Correct Usage Methods and Precautions for Analog Multimeters
Connect the wires correctly. Due to the fact that the DC meter head used in the multimeter only allows current to flow in from the "+" pole and out from the "one" pole, the sockets and terminals on the multimeter panel are marked with polarity. When in use, connect the red probe to the "+" polarity socket and the black probe to the "-" polarity socket. When measuring DC voltage and DC current, it is important to note that the polarity of the positive and negative probes should not be reversed to prevent pointer reversal. If pointer reversal is found, the probes should be replaced immediately. When measuring current, the instrument should be connected in series with IPP45N06S3L-13 in the tested circuit; When measuring voltage, the instrument should be connected in parallel at both ends of the tested circuit. When measuring transistors with a multimeter, it should be remembered that the red probe of the multimeter is connected to the negative terminal of the internal battery, and the black probe is connected to the positive terminal of the internal battery.
Choose the measurement gear correctly. The measurement gear includes the measurement object and range. When measuring voltage, the conversion switch should be placed in the corresponding voltage range, and when measuring current, it should be placed in the corresponding current range, etc. Misusing the current mode to measure voltage can cause damage to the instrument. When selecting the current or voltage range, the pointer should be positioned at 2/3 or more of the scale; When selecting the resistance range, it is best to keep the pointer in the middle position of the scale. The purpose of doing this is to minimize measurement errors as much as possible. When measuring, if the numerical range of the measured current and voltage cannot be determined, the conversion switch should be turned to the corresponding large range first, and then gradually reduced to the appropriate range according to the degree of pointer deflection.
Read the table correctly. There are many scales on the dial of a multimeter, which are used for different measuring objects. Therefore, when measuring, it is necessary to read on the corresponding scale, and attention should be paid to the coordination between the scale reading and the measuring range. That is, the "reading" on the scale line of the meter head should not be confused with the "measured value". "Reading" refers to the value directly read from the scale line, while "measured value" represents the measured value represented by the reading, which is often obtained through conversion. Although sometimes the two are numerically the same, in many cases they are different. In addition, when reading, the pointer and its projection on the mirror should overlap to avoid measurement errors.
