The Multimeters, also known as multiplex meters, multimeters, three-purpose meters, and multi-use meters, are indispensable measuring instruments for power electronics and other departments. Generally, voltage, current and resistance are the main purposes. The multimeter is divided into a pointer multimeter and a digital multimeter according to the display mode. It is a multi-functional, multi-range measuring instrument. The general multimeter can measure DC current, DC voltage, AC current, AC voltage, resistance and audio level, etc. Some can also measure AC current, capacitance, inductance and semiconductor and some parameters.

The measurement process of the digital multimeter is converted into a DC voltage signal by the conversion circuit, and the analog voltage is converted into a digital quantity by an analog/digital converter, and then counted by an electronic counter, and finally the measurement result is digital. Displayed directly on the display. The voltage, current and resistance functions are realized by the conversion circuit part, while the current and resistance measurement are based on voltage measurement, which means that the digital multimeter is extended on the basis of the digital DC voltage meter. When using a multimeter for measurement, pay attention to the safety of the personal and instrumentation equipment. It widely used in life. We have to be carefully when we use it, do not touch the metal part of the test pen by hand during the test. Do not switch the gear switch with power to ensure accurate measurement and avoid accidents such as electric shock and burning of the instrument. It widely used in life.