Method of measuring whether piezoelectric ceramics are damaged by multimeter
The multimeter consists of three main parts: meter head, measuring circuit and transfer switch. Multimeter is the most basic tool in the field of electronic testing, and it is also a widely used testing instrument. Multimeters are also called multi-meters, three-meter (A, V, Ω, that is, current, voltage and resistance), multi-meter and universal meter. Multimeters are divided into pointer multimeter and digital multimeter, and there is also an oscillometric multimeter with oscilloscope function, which is a multi-functional and multi-range measuring instrument.
General multimeters can measure DC current, DC voltage, AC voltage, resistance and audio level, and some can also measure AC current, capacitance, inductance, temperature and some parameters of semiconductors (diodes, triodes). Digital multimeter has become the mainstream and has replaced analog instruments. Compared with analog instruments, digital instruments have the advantages of high sensitivity, high accuracy, clear display, strong overload capacity, easy carrying and simple use. Let's let the electrician's house xiaobian introduce the method of using multimeter to judge whether piezoelectric ceramics are damaged.
Piezoelectric ceramics is a kind of synthetic piezoelectric material. When subjected to external pressure, charges will be generated on both sides, and the amount of charges is proportional to the pressure. This phenomenon is called piezoelectric effect. Piezoelectric ceramic has piezoelectric effect, that is, it will deform under the action of external electric field, so piezoelectric ceramic sheet can be used as sound element.
Using the piezoelectric effect of piezoelectric ceramics, it can be judged by multimeter.
Lead out two wires from the two poles of the piezoelectric ceramic piece, then put the ceramic piece flat on the table, connect the two wires to the two probes of the multimeter respectively, set the multimeter to the minimum current stop, and then gently press the ceramic piece with the pencil rubber head. If the pointer of the multimeter swings obviously, it means that the ceramic piece is intact, otherwise, it means that it has been damaged.
