in a wide range of industrial and aerospace applications where they’ll be exposed to high temperatures and pressures.
- They are frequently used for measuring dynamic pressure, for example in turbulence, blast, and engine combustion. These all require fast response, ruggedness and a wide range of operations.
- Their sensitivity and low power consumption make them useful for some medical applications.
