The structure, use and operating procedures of the multimeter
1. The basic structure and appearance of a multimeter
A multimeter mainly consists of three parts: an indicator, a measuring circuit, and a conversion device. The indicating part is usually a magneto electric microampere meter, commonly known as the meter head; The measuring part converts the measured electricity into a small direct current suitable for the meter requirements, usually including a shunt circuit, a voltage divider circuit, and a rectifier circuit; The measurement of different types of electricity and the selection of measurement ranges are achieved through conversion devices.
2. Instructions for using a multimeter
(1) The selection of terminal buttons (or sockets) should be correct
The red probe connecting wire should be connected to the red terminal (or the socket marked with a "+" sign), and the black probe connecting wire should be connected to the black terminal (or the socket marked with a "-" sign). Some multimeters are equipped with AC/DC 2500 volt measuring terminals, and when in use, the black test rod should still be connected to the black terminal (or the socket marked with a "-" sign), while the red test rod should be connected to the 2500 volt terminal (or the socket marked with a "-" sign).
(2) The selection of the switch position should be correct
Turn the conversion switch to the desired position according to the measurement object. If measuring current, the conversion switch should be turned to the corresponding current range, and the measured voltage should be turned to the corresponding voltage range. Some multimeters have two toggle switches on the panel, one to select the measurement type and the other to select the measurement range. When using, the measurement type should be selected first, and then the measurement range should be chosen.
(3) The range selection should be appropriate
According to the approximate range being measured, turn the conversion switch to the appropriate range for that type. When measuring voltage or current, it is recommended to keep the pointer within the range of half to two-thirds of the measuring range for more accurate readings.
(4) Read correctly
There are many scales on the dial of a multimeter, which are suitable for different measured objects. Therefore, when measuring, while reading on the corresponding scale, attention should also be paid to the coordination between the scale reading and the range range range to avoid errors.
